Patent Publication Number: US-7592027-B2

Title: Method for the preparation of beverages

Description:
RELATED APPLICATION 
     This application claims priority from U.S. provisional patent application No. 60/462,538, filed Apr. 11, 2003, which is hereby incorporated by reference. 
    
    
     BACKGROUND 
     The present invention relates to a system and method for the preparation of beverages and, in particular, to the use of sealed cartridges which are formed from substantially air- and water-impermeable materials and which contain one or more ingredients for the preparation of beverages. 
     It has previously been proposed to seal beverage preparation ingredients in individual air-impermeable packages for use in beverage machines. For example, cartridges or capsules containing compacted ground coffee are known for use in certain coffee preparation machines which are generally termed “espresso” machines. In the production of coffee using these preparation machines the coffee cartridge is placed in a brewing chamber and hot water is passed though the cartridge at relatively high pressures, thereby extracting the aromatic coffee constituents from the ground coffee to produce the coffee beverage. Typically, such machines operate at a pressure of greater than 6×10 5  Pa. The preparation machines of the type described have to date been relatively expensive since components of the machine, such as the water pumps and seals, must be able to withstand the high pressures. 
     In WO01/58786 there is described a cartridge for the preparation of beverages which operates at a pressure generally in the range 0.7 to 2.0×10 5  Pa. However, the cartridge is designed for use in a beverage preparation machine for the commercial or industrial market and is relatively expensive. 
     It is known to provide dairy-based beverage ingredients in cartridges in the form of a powder or other dehydrated form. However, consumers consistently indicate that the use of such powdered dairy-based products adversely affects the taste, colour and texture of the final beverage. In addition, powdered dairy products cannot be used to produce an authentic looking frothy milk-based foam as desired by consumers for cappuccino-style beverages. A number of beverage preparation machines provide a steam wand or similar for frothing of a quantity of milk. However, the addition of the steam wand increases the cost of the machine and requires a means for generating steam. Operation of the steam wand must be done manually and requires experience to be successful. In addition, since steam is being used there is the potential for the consumer to be burnt by either the steam or hot components of the machine. Further, the consumer must keep a supply of milk available separate from the machine and carry out a further process step of a different type in order to produce a cappuccino style beverage. This increases the complexity and time required to produce such beverages. 
     Hence, there remains a requirement for a system for the preparation of beverages wherein the cartridges and beverage preparation machine of the system are suitable, in particular, for the domestic market in terms of cost, performance and reliability. There is also a need for a beverage preparation machine for such a system which is simple to operate and reliable in operation and can produce a wide range of beverage types. 
     SUMMARY 
     Accordingly, the present invention provides a method of preparing a beverage comprising the steps of:
         a) inserting a first beverage cartridge containing one or more beverage ingredients into a beverage preparation machine;   b) operating said beverage preparation machine to pass an aqueous medium through the first beverage cartridge to dispense a first portion of said beverage into a receptacle;   c) inserting a second beverage cartridge containing one or more beverage ingredients into the beverage preparation machine; and   d) operating the beverage preparation machine to pass an aqueous medium through the second beverage cartridge to dispense a second portion of said beverage into the receptacle;       

     characterised in that one of the first or second beverage cartridges contains a liquid dairy-based ingredient. 
     It will be understood that by the term “cartridge” as used herein is meant any package, container, sachet or receptacle which contains one or more beverage ingredients in the manner described. The cartridge may be rigid, semi-rigid or flexible. 
     The cartridges for use in the present invention may contain one or more beverage ingredients suitable for the formation of a portion of a beverage product. The beverage product portions may be, for example, one of coffee, tea, chocolate or a dairy-based beverage, including milk. The beverage ingredients may be powdered, ground, leaf-based or liquid. The beverage ingredients may be insoluble or soluble. Examples include roast and ground coffee, leaf tea, powdered cocoa solids and soup, liquid milk-based beverages, carbonated drinks and concentrated fruit juices. 
     By using two or more cartridges to prepare a beverage a large variety of beverage can be produced by the same beverage preparation machine. In addition, each cartridge can be optimised for dispensing particular beverage ingredients. In particular, the ability to dispense liquid dairy-based ingredients allows for the formation of beverages having an authentic look, taste and mouth feel which have previously only been possible using non-cartridge based systems such as the use of a separate steam wand to froth bulk quantities of milk. The present method provides a reliable and easy to operate system for forming such beverages. 
     Preferably, one of the first or second beverage cartridges contains an ingredient for forming a brewed portion of a beverage. 
     Preferably, the method further comprises the step of removing the first beverage cartridge before inserting the second beverage cartridge. 
     In one embodiment, the beverage ingredient in the first or second beverage cartridge is roast and ground coffee. In another embodiment, the beverage ingredient in the first or second beverage cartridge is leaf-based tea. In another, the beverage ingredient in the first or second beverage cartridge is a liquid coffee ingredient. 
     Preferably, the liquid beverage ingredient is a concentrated dairy-based product. Advantageously, the concentrated dairy-based product is concentrated liquid milk. Preferably, the concentrated liquid milk contains between 25 and 40% total solids. More preferably, the concentrated liquid milk contains 30% total solids. In addition, preferably, the concentrated liquid milk contains between 0.1 and 12% fat. 
     Preferably, the method further comprises the step of foaming the one or more liquid dairy-based ingredients during dispensation. 
     The present invention also provides a beverage preparation system comprising a beverage preparation machine having means for receiving a range of beverage cartridges and means for passing an aqueous medium through said beverage cartridges, a first beverage cartridge containing one or more beverage ingredients for preparing a first portion of said beverage, and a second beverage cartridge containing one or more beverage ingredients for preparing a second portion of said beverage, characterised in that one of the first or second beverage cartridges contains a liquid dairy-based ingredient. 
     In the following description the terms “upper” and “lower” and equivalents will be used to describe the relational positioning of features of the invention. The terms “upper” and “lower” and equivalents should be understood to refer to the cartridge (or other components) in its normal orientation for insertion into a beverage preparation machine and subsequent dispensing as shown, for example, in  FIG. 4 . In particular, “upper” and “lower” refer, respectively, to relative positions nearer or further from a top surface  11  of the cartridge. In addition, the terms “inner” and “outer” and equivalents will be used to describe the relational positioning of features of the invention. The terms “inner” and “outer” and equivalents should be understood to refer to relative positions in the cartridge (or other components) being, respectively, nearer or further from a centre or major axis X of the cartridge  1  (or other component). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 
         FIG. 1  is cross-sectional drawing of an outer member of first and second embodiments of cartridge for use with the present invention; 
         FIG. 2  is a cross-sectional drawing of a detail of the outer member of  FIG. 1  showing an inwardly directed cylindrical extension; 
         FIG. 3  is a cross-sectional drawing of a detail of the outer member of  FIG. 1  showing a slot; 
         FIG. 4  is a perspective view from above of the outer member of  FIG. 1 ; 
         FIG. 5  is a perspective view from above of the outer member of  FIG. 1  in an inverted orientation; 
         FIG. 6  is a plan view from above of the outer member of  FIG. 1 ; 
         FIG. 7  is a cross-sectional drawing of an inner member of the first embodiment of cartridge; 
         FIG. 8  is a perspective view from above of the inner member of  FIG. 7 ; 
         FIG. 9  is a perspective view from above of the inner member of  FIG. 7  in an inverted orientation; 
         FIG. 10  is a plan view from above of the inner member of  FIG. 7 ; 
         FIG. 11  is a cross-sectional drawing of the first embodiment of cartridge in an assembled condition; 
         FIG. 12  is a cross-sectional drawing of an inner member of the second embodiment of cartridge; 
         FIG. 13  is a cross-sectional drawing of a detail of the inner member of  FIG. 12  showing an aperture; 
         FIG. 14  is a perspective view from above of the inner member of  FIG. 12 ; 
         FIG. 15  is a perspective view from above of the inner member of  FIG. 12  in an inverted orientation; 
         FIG. 16  is another cross-sectional drawing of the inner member of  FIG. 12 ; 
         FIG. 17  is a cross-sectional drawing of another detail of the inner member of  FIG. 12  showing an air inlet; 
         FIG. 18  is a cross-sectional drawing of the second embodiment of cartridge in an assembled condition; 
         FIG. 19  is cross-sectional drawing of an outer member of third and fourth embodiments of cartridge for use with the present invention; 
         FIG. 20  is a cross-sectional drawing of a detail of the outer member of  FIG. 19  showing an inwardly directed cylindrical extension; 
         FIG. 21  is a plan view from above of the outer member of  FIG. 19 ; 
         FIG. 22  is a perspective view from above of the outer member of  FIG. 19 ; 
         FIG. 23  is a perspective view from above of the outer member of  FIG. 19  in an inverted orientation; 
         FIG. 24  is a cross-sectional drawing of an inner member of the third embodiment of cartridge; 
         FIG. 25  is a plan view from above of the inner member of  FIG. 24 ; 
         FIG. 26  is a cross-sectional drawing of a detail of the inner member of  FIG. 24  showing an in-turned upper rim; 
         FIG. 27  is a perspective view from above of the inner member of  FIG. 24 ; 
         FIG. 28  is a perspective view from above of the inner member of  FIG. 24  in an inverted orientation; 
         FIG. 29  is a cross-sectional drawing of the third embodiment of cartridge in an assembled condition; 
         FIG. 30  is a cross-sectional drawing of an inner member of the fourth embodiment of cartridge; 
         FIG. 31  is a plan view from above of the inner member of  FIG. 30 ; 
         FIG. 32  is a perspective view from above of the inner member of  FIG. 30 ; 
         FIG. 33  is a perspective view from above of the inner member of  FIG. 30  in an inverted orientation; 
         FIG. 34  is a cross-sectional drawing of the fourth embodiment of cartridge in an assembled condition; 
         FIG. 35  is a front perspective view of a beverage preparation machine for use with the present invention; 
         FIG. 36  is a front perspective view of the machine of  FIG. 35  with a cartridge head in an open position; 
         FIG. 37  is a rear perspective view of the machine of  FIG. 35  with some parts omitted for clarity; 
         FIG. 38  is another rear perspective view of the machine of  FIG. 35  with some parts omitted for clarity; 
         FIG. 39  is a perspective view of the cartridge head of the machine of  FIG. 35  with some parts omitted for clarity; 
         FIG. 40  is another perspective view of the cartridge head of the machine of  FIG. 35  with some parts omitted for clarity; 
         FIG. 41  is a cross-sectional view of the cartridge head in a closed position; 
         FIG. 42  is a cross-sectional view of the cartridge head in an open position; 
         FIG. 43  is a schematic layout of the machine of  FIG. 35 ; 
         FIG. 44   a  and  44   b  are schematic layouts of first and second code recognition means for the machine of  FIG. 35 ; 
         FIG. 45  is a plan view of a beverage of the present invention comprising a barcode. 
         FIG. 46   a  is a graph of concentration vs. operating cycle time; 
         FIG. 46   b  is a graph of foamability vs. operating cycle time; and 
         FIG. 46   c  is a graph of temperature vs. operating cycle time. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     As shown in  FIG. 11 , the cartridge  1  for use with the present invention generally comprises an outer member  2 , an inner member  3  and a laminate  5 . The outer member  2 , inner member  3  and laminate  5  are assembled to form the cartridge  1  which has an interior  120  for containing one or more beverage ingredients, an inlet  121 , an outlet  122  and a beverage flow path linking the inlet  121  to the outlet  122  and which passes through the interior  120 . The inlet  121  and outlet  122  are initially sealed by the laminate  5  and are opened in use by piercing or cutting of the laminate  5 . The beverage flow path is defined by spatial inter-relationships between the outer member  2 , inner member  3  and laminate  5  as discussed below. Other components may optionally be included in the cartridge  1 , such as a filter  4 , as will be described further below. 
     A first version of cartridge  1  for use in the present invention is shown in  FIGS. 1 to 11 . The first version of the cartridge  1  is particularly designed for use in dispensing filtered products such as roast and ground coffee or leaf tea. However, this version of the cartridge  1  and the other versions described below may be used with other products such as chocolate, coffee, tea, sweeteners, cordials, flavourings, alcoholic beverages, flavoured milk, fruit juices, squashes, sauces and desserts. 
     As can be seen from  FIG. 5 , the overall shape of the cartridge  1  is generally circular or disc-shaped with the diameter of the cartridge  1  being significantly greater than its height. A major axis X passes through the centre of the outer member as shown in  FIG. 1 . Typically the overall diameter of the outer member  2  is 74. 5 mm ±6 mm and the overall height is 16 mm ±3 mm. Typically the volume of the cartridge  1  when assembled is 30.2 ml ±20%. 
     The outer member 2 generally comprises a bowl-shaped shell  10  having a curved annular wall  13 , a closed top  11  and an open bottom  12 . The diameter of the outer member  2  is smaller at the top  11  compared to the diameter at the bottom  12 , resulting from a flaring of the annular wall  13  as one traverses from the closed top  11  to the open bottom  12 . The annular wall  13  and closed bottom  11  together define a receptacle having an interior  34 . 
     A hollow inwardly directed cylindrical extension  18  is provided in the closed top  11  centred on the major axis X. As more clearly shown in  FIG. 2 , the cylindrical extension  18  comprises a stepped profile having first, second and third portions  19 ,  20  and  21 . The first portion  19  is right circular cylindrical. The second portion  20  is frusto-conical in shape and is inwardly tapered. The third portion  21  is another right circular cylinder and is closed off by a lower face  31 . The diameter of the first, second and third portion  19 ,  20  and  21  incrementally decreases such that the diameter of the cylindrical extension  18  decreases as one traverses from the top  11  to the closed lower face  31  of the cylindrical extension  18 . A generally horizontal shoulder  32  is formed on the cylindrical extension  18  at the junction between the second and third portions  20  and  21 . 
     An outwardly extending shoulder  33  is formed in the outer member  2  towards the bottom  12 . The outwardly extending shoulder  33  forms a secondary wall  15  co-axial with the annular wall  13  so as to define an annular track forming a manifold  16  between the secondary wall  15  and the annular wall  13 . The manifold  16  passes around the circumference of the outer member  2 . A series of slots  17  are provided in the annular wall  13  level with the manifold  16  to provide gas and liquid communication between the manifold  16  and the interior  34  of the outer member  2 . As shown in  FIG. 3 , the slots  17  comprise vertical slits in the annular wall  13 . Between  20  and  40  slots are provided. In the embodiment shown thirty-seven slots  17  are provided generally equi-spaced around the circumference of the manifold  16 . The slots  17  are preferably between 1.4 and 1.8 mm in length. Typically the length of each slot is 1.6 mm representing 10% of the overall height of the outer member  2 . The width of each slot is between 0.25 and 0.35 mm. Typically, the width of each slot is 0.3 mm. The width of the slots  17  is sufficiently narrow to prevent the beverage ingredients passing therethrough into the manifold  16  either during storage or in use. 
     An inlet chamber  26  is formed in the outer member  2  at the periphery of the outer member  2 . A cylindrical wall  27  is provided, as most clearly shown in  FIG. 5 , which defines the inlet chamber  26  within, and partitions the inlet chamber  26  from, the interior  34  of the outer member  2 . The cylindrical wall  27  has a closed upper face  28  which is formed on a plane perpendicular to the major axis X and an open lower end  29  co-planar with the bottom  12  of the outer member  2 . The inlet chamber  26  communicates with the manifold  16  via two slots  30  as shown in  FIG. 1 . Alternatively, between one and four slots may be used to communicate between the manifold  16  and the inlet chamber  26 . 
     A lower end of the outwardly extending shoulder  33  is provided with an outwardly extending flange  35  which extends perpendicularly to the major axis X. Typically the flange  35  has a width of between 2 and 4 mm. A portion of the flange  35  is enlarged to form a handle  24  by which the outer member  2  may be held. The handle  24  is provided with an upturned rim  25  to improve grip. 
     The outer member  2  is formed as a single integral piece from high density polyethylene, polypropylene, polystyrene, polyester, or a laminate of two or more of these materials. A suitable polypropylene is the range of polymers available from DSM UK Limited (Redditch, United Kingdom). The outer member may be opaque, transparent or translucent. The manufacturing process may be injection moulding. 
     The inner member  3  as shown in  FIGS. 7 to 10 , comprises an annular frame  41  and a downwardly extending cylindrical funnel  40 . A major axis X passes through the centre of the inner member  3  as shown in  FIG. 7 . 
     As best shown in  FIG. 8 , the annular frame  41  comprises an outer rim  51  and an inner hub  52  joined by ten equi-spaced radial spokes  53 . The inner hub  52  is integral with and extends from the cylindrical funnel  40 . Filtration apertures  55  are formed in the annular frame  41  between the radial spokes  53 . A filter  4  is disposed on the annular frame  41  so as to cover the filtration apertures  55 . The filter is preferably made from a material with a high wet strength, for example a non-woven fibre material of polyester. Other materials which may be used include a water-impermeable cellulosic material, such as a cellulosic material comprising woven paper fibres. The woven paper fibres may be admixed with fibres of polypropylene, polyvinyl chloride and/or polyethylene. The incorporation of these plastic materials into the cellulosic material renders the cellulosic material heat-sealable. The filter  4  may also be treated or coated with a material which is activated by heat and/or pressure so that it can be sealed to the annular frame  41  in this way. 
     As shown in the cross-sectional profile of  FIG. 7 , the inner hub  52  is located at a lower position than the outer rim  51 , resulting in the annular frame  41  having a sloping lower profile. 
     The upper surface of each spoke  53  is provided with an upstanding web  54  which divides a void space above the annular frame  41  into a plurality of passages  57 . Each passage  57  is bounded on either side by a web  54  and on a lower face by the filter  4 . The passages  57  extend from the outer rim  51  downwardly towards, and open into, the cylindrical funnel  40  at openings  56  defined by the inner extremities of the webs  54 . 
     The cylindrical funnel  40  comprises an outer tube  42  surrounding an inner discharge spout  43 . The outer tube  42  forms the exterior of the cylindrical funnel  40 . The discharge spout  43  is joined to the outer tube  42  at an upper end of the discharge spout  43  by means of an annular flange  47 . The discharge spout  43  comprises an inlet  45  at an upper end which communicates with the openings  56  of the passages  57  and an outlet  44  at a lower end through which the prepared beverage is discharged into a cup or other receptacle. The discharge spout  43  comprises a frusto-conical portion  48  at an upper end and a cylindrical portion  58  at a lower end. The cylindrical portion  58  may have a slight taper such that it narrows towards the outlet  44 . The frusto-conical portion  48  helps to channel beverage from the passages  57  down towards the outlet  44  without inducing turbulence to the beverage. An upper surface of the frusto-conical portion  48  is provided with four support webs  49  equi-spaced around the circumference of the cylindrical funnel  40 . The support webs  49  define channels  50  therebetween. The upper edges of the support webs  49  are level with one another and perpendicular to the major axis X. 
     The inner member  3  may be formed as a single integral piece from polypropylene or a similar material as described above and by injection moulding in the same manner as the outer member  2 . 
     Alternatively, the inner member  3  and/or the outer member  2  may be made from a biodegradable polymer. Examples of suitable materials include degradable polyethylene (for example, SPITEK supplied by Symphony Environmental, Borehamwood, United Kingdom), biodegradable polyester amide (for example, BAK 1095 supplied by Symphony Environmental), poly lactic acids (PLA supplied by Cargil, Minn., USA), starch-based polymers, cellulose derivatives and polypeptides. 
     The laminate  5  is formed from two layers, a first layer of aluminium and a second layer of cast polypropylene. The aluminium layer is between 0.02 and 0.07 mm in thickness. The cast polypropylene layer is between 0.025 and 0.065 mm in thickness. In one embodiment the aluminium layer is 0.06 mm and the polypropylene layer is 0.025 mm thick. This laminate is particularly advantageous as it has a high resistance to curling during assembly. As a result the laminate  5  may be pre-cut to the correct size and shape and subsequently transferred to the assembly station on the production line without undergoing distortion. Consequently, the laminate  5  is particularly well suited to welding. Other laminate materials may be used including PET/Aluminium/PP, PE/EVOH/PP, PET/metallised/PP and Aluminium/PP laminates. Roll laminate stock may be used instead of die cut stock. 
     The cartridge  1  may be closed by a rigid or semi-rigid lid instead of a flexible laminate. 
     Assembly of the cartridge  1  involves the following steps:
         a) the inner member  3  is inserted into the outer member  2 ;   b) the filter  4  is cut to shape and placed onto the inner member  3  so to be received over the cylindrical funnel  40  and come to rest against the annular frame  41 ;   c) the inner member  3 , outer member  2  and filter  4  are joined by ultrasonic welding;   d) the cartridge  1  is filled with one or more beverage ingredients;   e) the laminate  5  is affixed to the outer member  2 .       

     These steps will be discussed in greater detail below. 
     The outer member  2  is orientated with the open bottom  12  directed upwards. The inner member  3  is then inserted into the outer member  2  with the outer rim  51  being received as a loose fit in an axial extension  14  at top  11  of the cartridge  1 . The cylindrical extension  18  of the outer member  2  is at the same time received in the upper portion of the cylindrical funnel  40  of the inner member  3 . The third portion  21  of the cylindrical extension  18  is seated inside the cylindrical funnel  40  with the closed lower face of the cylindrical extension  18  bearing against the support webs  49  of the inner member  3 . The filter  4  is then placed over the inner member  3  such that the filter material contacts the annular rim  51 . An ultrasonic welding process is then used to join the filter  4  to the inner member  3  and at the same time, and in the same process step, the inner member  3  to the outer member  2 . The inner member  3  and filter  4  are welded around the outer rim  51 . The inner member  3  and outer member  2  are joined by means of weld lines around the outer rim  51  and also the upper edges of the webs  54 . 
     As shown most clearly in  FIG. 11 , the outer member  2  and inner member  3  when joined together define a void space  130  in the interior  120  below the annular flange  41  and exterior the cylindrical funnel  40  which forms a filtration chamber. The filtration chamber  130  and passages  57  above the annular frame  41  are separated by the filter paper  4 . 
     The filtration chamber  130  contains the one or more beverage ingredients  200 . The one or more beverage ingredients are packed into the filtration chamber  130 . For a filtered style beverage the ingredient is typically roast and ground coffee or leaf tea. The density of packing of the beverage ingredients in the filtration chamber  130  can be varied as desired. Typically, for a filtered coffee product the filtration chamber contains between 5.0 and 10.2 grams of roast and ground coffee in a filtration bed of thickness of typically 5 to 14 mm. Optionally, the interior  120  may contain one or more bodies, such as spheres, which are freely movable within the interior  120  to aid mixing by inducing turbulence and breaking down deposits of beverage ingredients during discharge of the beverage. 
     The laminate  5  is then affixed to the outer member  2  by forming a weld  126  around the periphery of the laminate  5  to join the laminate  5  to the lower surface of the outwardly extending flange  35 . The weld  126  is extended to seal the laminate  5  against the lower edge of the cylindrical wall  27  of the inlet chamber  26 . Further, a weld  125  is formed between the laminate  5  and the lower edge of the outer tube  42  of the cylindrical funnel  40 . The laminate  5  forms the lower wall of the filtration chamber  130  and also seals the inlet chamber  26  and cylindrical funnel  40 . However, a small gap  123  exists prior to dispensation between the laminate  5  and the lower edge of the discharge spout  43 . A variety of welding methods may be used, such as heat and ultrasonic welding, depending on the material characteristics of the laminate  5 . 
     Advantageously, the inner member  3  spans between the outer member  2  and the laminate  5 . The inner member  3  is formed from a material of relative rigidity, such as polypropylene. As such, the inner member  3  forms a load-bearing member that acts to keep the laminate  5  and outer member  2  spaced apart when the cartridge  1  is compressed. It is preferred that the cartridge  1  is subjected to a compressive load of between 130 and 280N in use. The compressive force acts to prevent the cartridge failing under internal pressurisation and also serves to squeeze the inner member  3  and outer member  2  together. This ensures that the internal dimensions of passageways and apertures in the cartridge  1  are fixed and unable to change during pressurisation of the cartridge  1 . 
     To use the cartridge  1  it is first inserted into a beverage preparation machine (which will be described in further detail below) and the inlet  121  and outlet  122  are opened by piercing members of the beverage preparation machine which perforate and fold back the laminate  5 . An aqueous medium, typically water, under pressure enters the cartridge  1  through the inlet  121  into the inlet chamber  26  at a pressure of between 0.1-2.0 bar. From there the water is directed to flow through the slots  30  and round the manifold  16  and into the filtration chamber  130  of the cartridge  1  through the plurality of slots  17 . The water is forced radially inwardly through the filtration chamber  130  and mixes with the beverage ingredients  200  contained therein. The water is at the same time forced upwardly through the beverage ingredients. The beverage formed by passage of the water through the beverage ingredients passes through the filter  4  and filtration apertures  55  into the passages  57  lying above the annular frame  41 . The sealing of the filter  4  onto the spokes  53  and the welding of the rim  51  with the outer member  2  ensures that there are no short-circuits and all the beverage has to pass through the filter  4 . 
     The beverage then flows downwardly along the radial passages  57  formed between the webs  54  and through the openings  56  and into the cylindrical funnel  40 . The beverage passes along the channels  50  between the support webs  47  and down the discharge spout  43  to the outlet  44  where the beverage is discharged into a receptacle such as a cup. 
     Preferably, the beverage preparation machine comprises an air purge facility, wherein compressed air is forced through the cartridge  1  at the end of the operating cycle to flush out the remaining beverage into the receptacle. 
     A second version of cartridge  1  is shown in  FIGS. 12 to 18 . The second version of the cartridge  1  is particularly designed for use in dispensing espresso-style products such as roast and ground coffee where it is desirable to produce a beverage having a froth of tiny bubbles known as a crema. Many of the features of the second version of the cartridge  1  are the same as in the first version and like numerals have been used to reference like features. In the following description the differences between the first and second versions will be discussed. Common features which function in the same manner will not be discussed in detail. 
     The outer member  2  is of the same construction as in the first version of cartridge  1  and as shown in  FIGS. 1 to 6 . 
     The annular frame  41  of the inner member  3  is the same as in the first version. Also, a filter  4  is disposed on the annular frame  41  so as to cover the filtration apertures  55 . The outer tube  42  of the cylindrical funnel  40  is also as before. However, there are a number of differences in the construction of the inner member  2  of the second version compared to the first version. As shown in  FIG. 16 , the discharge spout  43  is provided with a partition  65  which extends part way up the discharge spout  43  from the outlet  44 . The partition  65  helps to prevent the beverage spraying and/or splashing as it exits the discharge spout  43 . The profile of the discharge spout  43  is also different and comprises a stepped profile with a distinct dog-leg  66  near an upper end of the tube  43 . 
     A rim  67  is provided upstanding from the annular flange  47  joining the outer tube  42  to the discharge spout  43 . The rim  67  surrounds the inlet  45  to the discharge spout  43  and defines an annular channel  69  between the rim  67  and the upper portion of the outer tube  42 . The rim  67  is provided with an inwardly directed shoulder  68 . At one point around the circumference of the rim  67  an aperture  70  is provided in the form of a slot which extends from an upper edge of rim  67  to a point marginally below the level of the shoulder  68  as most clearly shown in  FIGS. 12 and 13 . The slot has a width of 0.64 mm. 
     An air inlet  71  is provided in annular flange  47  circumferentially aligned with the aperture  70  as shown in  FIGS. 16 and 17 . The air inlet  71  comprises an aperture passing through the flange  47  so as to provide communication between a point above the flange  47  and the void space below the flange  47  between the outer tube  42  and discharge spout  43 . Preferably, and as shown, the air inlet  71  comprises an upper frusto-conical portion  73  and a lower cylindrical portion  72 . The air inlet  71  is typically formed by a mould tool such as a pin. The tapered profile of the air inlet  71  allows the mould tool to be more easily removed from the moulded component. The wall of the outer tube  42  in the vicinity of the air inlet  71  is shaped to form a chute  75  leading from the air inlet  71  to the inlet  45  of the discharge spout  43 . As shown in  FIG. 17 , a canted shoulder  74  is formed between the air inlet  71  and the chute  75  to ensure that the jet of beverage issuing from the slot  70  does not immediately foul on the upper surface of the flange  47  in the immediate vicinity of the air inlet  71 . 
     The assembly procedure for the second version of cartridge  1  is similar to the assembly of the first version. However, there are certain differences. As shown in  FIG. 18 , the third portion  21  of the cylindrical extension  18  is seated inside the support rim  67  rather than against support webs. The shoulder  32  of the cylindrical extension  18  between the second portion  20  and third portion  21  bears against the upper edge of the support rim  67  of the inner member  3 . An interface zone  124  is thus formed between the inner member  3  and the outer member  2  comprising a face seal between the cylindrical extension  18  and the support rim  67  which extends around nearly the whole circumference of the cartridge  1 . The seal between the cylindrical extension  18  and the support rim  67  is not fluid-tight though since the slot  70  in the support rim  67  extends through the support rim  67  and downwardly to a point marginally below the shoulder  68 . Consequently the interface fit between the cylindrical extension  18  and the support rim  67  transforms the slot  70  into an aperture  128 , as most clearly shown in  FIG. 18 , providing gas and liquid communication between the annular channel  69  and the discharge spout  43 . The aperture is typically 0.64 mm wide by 0.69 mm long. 
     Operation of the second version of cartridge  1  to dispense a beverage is similar to the operation of the first version but with certain differences. Beverage in the radial passages  57  flows downwardly along the passages  57  formed between the webs  54  and through the openings  56  and into the annular channel  69  of the cylindrical funnel  40 . From the annular channel  69  the beverage is forced under pressure through the aperture  128  by the back pressure of beverage collecting in the filtration chamber  130  and passages  57 . The beverage is thus forced through aperture  128  as a jet and into an expansion chamber formed by the upper end of the discharge spout  43 . As shown in  FIG. 18 , the jet of beverage passes directly over the air inlet  71 . As the beverage enters the discharge spout  43  the pressure of the beverage jet drops. As a result air is entrained into the beverage stream in the form of a multitude of small air bubbles as the air is drawn up through the air inlet  71 . The jet of beverage issuing from the aperture  128  is funnelled downwards to the outlet  44  where the beverage is discharged into a receptacle such as a cup where the air bubbles form the desired crema. Thus, the aperture  128  and the air inlet  71  together form an eductor which acts to entrain air into the beverage. Flow of beverage into the eductor should be kept as smooth as possible to reduce pressure losses. Advantageously, the walls of the eductor should be made concave to reduce losses due to ‘wall effect’ friction. The dimensional tolerance of the aperture  128  is small. Preferably the aperture size is fixed plus or minus 0.02 mm 2 . Hairs, fibrils or other surface irregularities can be provided within or at the exit of the eductor to increase the effective cross-sectional area which has been found to increase the degree of air entrainment. 
     A third version of cartridge  1  is shown in  FIGS. 19 to 29 . The third version of the cartridge  1  is particularly designed for use in dispensing soluble products which may be in powdered, liquid, syrup, gel or similar form. The soluble product is dissolved by or forms a suspension in, an aqueous medium such as water when the aqueous medium is passed, in use, through the cartridge  1 . Examples of beverages include chocolate, coffee, milk, tea, soup or other rehydratable or aqueous-soluble products. Many of the features of the third version of the cartridge  1  are the same as in the previous versions and like numerals have been used to reference like features. In the following description the differences between the third and previous versions will be discussed. Common features which function in the same manner will not be discussed in detail. 
     Compared to the outer member  2  of the previous versions, the hollow inwardly directed cylindrical extension  18  of the outer member  2  of the third version has a larger overall diameter as shown in  FIG. 20 . In particular the diameter of the first portion  19  is typically between 16 and 18 mm compared to 13.2 mm for the outer member  2  of the previous versions. In addition, the first portion  19  is provided with a convex outer surface  19   a , or bulge, as most clearly shown in  FIG. 20 , the function of which will be described below. The diameter of the third portions  21  of the cartridges  1  are however the same resulting in the area of the shoulder  32  being greater in this, the third version of the cartridge  1 . Typically the volume of the cartridge  1  when assembled is 32.5 ml ±20%. 
     The number and positioning of the slots in the lower end of the annular wall  13  is also different. Between 3 and 5 slots are provided. In the embodiment as shown in  FIG. 23 , four slots  36  are provided equi-spaced around the circumference of the manifold  16 . The slots  36  are slightly wider than in the previous versions of the cartridge  1  being between 0.35 and 0.45 mm, preferably 0.4 mm wide. 
     In other respects the outer members  2  of the cartridges  1  are the same. 
     The construction of the cylindrical funnel  40  of the inner member  3  is the same as in the first version of cartridge  1  with an outer tube  42 , discharge spout  45 , annular flange  47  and support webs  49  being provided. The only difference is that the discharge spout  45  is shaped with an upper frusto-conical section  92  and a lower cylindrical section  93 . 
     In contrast to the previous versions and as shown in  FIGS. 24 to 28 , the annular frame  41  is replaced by a skirt portion  80  which surrounds the cylindrical funnel  40  and is joined thereto by means of eight radial struts  87  which adjoin the cylindrical funnel  40  at or near the annular flange  47 . A cylindrical extension  81  of the skirt portion  80  extends upwardly from the struts  87  to define a chamber  90  with an open upper face. An upper rim  91  of the cylindrical extension  81  has an in-turned profile as shown in  FIG. 26 . An annular wall  82  of the skirt portion  80  extends downwardly from the struts  87  to define an annular channel  86  between the skirt portion  80  and the outer tube  42 . 
     The annular wall  82  comprises at a lower end an exterior flange  83  which lies perpendicular to the major axis X. A rim  84  depends downwardly from a lower surface of the flange  83  and contains five apertures  85  which are circumferentially equi-spaced around the rim  84 . Thus, the rim  84  is provided with a castellated lower profile. 
     Apertures  89  are provided between the struts  87  allowing communication between the chamber  90  and the annular channel  86 . 
     The assembly procedure for the third version of cartridge  1  is similar to the assembly of the first version but with certain differences. The outer member  2  and inner member  3  are push-fitted together as shown in  FIG. 29  and retained by means of a snap-fit arrangement rather than welded together. On joining the two members the inwardly directed cylindrical extension  18  is received inside the upper cylindrical extension  81  of the skirt portion  80 . The inner member  3  is retained in the outer member  2  by frictional interengagement of the convex outer surface  19   a  of the first portion  19  of the cylindrical extension  18  with the in-turned rim  91  of the upper cylindrical extension  81 . With the inner member  3  located in the outer member  2  a mixing chamber  134  is defined located exterior to the skirt portion  80 . The mixing chamber  134  contains the beverage ingredients  200  prior to dispensation. It should be noted that the four inlets  36  and the five apertures  85  are staggered circumferentially with respect to one another. The radial location of the two parts relative to each other need not be determined or fixed during assembly since the use of four inlets  36  and five apertures  85  ensures that misalignment occurs between the inlets and apertures whatever the relative rotational positioning of the components. 
     The one or more beverage ingredients are packed into the mixing chamber  134  of the cartridge. The density of packing of the beverage ingredients in the mixing chamber  134  can be varied as desired. 
     The laminate  5  is then affixed to the outer member  2  and inner member  3  in the same manner as described above in the previous versions. 
     In use, water enters the mixing chamber  134  through the four slots  36  in the same manner as previous versions of the cartridge. The water is forced radially inwardly through the mixing chamber and mixes with the beverage ingredients contained therein. The product is dissolved or mixed in the water and forms the beverage in the mixing chamber  134  and is then driven though the apertures  85  into the annular channel  86  by back pressure of beverage and water in the mixing chamber  134 . The circumferential staggering of the four inlet slots  36  and the five apertures  85  ensures that jets of water are not able to pass radially directly from the inlet slots  36  to the apertures  85  without first circulating within the mixing chamber  134 . In this way the degree and consistency of dissolution or mixing of the product is significantly increased. The beverage is forced upwardly in the annular channel  86 , through the apertures  89  between the struts  87  and into the chamber  90 . The beverage passes from chamber  90  through the inlets  45  between the support webs  49  into the discharge spout  43  and towards the outlet  44  where the beverage is discharged into a receptacle such as a cup. The cartridge finds particular application with beverage ingredients in the form of viscous liquids or gels. In one application a liquid chocolate ingredient is contained in the cartridge  1  with a viscosity of between 1700 and 3900 mPa at ambient temperature and between 5000 and 10000 mPa at 0° C. and a refractive solids of 67 Brix ±3. In another application liquid coffee is contained in the cartridge  1  with a viscosity of between 70 and 2000 mPa at ambient and between 80 and 5000 mPa at 0° C. where the coffee has a total solids level of between 40 and 70%. The liquid coffee ingredient may contain between 0.1 and 2.0% by weight sodium bicarbonate, preferably between 0.5 and 1.0% by weight. The sodium bicarbonate acts to maintain the pH level of the coffee at or below 4.8 enabling a shelf-life for coffee-filled cartridges of up to 12 months. 
     A fourth version of cartridge  1  is shown in  FIGS. 30 to 34 . The fourth version of the cartridge  1  is particularly designed for use in dispensing liquid products such as concentrated liquid milk. Many of the features of the fourth version of the cartridge  1  are the same as in the previous versions and like numerals have been used to reference like features. In the following description the differences between the fourth and previous versions will be discussed. Common features which function in the same manner will not be discussed in detail. 
     The outer member  2  is the same as in the third version of cartridge  1  and as shown in  FIGS. 19 to 23 . 
     The cylindrical funnel  40  of the inner member  3  is similar to that shown in the second version of cartridge  1  but with certain differences. As shown in  FIG. 30  the discharge spout  43  is shaped with an upper frusto-conical section  106  and a lower cylindrical section  107 . Three axial ribs  105  are provided on the inner surface of the discharge spout  43  to direct the dispensed beverage downwards towards the outlet  44  and prevent the discharged beverage from spinning within the spout. Consequently, the ribs  105  act as baffles. As in the second version of cartridge  1 , an air inlet  71  is provided through the annular flange  47 . However, the chute  75  beneath the air inlet  71  is more elongated than in the second version. 
     A skirt portion  80  is provided similar to that shown in the third version of the cartridge  1  described above. Between 5 and 12 apertures  85  are provided in the rim  84 . Typically ten apertures are provided rather than the five provided in the third version of cartridge  1 . 
     An annular bowl  100  is provided extending from and integral with the flange  83  of the skirt portion  80 . The annular bowl  100  comprises a flared body  101  with an open upper mouth  104  which is directed upwards. Four feed apertures  103  shown in  FIGS. 30 and 31  are located in the body  101  at or near the lower end of the bowl  100  where it joins the skirt portion  80 . Preferably, the feed apertures are equi-spaced around the circumference of the bowl  100 . 
     The laminate  5  is of the type described above in the previous embodiments. 
     The assembly procedure for the fourth version of cartridge  1  is the same as that for the third version. 
     Operation of the fourth version of cartridge is similar to that of the third version. The water enters the cartridge  1  and the mixing chamber  134  in the same manner as before. There the water mixes with and dilutes the liquid product which is then forced out below the bowl  100  and through the apertures  85  towards the outlet  44  as described above. The proportion of the liquid product initially contained within the annular bowl  100  as shown in  FIG. 34  is not subject to immediate dilution by the water entering the mixing chamber  134 . Rather, the diluted liquid product in the lower part of the mixing chamber  134  will tend to exit through apertures  85  rather than be forced up and into the annular bowl  100  through upper mouth  104 . Consequently, the liquid product in the annular bowl  100  will remain relatively concentrated during the initial stages of the operating cycle compared to the product in the lower part of the mixing chamber  134 . The liquid product in the annular bowl  100  drips through the feed apertures  103  under gravity into the stream of product exiting the mixing chamber  134  through the apertures  85  and below the bowl  100 . The annular bowl  100  acts to even out the concentration of the diluted liquid product entering the cylindrical funnel  40  by holding back a proportion of the concentrated liquid product and releasing it into the exiting liquid stream flow path steadily throughout the operating cycle as illustrated in  FIG. 46   a  where the concentration of the milk measured as a percentage of the total solids present is shown during an operating cycle of approximately 15 seconds. Line a illustrates the concentration profile with the bowl  100  whilst line b illustrates a cartridge without the bowl  100 . As can be seen the concentration profile with the cup  100  is more even during the operating cycle and there is no immediate large drop in concentration as occurs without the bowl  100 . The initial concentration of the milk is typically 30-35% SS and at the end of the cycle 10% SS. This results in a dilution ratio of around 3 to 1, although dilution ratios of between 1 to 1 and 6 to 1 are possible with the present invention. For other liquid beverage ingredients the concentrations may vary. For example for liquid chocolate the initial concentration is approximately 67% SS and at the end of the cycle 12-15% SS. This results in a dilution ratio (ratio of aqueous medium to beverage ingredient in dispensed beverage) of around 5 to 1, although dilution ratios of between 2 to 1 and 10 to 1 are possible with the present invention. For liquid coffee the initial concentration is between 40-67% and the concentration at the end of dispense 1-2% SS. This results in a dilution ratio of between 20 to 1 and 70 to 1, although dilution ratios of between 10 to 1 and 100 to 1 are possible with the present invention. 
     From the annular channel  86  the beverage is forced under pressure through the aperture  128  by the back pressure of beverage collecting in the filtration chamber  134  and chamber  90 . The beverage is thus forced through aperture  128  as a jet and into an expansion chamber formed by the upper end of the discharge spout  43 . As shown in  FIG. 34 , the jet of beverage passes directly over the air inlet  71 . As the beverage enters the discharge spout  43  the pressure of the beverage jet drops. As a result air is entrained into the beverage stream in the form of a multitude of small air bubbles as the air is drawn up through the air inlet  71 . The jet of beverage issuing from the aperture  128  is funnelled downwards to the outlet  44  where the beverage is discharged into a receptacle such as a cup where the air bubbles form the desired frothy appearance. 
     Advantageously, the inner member  3 , outer member  2 , laminate  5  and filter  4  can all be readily sterilised due to the components being separable and not individually comprising tortuous passageways or narrow crevices. Rather, it is only after conjoining the components, after sterilisation, that the necessary passageways are formed. This is particularly important where the beverage ingredient is a dairy-based product such as liquid milk concentrate. 
     The fourth embodiment of beverage cartridge is particularly advantageous for dispensing a concentrated dairy-based liquid product such as liquid milk. Previously, powdered milk products have been provided in the form of sachets for adding to a pre-prepared beverage. However, for a cappuccino-style beverage it is necessary to foam the milk. This has been achieved previously by passing steam through a liquid milk product. However this necessitates the provision of a steam supply which increases the cost and complexity of the machine used to dispense the beverage. The use of steam also increases the risk of injury during operation of the cartridge. Accordingly the present invention provides for a beverage cartridge having a concentrated dairy-based liquid product therein. It has been found that by concentrating the milk product a greater amount of foam can be produced for a particular volume of milk when compared to fresh or UHT milk. This reduces the size required for the milk cartridge. Fresh semi-skimmed milk contains approximately 1.6% fat and 10% total solids. The concentrated liquid milk preparations of the present invention contain between 0.1 and 12% fat and 25 to 40% total solids. In a typical example, the preparation contains 4% fat and 30% total solids. The concentrated milk preparations are suitable for foaming using a low pressure preparation machine as will be described below. In particular, foaming of the milk is achieved at pressures below 2 bar, preferably approximately 1.5 bar using the cartridge of the fourth embodiment described above. 
     The foaming of the concentrated milk is particularly advantageous for beverages such as cappuccinos and milk shakes. Preferably the passing of the milk through the aperture  128  and over the air inlet  71  and the optional use of the bowl  100  enables foaming levels of greater than 40%, preferably greater than 70% for milk. For liquid chocolate foaming levels of greater than 70% are possible. For liquid coffee foaming levels of greater than 70% are possible. The foamability level is measured as the ratio of the volume of the foam produced to the volume of liquid beverage ingredient dispensed. For example, where 138.3 ml of beverage is dispensed, of which 58.3 ml is foam the foamability is measured as [58.3/(138.3-58.3)]*100=72.9%. The foamability of the milk (and other liquid ingredients) is enhanced by the provision of the bowl  100  as can be seen in  FIG. 46   b . The foamability of the milk dispensed with the bowl  100  present (line a) is greater than that of milk dispensed without the bowl present (line b). This is because the foamability of the milk is positively correlated to the concentration of the milk and as shown in  FIG. 46   a  the bowl  100  maintains a higher concentration of the milk a larger part of the operating cycle. It is also known that foamability of the milk is positively correlated to temperature of the aqueous medium as shown in  FIG. 46   c . Thus the bowl  100  is advantageous since more of the milk remains in the cartridge until near the end of the operating cycle when the aqueous medium is at its hottest. This again improves foamability. 
     The cartridge of the fourth embodiment is also advantageous in dispensing liquid coffee products. 
     It has been found that the embodiments of beverage cartridge of the present invention advantageously provide an improved consistency of the dispensed beverage when compared to prior art cartridges. Reference is made to Table 1 below which shows the results of brew yields for twenty samples each of cartridges A and B containing roast and ground coffee. Cartridge A is a beverage cartridge according to the first embodiment of the present invention. Cartridge B is a prior art beverage cartridge as described in the applicant&#39;s document WO01/58786. The refractive index of the brewed beverage is measured in Brix units and converted to a percentage of soluble solids (% SS) using standard tables and formulae. In the examples below:
 
% SS=0.7774*(Brix value)+0.0569.
 
% Yield=(% SS *Brew Volume (g))/(100 *Coffee Weight (g))
 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                   
                 Coffee 
                   
                   
                   
               
               
                 Sample 
                 Brew Volume (g) 
                 Weight (g) 
                 Brix 
                 % SS (*) 
                 % Yield 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 CARTRIDGE A 
               
            
           
           
               
               
               
               
               
               
            
               
                 1 
                 105.6 
                 6.5 
                 1.58 
                 1.29 
                 20.88 
               
               
                 2 
                 104.24 
                 6.5 
                 1.64 
                 1.33 
                 21.36 
               
               
                 3 
                 100.95 
                 6.5 
                 1.67 
                 1.36 
                 21.05 
               
               
                 4 
                 102.23 
                 6.5 
                 1.71 
                 1.39 
                 21.80 
               
               
                 5 
                 100.49 
                 6.5 
                 1.73 
                 1.40 
                 21.67 
               
               
                 6 
                 107.54 
                 6.5 
                 1.59 
                 1.29 
                 21.39 
               
               
                 7 
                 102.70 
                 6.5 
                 1.67 
                 1.36 
                 21.41 
               
               
                 8 
                 97.77 
                 6.5 
                 1.86 
                 1.50 
                 22.61 
               
               
                 9 
                 97.82 
                 6.5 
                 1.7 
                 1.38 
                 20.75 
               
               
                 10 
                 97.83 
                 6.5 
                 1.67 
                 1.36 
                 20.40 
               
               
                 11 
                 97.6 
                 6.5 
                 1.78 
                 1.44 
                 21.63 
               
               
                 12 
                 106.64 
                 6.5 
                 1.61 
                 1.31 
                 21.47 
               
               
                 13 
                 99.26 
                 6.5 
                 1.54 
                 1.25 
                 19.15 
               
               
                 14 
                 97.29 
                 6.5 
                 1.59 
                 1.29 
                 19.35 
               
               
                 15 
                 101.54 
                 6.5 
                 1.51 
                 1.23 
                 19.23 
               
               
                 16 
                 104.23 
                 6.5 
                 1.61 
                 1.31 
                 20.98 
               
               
                 17 
                 97.5 
                 6.5 
                 1.73 
                 1.40 
                 21.03 
               
               
                 18 
                 100.83 
                 6.5 
                 1.68 
                 1.36 
                 21.14 
               
               
                 19 
                 101.67 
                 6.5 
                 1.67 
                 1.36 
                 21.20 
               
               
                 20 
                 101.32 
                 6.5 
                 1.68 
                 1.36 
                 21.24 
               
               
                   
                   
                   
                   
                 AVERAGE 
                 20.99 
               
            
           
           
               
            
               
                 CARTRIDGE B 
               
            
           
           
               
               
               
               
               
               
            
               
                 1 
                 100.65 
                 6.5 
                 1.87 
                 1.511 
                 23.39 
               
               
                 2 
                 95.85 
                 6.5 
                 1.86 
                 1.503 
                 22.16 
               
               
                 3 
                 98.4 
                 6.5 
                 1.8 
                 1.456 
                 22.04 
               
               
                 4 
                 92.43 
                 6.5 
                 2.3 
                 1.845 
                 26.23 
               
               
                 5 
                 100.26 
                 6.5 
                 1.72 
                 1.394 
                 21.50 
               
               
                 6 
                 98.05 
                 6.5 
                 2.05 
                 1.651 
                 24.90 
               
               
                 7 
                 99.49 
                 6.5 
                 1.96 
                 1.581 
                 24.19 
               
               
                 8 
                 95.62 
                 6.5 
                 2.3 
                 1.845 
                 27.14 
               
               
                 9 
                 94.28 
                 6.5 
                 2.17 
                 1.744 
                 25.29 
               
               
                 10 
                 96.13 
                 6.5 
                 1.72 
                 1.394 
                 20.62 
               
               
                 11 
                 96.86 
                 6.5 
                 1.81 
                 1.464 
                 21.82 
               
               
                 12 
                 94.03 
                 6.5 
                 2.2 
                 1.767 
                 25.56 
               
               
                 13 
                 96.28 
                 6.5 
                 1.78 
                 1.441 
                 21.34 
               
               
                 14 
                 95.85 
                 6.5 
                 1.95 
                 1.573 
                 23.19 
               
               
                 15 
                 95.36 
                 6.5 
                 1.88 
                 1.518 
                 22.28 
               
               
                 16 
                 92.73 
                 6.5 
                 1.89 
                 1.526 
                 21.77 
               
               
                 17 
                 88 
                 6.5 
                 1.59 
                 1.293 
                 17.50 
               
               
                 18 
                 93.5 
                 6.5 
                 2.08 
                 1.674 
                 24.08 
               
               
                 19 
                 100.88 
                 6.5 
                 1.75 
                 1.417 
                 22.00 
               
               
                 20 
                 84.77 
                 6.5 
                 2.37 
                 1.899 
                 24.77 
               
               
                   
                   
                   
                   
                 AVERAGE 
                 23.09 
               
               
                   
               
            
           
         
       
     
     Performing a t-test statistical analysis on the above data gives the following results: 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 t-Test: Two-Sample Assuming Equal Variances 
               
            
           
           
               
               
               
            
               
                   
                 % Yield (Cartridge A) 
                 % Yield (Cartridge B) 
               
               
                   
                   
               
            
           
           
               
               
               
            
               
                 Mean 
                 20.99 
                 23.09 
               
               
                 Variance 
                 0.77 
                 5.04 
               
               
                 Observations 
                 20 
                 20 
               
               
                 Pooled Variance 
                 2.90 
               
               
                 Hypothesized Mean 
                 0 
               
               
                 Difference 
               
               
                 df 
                 38 
               
               
                 t Stat 
                 −3.90 
               
               
                 P(T &lt;= t) one-tail 
                 0.000188 
               
               
                 t Critical one-tail 
                 1.686 
               
               
                 P(T &lt;= t) two-tail 
                 0.000376 
               
               
                 t Critical two-tail 
                 2.0244 
               
               
                 Standard Deviation 
                 0.876 
                 2.245 
               
               
                   
               
            
           
         
       
     
     The analysis shows that the consistency of % yield, which equates to brew strength, for the cartridges of the present invention is significantly better (at a 95% confidence level) than the prior art cartridges, with a standard deviation of 0.88% compared to 2.24%. This means that beverages dispensed with the cartridges of the present invention have a more repeatable and uniform strength. This is preferred by consumers who like their drinks to taste the same time after time and do not want arbitrary changes in drink strength. 
     The beverage cartridges as described above can be used in combination to produce a wide variety of beverages. For example, a first version of cartridge as described above can be used to dispense a brewed portion of filtered roast and ground coffee followed by a fourth version of cartridge as described above to dispense a frothed milk portion into the beverage. The order of dispense can be reversed if desired with the milk being dispensed first followed by the coffee. More than two cartridges can be used to form the finished beverage. 
     The materials of the cartridges described above may be provided with a barrier coating to improve their resistance to oxygen and/or moisture and/or other contaminant ingress. The barrier coating may also improve the resistance to leakage of the beverage ingredients from within the cartridges and/or reduce the degree of leaching of extractibles from the cartridge materials which might adversely affect the beverage ingredients. The barrier coating may be of a material selected from the group of PET, Polyamide, EVOH, PVDC or a metallised material. The barrier coating may be applied by a number of mechanisms including but not limited to vapour deposition, vacuum deposition, plasma coating, co-extrusion, in-mould labelling and two/multi-stage moulding. 
     A beverage preparation machine  201  for use with the present invention for use with the above described beverage cartridges is shown in  FIGS. 35 to 45 . The beverage preparation machine  201  generally comprises a housing  210  containing a water tank  220 , a water heater  225 , a water pump  230 , an air compressor  235 , a control processor, a user interface  240  and a cartridge head  250 . The cartridge head  250  in turn generally comprises a cartridge holder  251  for holding, in use, the beverage cartridge  1 , cartridge recognition means  252  and inlet and outlet piercers  253 ,  254  for forming, in use, the inlet  121  and the outlet  122  in the beverage cartridge  1 . 
     The housing  210  contains and holds in position the other components of the machine  201 . The housing  210  preferably made in whole or in part from a robust plastics material such as ABS. Alternatively, the housing  210  can be made in whole or in part from a metallic material such as stainless steel or aluminium. The housing  210  is preferably comprises a clam-shell design having a front half  211  and a rear half  212  which allow access during assembly for fitting of the machine  201  components and can afterwards be joined together to define an interior  213  of the housing  210 . The rear half  212  provides a recess  214  for the attachment of the water tank  220 . The housing  210  is formed with means, such as detents, abutments, bosses and threaded portions, for retaining the components of the machine  201  in position without the need for a separate chassis. This reduces the overall cost and weight of the machine  201 . A base  215  of the housing  210  is preferably provided with feet for standing the machine thereon in a stable manner. Alternatively, the base  215  itself may have a shape forming a stable support. 
     The front half  211  of the housing  210  comprises a dispense station  270  where dispensation of the beverage takes place. The dispense station  270  comprises a receptacle stand  271  having a hollow interior forming a drip tray  272 . An upper surface  273  of the receptacle stand is provided with a grill  274  on which the receptacle is positioned. The drip tray  272  is removable from the housing  210  to ease emptying of the collected water. A recess  275  is formed in the front half of the housing  210  above the receptacle stand  271  to accommodate the dimensions of the receptacle. 
     The cartridge head  250  is located towards the top of the housing  210  above the receptacle stand as shown in  FIGS. 35 and 36 . Preferably, the height of the grill  274  relative to the cartridge head  250  can be adjusted to accommodate different sizes of receptacle. It is preferred that the receptacle is as close to the cartridge head  250  as possible, whilst still allowing the receptacle to be inserted and withdrawn from the dispense station  270 , so as to minimise the height that the dispensed beverage has to descend before contacting the receptacle. This acts to minimise spraying and splashing of the beverage and minimise loss of entrained air bubbles where these are present. Preferably receptacles of between 70 mm and 110 mm in height can be inserted between the grill  274  and cartridge head  250 . 
     The machine user interface  240  is located on the front of the housing  210  and comprises a start/stop button  241 , and a plurality of status indicators  243 - 246 . 
     The status indicators  243 - 246  preferably include a light emitting diode (LED)  243  to indicate readiness of the machine  201 , a LED  244  to indicate if an error has occurred in the machine  201  operation, and one or more LEDs  245 - 256  to indicate whether the machine  201  is operating in manual or automatic modes. The LEDs  243 - 246  may be controlled to illuminate at a constant intensity, to flash intermittently, or both depending on the status of the machine  201 . The LEDs  243 - 246  may have a variety of colours including green, red and yellow. 
     The start/stop button  241  controls commencement of the operating cycle and is a manually operated push-button, switch or similar. 
     A volume adjustment control may be provided to allow a user of the machine  201  to manually adjust the volume of the delivered beverage without altering the other operating characteristics. Preferably the volume adjustment control allows an adjustment in volume of plus or minus 20%. The volume adjustment control may be a rotary knob, a linear slider, a digital readout with increment and decrement buttons, or similar. More typically, volume is controlled by a user operating the start/stop button  241 . 
     A manual power switch (not shown) may be provided on the machine  201 . Alternatively, power supply can be controlled simply by insertion or removal or the power supply plug from the mains power supply. 
     The water tank  220  is located to the rear of the housing  210  and is connected to the rear half  212  of the housing  210 . The water tank  220  comprises a generally cylindrical body  221  which may be right circular or a frustum as desired for aesthetic reasons. The tank comprises an inlet for filling the tank with water which is closed off in use by a manually removable lid  222 . An outlet is provided towards a lower end of the tank which communicates with the water pump  230 . The water tank  220  may be made from a transparent or translucent material to allow a consumer to view the quantity of water remaining in the tank. Alternatively, the water tank  220  may be made from an opaque material but have provided a viewing window therein. In addition, or in place of the above, the water tank  220  may be provided with a low level sensor which prevents operation of the water pump  230  and optionally triggers a warning indicator, such as an LED, when the water level in the tank descends to a preselected level. The water tank  220  preferably has an internal capacity of approximately 1.5 liters. 
     The water pump  230  is operatively connected between the water tank  220  and the water heater  225  as shown schematically in  FIG. 43  and is controlled by the control processor. The pump provides a maximum flow rate of 900 ml/min of water at a maximum pressure of 2.5 bar. Preferably, in normal use, the pressure will be limited to 2 bar. The flow rate of water through the machine  201  can be controlled by the control processor to be a percentage of the maximum flow rate of the pump by cycle chopping the electrical supply to the pump. Preferably the pump can be driven at any of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100% of the maximum rated flow rate. The accuracy of the volume of water pumped is preferably + or − 5% leading to a + or − 5% accuracy in the final volume of the dispensed beverage. A suitable pump is the Evolution EP8 pump produced by Ulka S.r.l. (Pavia, Italy). A volumetric flow sensor (not shown) is preferably provided in the flow line either upstream or downstream of the water pump  230 . Preferably, the volumetric flow sensor is a rotary sensor. 
     The water heater  225  is located in the interior of the housing  210 . The heater  225  has a power rating of 1550 W and is able to heat water received from the water pump  230  from a starting temperature of approximately 20° C. to an operating temperature of around 85° C. in under 1 minute. Preferably the dwell time between the end of one operating cycle and the heater  225  being able to commence a subsequent operating cycle is less than 10 seconds. The heater maintains the selected temperature to within + or −2° C. during the operating cycle. As discussed below, the water for the operating cycle may be delivered to the cartridge head  250  at 8° C. or 93° C. The heater  225  is able to quickly adjust the delivery temperature to either 83° C. or 93° C. from a nominal water temperature of 85° C. The heater  225  comprises an over-temperature cut-off which shuts off the heater if the temperature exceeds 98° C. Water output from the heater  225  is fed to the cartridge head  250  and cartridge  1  by means of a three-way valve. If the pressure of the water flow is acceptable the water is passed to the cartridge  1 . If the pressure is below or above predetermined limits then the water is diverted by means of the three-way valve into the drip tray recovery receptacle  270 . 
     The air compressor  235  is operatively connected to the cartridge head  250  by means of a one-way valve and controlled by the control processor. The air compressor  235  provides a maximum flow rate of air of 500 ml/min at 1.0 bar. In use a working volume of 35 ml is pressurised to 2.0 bar. Preferably, the air compressor  235  can produce two flow rates: a fast (or maximum) flow rate and a slow flow rate. 
     The control processor of the beverage preparation machine  201  comprises a processing module and a memory. The control processor is operatively connected to, and controls operation of, the water heater  225 , water pump  230 , air compressor  235  and user interface  240 . 
     The memory of the control processor includes one or more variables for one or more operational parameters for the beverage preparation machine  201 . In the illustrated embodiment the operational parameters are the temperature of the water passed through the beverage cartridge  1  during the operating stage, the speed of charging the beverage cartridge  1 , the presence or otherwise of a soak step, the total dispensed volume of the beverage, the flow rate of the water during the discharge stage, and the flow rate and period of the purge stage. 
     The variables for the operational parameters are stored in the memory. The cartridge  1  comprises a code provided on or in the cartridge  1  representing the operational parameters required for optimal dispensation of the beverage in that cartridge  1 . The code is in binary format and comprises a plurality of data bits corresponding to the variables stored in the control processor memory. Table 3 illustrates how 13 bits of data can be used to represent the necessary variables for the operational parameters described above. 
     
       
         
           
               
               
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 Bit 
                 Parameter 
                 Description 
               
               
                   
               
             
            
               
                 0 &amp; 1 
                 Water temperature 
                 00 = cold 
               
               
                   
                   
                 01 = warm 
               
               
                   
                   
                 10 = 83° C. 
               
               
                   
                   
                 11 = 93° C. 
               
               
                 2 &amp; 3 
                 Cartridge charge 
                 00 = fast charge with soak 
               
               
                   
                   
                 01 = fast charge without soak 
               
               
                   
                   
                 10 = slow charge with soak 
               
               
                   
                   
                 11 = slow charge without soak 
               
               
                 4, 5, 6 &amp; 7 
                 Beverage volume 
                 0000 = 50 ml 
               
               
                   
                   
                 0001 = 60 ml 
               
               
                   
                   
                 0010 = 70 ml 
               
               
                   
                   
                 0011 = 80 ml 
               
               
                   
                   
                 0100 = 90 ml 
               
               
                   
                   
                 0101 = 100 ml 
               
               
                   
                   
                 0110 = 110 ml 
               
               
                   
                   
                 0111 = 130 ml 
               
               
                   
                   
                 1000 = 150 ml 
               
               
                   
                   
                 1001 = 170 ml 
               
               
                   
                   
                 1010 = 190 ml 
               
               
                   
                   
                 1011 = 210 ml 
               
               
                   
                   
                 1100 = 230 ml 
               
               
                   
                   
                 1101 = 250 ml 
               
               
                   
                   
                 1110 = 275 ml 
               
               
                   
                   
                 1111 = 300 ml 
               
               
                 8, 9 &amp; 10 
                 Flow rate 
                 000 = 30% 
               
               
                   
                   
                 001 = 40% 
               
               
                   
                   
                 010 = 50% 
               
               
                   
                   
                 011 = 60% 
               
               
                   
                   
                 100 = 70% 
               
               
                   
                   
                 101 = 80% 
               
               
                   
                   
                 110 = 90% 
               
               
                   
                   
                 111 = 100% 
               
               
                 11 &amp; 12 
                 Purge 
                 00 = slow flow/short period 
               
               
                   
                   
                 01 = slow flow/long period 
               
               
                   
                   
                 10 = fast flow/short period 
               
               
                   
                   
                 11 = fast flow/long period 
               
               
                   
               
            
           
         
       
     
     The code on or in the cartridge  1  will normally comprises one or more extra data bits for error checking. In one example a 16 bit code is provided. For example, using the variables listed in Table 3, a cartridge  1  bearing the code “1000100011110” would have the following operational parameters: 
     
       
         
           
               
               
             
               
                   
               
             
            
               
                 10 
                 Water temperature of 83° C. 
               
               
                 00 
                 Fast charge with soak 
               
               
                 1000 
                 Dispensed drink volume of 150 ml 
               
               
                 111 
                 Flow rate equals 100% 
               
               
                 10 
                 Fast air flow purge/short period. 
               
               
                   
               
            
           
         
       
     
     Thus, unlike in previous beverage preparation machines, the memory of the control processor does not store operational instructions for beverage cartridges based on the cartridge type, i.e. instructions for a coffee cartridge, instructions for a chocolate cartridge, instructions for a tea cartridge etc. Instead the memory of the control processor stores variables for adjusting the individual operational parameters of the operating cycle. This has a number of advantages. Firstly, a greater degree of control of the dispensation cycle can be exercised. For example, slightly different operational parameters can be used for different grades or blends of coffee rather than using the same parameters for all types of coffee. Prior coding solutions relying on storing instructions by cartridge type rather than by individual parameters are unsuited to such subtle differences in operating cycles for similar beverage types because they quickly consume the available storage space in the coding medium and control processor. Secondly, the coding method of the present invention allows for new beverage cartridge types to be used in pre-existing beverage preparation machines even where the operational parameters for the operating cycle for the new beverage cartridge  1  are only decided upon after sale of the beverage preparation machine  201 . This is because the control processor of the beverage preparation machine  201  does not need to recognise that the beverage is of a new type. Rather the operational parameters of the operating cycle are set without direct reference to the beverage type. Hence the coding method of the present invention provides excellent backward compatibility of the beverage preparation machines for new beverage types. In contrast, with prior machines, the manufacturer is restricted to dispensing a new beverage type using one of the pre-existing dispensation cycles as determined by the in-market machines. 
     The cartridge head  250  is shown in  FIGS. 39 to 42 . The cartridge holder  251  of the cartridge head  250  comprises a fixed lower part  255 , a rotatable upper part  256  and a pivotable cartridge mount  257  positioned in between the fixed lower part  255  and the rotatable upper part  256 . The upper part  256 , lower part  255  and cartridge mount  257  are rotated about a common hinge axis  258 .  FIGS. 39 to 42  show the cartridge holder  251  with some components of the machine  201  omitted for clarity. 
     The rotatable upper part  256  and pivotable cartridge mount  257  are moved relative to the fixed lower part  255  by means of a clamping mechanism  280 . The clamping mechanism  280  comprises a clamping lever having first and second members or parts  281  and  282 . The first part  281  of the clamping lever comprises a U-shaped arm which is pivotably mounted to the upper part  256  at two first pivot points  283 , one on each side of the cartridge holder  251 . 
     The second part of the clamping lever comprises two over-centre arms  282 , one on each side of the cartridge holder  251  which are each pivotably mounted to the upper part  256  at a second pivot point  285  located on the hinge axis  258  coupling the upper part  256  to the fixed lower part  255 . Each over-centre arm  282  is a reciprocal member comprising a cylinder  282   a , a stem  282   b  and a resilient sleeve  282   c . The cylinder  282   a  has an internal bore and is rotatably mounted at one end at the hinge axis  258 . A first end of the stem  282   b  is slidingly received in the bore of the cylinder  282   a . The opposite end of the stem  282   b  is rotatably mounted to the U-shaped arm  281  at a third pivot point  286 . The third pivot points  286  are unconnected to, and freely moveable relative to, the upper part  256  and lower part  255 . The resilient sleeve  282   c  is mounted externally on the stem  282   b  and extends, in use, between abutment surfaces on the cylinder  282   a  and stem  282   b . The resilient sleeve  282   c  accommodates shortening of the over-centre arm  282  but biases the over-centre arm  282  into an extended configuration. Movement of the third pivot points  286  towards and away from the hinge axis  258  is thus possible by relative movement of the stems  282   b  in the cylinders  282   a . The resilient sleeves  282   c  are preferably formed from silicone. 
     The U-shaped arm  281  extends around the front of the cartridge holder  251  and comprises two downwardly dependent hook members  287 , one on each side of the cartridge holder  251 , each comprising a cam surface  288  facing the hinge axis  258 . The fixed lower part  255  of the cartridge holder  251  is provided with two bosses  259 , or detents, located one on each side of the lower part  255  at or near a front edge  260  thereof aligned generally with the hook members  287 . 
     As shown in  FIG. 39 , the U-shaped arm  281  may be formed from a one piece plastics moulding comprising an ergonomic hand grip and the hook members  287  integral to the arm. 
     The cartridge mount  257  is rotatably mounted between the upper and lower parts  255 ,  256  of the cartridge holder  251 . The mount  257  is provided with a substantially circular recess  290  which receives in use the beverage cartridge  1 . The recess  290  includes an irregularity  291  for accommodating the handle portion  24  of the beverage cartridge  1  which also acts to prevent rotation of the beverage cartridge  1  in the cartridge holder  251 . The cartridge mount  257  is sprung relative to the fixed lower part  255  such that in the open position, as shown in  FIG. 41 , the cartridge mount  257  is biased out of contact with the fixed lower part  255  so that the cartridge mount  257  is moved out of contact with the outlet and inlet piercer members  254 ,  253 . The cartridge mount  257  is provided with an aperture  292  for receiving therethrough the inlet and outlet piercers  253 ,  254  and a head  300  of the cartridge recognition means  252  when the cartridge mount  257  is moved into the closed position. 
     The upper part  255  comprises a generally circular body  310  housing a circular viewing window  312  through which a consumer can view the beverage cartridge  1  during an operating cycle and also visually confirm whether a cartridge  1  is loaded in the machine  201 . The viewing window  312  is cup-shaped having a downwardly directed rim  311  which engages and grips the flange  35  of the beverage cartridge  1  against the lower part  256  when the cartridge holder  251  is closed. At the same time the window  312  contacts the closed top  11  of the cartridge  1 . A wave spring (not shown) is positioned between the viewing window  312  and the circular body  310  to enable the viewing window  312  to move axially relative to the circular body  310  by a small degree. The pressure exerted by the rim  311  on the flange  35  and by the window  312  on the closed top  11  ensures a fluid tight seal between the cartridge  1  and the cartridge holder  251 . 
     The lower part  255  comprises the inlet and outlet piercers  253 ,  254  and the head  300  of the cartridge recognition means  252 . The inlet piercer  253  comprises a hollow needle-like tube  260  having a sharpened end  261  for perforating the laminate  5  of the beverage cartridge  1  in use. The inlet piercer  253  is in fluid communication with a water conduit  262  as shown in  FIG. 42  which passes through the lower part  255  and is connected to an outlet conduit  263  of the water heater  225 . The outlet piercer  254  is similar in type to the outlet piercer described in the applicant&#39;s European patents EP 0 389 141 and EP 0 334 572 and comprises an open ended cylinder  264  of circular or D-shaped cross-section having dimensions larger than the discharge spout  43 . An arcuate portion  265  of the upper end of the outlet piercer  254  is serrated to pierce and eventually cut the laminate of the beverage cartridge  1 . The remainder of the upper end is cut back longitudinally of the cylinder at least to the base of the teeth  266  of the serrated portion to fold or pull the cut laminate  5  away from the outlet aperture before the beverage is dispensed therethrough. The outlet piercer  254  pierces the laminate  5  externally of the discharge spout  43  and when the cartridge mount  257  is in the closed position, rests in the annulus between the discharge spout  43  and the outer wall  42  of the discharge funnel  40 . The outlet piercer  254  folds back the cut laminate  105  into the annulus. Thereby both the outlet piercer  254  and the cut laminate  105  are held out of the way of the discharged beverage. 
     The outlet piercer  254  is surrounded by a ledge  254   a  which is raised relative to its surroundings by 0.5 mm. 
     Advantageously, the outlet piercer  254  is removable from the lower part  255  to enable it to be thoroughly cleaned, for example, in a dishwasher. The removable outlet piercer  254  is received in a recess  267  in the lower part  255  where it is seated. The inlet piercer  253  and/or the outlet piercer  254  may be made of a metal, such as stainless steel, or from a plastics material. Advantageously, the use of plastic cutting elements is enabled by use of a laminate which is able to be punctured and cut by a non-metallic material. Consequently, the piercers  253 ,  254  can be made less sharp which lowers the risk of injury to the consumer. In addition, plastic piercing elements are not prone to rust. Preferably, the inlet piercer  253  and the outlet piercer  24  are formed as a single, integral unit which is removable from the lower part  255 . 
     In use, the upper part  256  of the cartridge holder  251  is movable from an open position in which it is orientated vertically or towards the vertical as shown in  FIG. 36 , to a closed position in which it is orientated substantially horizontally and in interengagement with the fixed lower part  255  and cartridge mount  257 . The upper part  256  is moved from the open to the closed positions by operation of the clamping lever. To close the upper part  256  a user takes hold of the clamping lever by the U-shaped arm  281  and pulls downwards. Consequently, the upper part  256  rotates which first brings the rim  311  of the viewing window  312  into contact with the flange  35  of the beverage cartridge  1  in the cartridge mount  257  and the window  312  itself into contact with the closed top  11  of the cartridge  1 . Continued rotation of the upper part  256  rotates the upper part  256  and cartridge mount  257  down into contact with the lower part  255 . Further rotation of the U-shaped arm  281  causes the U-shaped arm  281  to rotate relative to the upper part  256  and the lower part  255  resulting in the hook members  287  of the upper part  256  engaging the bosses  259  of the lower part  255  with the cam surface  288  riding over the bosses  259 . During this last stage of rotation the cartridge  1  is compressed between the cartridge mount  257  and the viewing window  312 . As a result, the viewing window  312  is moved axially relative to the circular body  310  of the upper part  256  against the bias of the wave spring. This movement allows for a take up of tolerances in the beverage cartridge  1  and beverage preparation machine and ensures that the amount of compressive force applied to the cartridge is kept within an acceptable range. The clamping force of the mechanism as moderated by the action of the wave spring ensures a clamping pressure on the cartridge of between 130 and 280N. Preferably the force is approximately 200N. A force less than about 130N does not provide an adequate seal, whilst a force greater than about 280N leads to plastic failure of the components of the cartridge  1 . During closure of the cartridge head the laminate  5  of the cartridge  1  is tensioned as it is brought into contact with the ledge  254   a  surrounding the outlet piercer  254  which causes the laminate  5  to flex out of plane as the distal end of the outer tube  42  of the cylindrical funnel is moved upwardly by 0.5 mm relative to the flange  35 . This movement also ensures that the great majority of the compressive force applied to the cartridge acts through the central region of the cartridge  1  through the load-bearing inner member  3 . In the closed position the cartridge  1  is thus clamped around the flange  35  by means of the rim  311  of the viewing window  312  and firmly clamped between the closed top  11  of the cartridge and the outer tube  42  of the inner member  3  by contact with the viewing window  312  and the ledge  254   a . These clamping forces help prevent failure of the cartridge  1  during pressurisation and also ensure that the inner member  3  and outer member  2  are fully seated relative to one another and thus that all internal passageways and apertures remain at their intended dimensions even during internal pressurisation. 
     An imaginary datum line can be drawn between the first and second pivot points  283 ,  285  of the cartridge holder  251 . As can be seen in  FIG. 41 , in the open position the third pivot points  286  are located on the side of the datum line nearest the fixed lower part  255 . As the upper part  256  reaches the closed position, the third pivot points  286  of the clamping lever pass through the datum line joining the first and second pivot points  283 ,  285  to the opposite side of the line, furthest from the fixed lower part  255 . Consequently, the U-shaped arm  281  ‘snaps through ’ from a first stable position to a second stable position. The snap through action is accommodated by shortening of the over-centre arms  282  and consequential compression of the resilient sleeves  282   c . Once the third pivot points  286  are past the imaginary datum line then recovery of the resilient sleeves  282   c  acts to continue the motion of the third pivot points  286  away from the imaginary datum line. The clamping lever thus has a bi-stable operation in that the lever is stable in the open or closed positions but unstable at the point when the third pivot points  286  lie on the imaginary datum line joining the first and second pivot points  283 ,  285 . Thus, the snap-through action of the clamping lever provides a positive closure mechanism which leads to a definite closure action wherein in the final stages of the clamping lever&#39;s rotation, the snap-through action of the U-shaped arm  281  and second arms  284  forces the hook members  287  firmly into engagement with the bosses  259 . In addition, the resilient sleeves  282   c  provide a resistance to re-opening of the upper part  256  since a minimum force is required to compress the sleeves  282   c  sufficiently to move the third pivot points  286  back into line with the datum line joining the first and second pivot points  283 ,  285 . Advantageously, the interengagement of the hook members  287  and the bosses  259  prevents separation of the upper and lower parts other than by rotation of the clamping lever. This is useful in preventing opening of the cartridge head  250  during operation when the cartridge head  250  is subject to internal pressurisation. 
     The purpose of the cartridge recognition means  252  is to allow the machine  201  to recognise the type of beverage cartridge  1  that has been inserted and to adjust one or more operational parameters accordingly. In a typical embodiment, the cartridge recognition means  252  comprises an optical barcode reader which reads a printed barcode  320  provided on the laminate  5  of the beverage cartridge  1  as shown in  FIG. 45 . The barcode  320  is formed from a plurality of bars of contrasting colour. Preferably the bars are black on a white background to maximise the contrast. The barcode  320  is not required to conform to a published standard but a standard format for barcodes, such as EAN-13, UPC-A, or Interleaf  2  of  5  may be used. The optical barcode reader comprises one or more LEDs  321  to illuminate the barcode  320 , a focusing lens  322  to acquire an image of the barcode, a charge coupled device (CCD)  323  for producing an electrical signal representative of the acquired image and support circuitry for the LEDs and CCD. The space in the lower part for accommodating the barcode reader is limited. A mirror or mirrors  324  may be used to reflect the light from the LEDs  321  to a focussing lens which is not located in the lower part  255 . Schematic arrangements are shown in  FIGS. 44   a  and  44   b . The lower part  255  comprises an aperture  326  which is the same size as the barcode  320  on the beverage cartridge  1 . In use the electrical signals produced are decoded by signal processing software and the results forwarded to the control processor. The software can recognise whether the read of the barcode contained errors. The barcode  320  may be rescanned a number of times before an error message is presented to the consumer. If the machine  201  is unable to read the barcode the consumer is able to use the beverage cartridge  1  to dispense a beverage using a manual mode of operation. 
     The cartridge head  250  also includes a cartridge sensor for detecting whether a cartridge is present in the cartridge holder  251 . 
     The cartridge head  250  also includes a lock sensor which detects whether the cartridge holder  251  is properly closed. Preferably the lock sensor comprises a micro-switch which is triggered when the cartridge holder  251  is closed and locked. Preferably the cartridge sensor and lock sensor are connected in series such that the output of both sensors must be satisfactory, i.e. cartridge present and mechanism locked, before the operating cycle can be commenced. 
     Operation of the machine  201  comprises insertion of a beverage cartidge  1  into the cartridge head  250 , carrying out an operating cycle in which the beverage is dispensed and removal of the cartridge  1  from the machine. 
     The operational behaviour of the machine  201  is determined by software embedded in the control processor. Operation of the machine can be described in terms of ‘States’, wherein the machine  201  will normally exist in a particular State until an event occurs to change the State, a step called a State transition. 
     Table 4 shows a State Transition Table which illustrates the States and State transitions for one embodiment of the beverage preparation machine  201 . 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 4 
               
               
                   
               
               
                   
                   
                   
                   
                 Cartridge 
                   
                   
                   
               
               
                   
                   
                   
                   
                 Sensor 
               
               
                   
                   
                   
                   
                 variable 
                 Water 
                 Water 
               
               
                   
                 State 
                   
                 Lock 
                 (OK, NOK, 
                 level 
                 flow 
               
               
                 State 
                 Description 
                 Temperature 
                 Sensor 
                 CLR) 
                 indicator 
                 rate 
                 StartStop 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 1 
                 WATER 
                 &gt;or = 85 goto 2 
                 Closed: 
                 N/A 
                 Low goto 
                 N/A 
                 No 
               
               
                   
                 HEATING 
                   
                 [Cartridge 
                   
                 10 
                   
                 Action 
               
               
                   
                   
                   
                 Sensor = readpod( )] 
               
               
                   
                   
                   
                 Open: 
               
               
                   
                   
                   
                 [Cartridge 
               
               
                   
                   
                   
                 Sensor = CLR] 
               
               
                 2 
                 WATER 
                 &lt;85 goto 2 
                 Closed: 
                 Cartridge 
                 Low goto 
                 N/A 
                 No 
               
               
                   
                 READY 
                   
                 [Cartridge 
                 Sensor = OK 
                 10 
                   
                 Action 
               
               
                   
                 If timeout 
                   
                 Sensor = readpod( )] 
                 goto 4 
               
               
                   
                 10 mins goto 9 
                   
                 Open: 
                 Cartridge 
               
               
                   
                   
                   
                 [Cartridge 
                 Sensor = NOK 
               
               
                   
                   
                   
                 Sensor = CLR] 
                 goto 3 
               
               
                 3 
                 READY TO 
                 N/A 
                 Open: 
                 N/A 
                 Low goto 
                 N/A 
                 Goto 5 
               
               
                   
                 BREW AUTO 
                 [temperature 
                 [Cartridge 
                   
                 10 
               
               
                   
                   
                 controlled in 
                 Sensor = CLR] 
               
               
                   
                   
                 background] 
                 goto 2 
               
               
                 4 
                 BREW IN 
                 N/A 
                 Open: 
                 N/A 
                 Low goto 
                 No 
                 Water off 
               
               
                   
                 PROGRESS 
                 [temperature 
                 [Cartridge 
                   
                 10 
                 flow 
                 goto 6 
               
               
                   
                 AUTO 
                 controlled in 
                 Sensor = CLR] 
                   
                   
                 goto 
               
               
                   
                 [Run Brew 
                 background] 
                 goto 10 
                   
                   
                 10 
               
               
                   
                 State] 
               
               
                   
                 goto 7 
               
               
                 5 
                 BREW 
                 N/A 
                 Open: 
                 N/A 
                 Low goto 
                 N/A 
                 Goto 5 
               
               
                   
                 SUSPENDED 
                 [temperature 
                 [Cartridge 
                   
                 10 
               
               
                   
                   
                 controlled in 
                 Sensor = CLR] 
               
               
                   
                   
                 background] 
                 goto 10 
               
               
                 6 
                 READY TO 
                 N/A 
                 Open: 
                 N/A 
                 Low goto 
                 N/A 
                 [Water 
               
               
                   
                 BREW 
                 [temperature 
                 [Cartridge 
                   
                 10 
                   
                 On] 
               
               
                   
                 MANUAL 
                 controlled in 
                 Sensor = CLR] 
                   
                   
                   
                 Goto 8 
               
               
                   
                   
                 background] 
                 goto 2 
               
               
                 7 
                 BREW IN 
                 N/A 
                 Open: 
                 N/A 
                 Low goto 
                 No 
                 Released 
               
               
                   
                 PROGRESS 
                 [temperature 
                 [Cartridge 
                   
                 10 
                 flow 
                 goto 7 
               
               
                   
                 MANUAL 
                 controlled in 
                 Sensor = CLR] 
                   
                   
                 goto 
               
               
                   
                   
                 background] 
                 goto 10 
                   
                   
                 10 
               
               
                 8 
                 PURGE 
                 N/A 
                 Open: 
                 N/A 
                 No action 
                 N/A 
                 No 
               
               
                   
                 [Water off; air 
                 [temperature 
                 [Cartridge 
                   
                   
                   
                 Action 
               
               
                   
                 on, timeout n 
                 controlled in 
                 Sensor = CLR] 
               
               
                   
                 sec then goto 
                 background] 
                 goto 10 
               
               
                   
                 9] 
               
               
                 9 
                 BREW DONE 
                 N/A 
                 Open goto 2 
                 N/A 
                 Low goto 
                 N/A 
                 Goto 9 
               
               
                   
                 [air purge] 
                 [temperature 
                   
                   
                 10 
               
               
                   
                 [Cartridge 
                 controlled in 
               
               
                   
                 Sensor = CLR] 
                 background] 
               
               
                   
                 if timeout 10 s 
               
               
                   
                 goto 2 
               
               
                 10 
                 STANDBY 
                 N/A 
                 Open: 
                 N/A 
                 Low goto 
                 N/A 
                 Goto 1 
               
               
                   
                   
                 [heater off] 
                 [Cartridge 
                   
                 10 
               
               
                   
                   
                   
                 Sensor = CLR] 
               
               
                   
                   
                   
                 goto 1 
               
               
                   
                   
                   
                 Closed: 
               
               
                   
                   
                   
                 [Cartridge 
               
               
                   
                   
                   
                 Sensor = readpod( )] 
               
               
                 11 
                 ERROR 
                 N/A 
                 N/A 
                 N/A 
                 N/A 
                 N/A 
                 N/A 
               
               
                   
                 Power off/on 
               
               
                   
                 required to 
               
               
                   
                 clear 
               
               
                 12 
                 WATER LOW 
                   
                   
                   
                 Low goto 
               
               
                   
                   
                   
                   
                   
                 10 
               
               
                   
               
            
           
         
       
     
     The following example illustrates an operating cycle to exemplify the use of the State Transitions by the control processor. 
     It is assumed that the machine  201  is initially switched off and with no cartridge  1  inserted in the cartridge head  250 . When the machine  201  is switched on the control processor is in State 1. The water heater  225  is switched on. Once the temperature reaches 85° C. the control processor transits to State 2. If at any time during State 1 or 2 the cartridge holder  251  is closed the lock sensor will be triggered to send a signal to the control processor indicating that the cartridge holder  251  is properly closed. The control processor then interrogates the cartridge sensor by sending a ‘readpod’ instruction. The cartridge sensor returns a signal to the control processor indicating whether a cartridge is in place in the cartridge holder  251 . If no cartridge is present the control processor transits to State 3 where it remains in a readiness state until the cartridge holder  251  is reopened at which point the control processor transits back to State 2. If a cartridge is present in State 2 then the control processor transits to State 4 and operation is commenced automatically. During States 4 to 9 the water temperature is controlled in the background to remain within the required tolerance range of the desired temperature as set by the operational parameters set by the barcode on the beverage cartridge  1 . Once the discharge stage of dispense is completed an air purge is commenced in State 8. Once the air purge is completed the operating cycle is completed and the machine enters to standby mode in State 10. If, during operation, an error occurs then the processor transits to State 11. If a low water level is detected then the processor transits to State 12. 
     To insert the cartridge  1  the cartridge holder  251  is opened as described above to expose the cartridge mount  257 . The cartridge  1  is then placed on the cartridge mount  257  received within the recess  290  such that the handle  24  of the cartridge is located in the irregularity  291 . The optical or magnetic barcode  320  of the cartridge  1  is orientated directly above the aperture  326  in the cartridge mount  257 . The cartridge holder  251  is then closed by operation of the clamping lever as described above. During closure the inlet and outlet piercers  253 ,  254  pierce the laminate  5  of the cartridge  1  to form the cartridge inlet  121  and outlet  122 . As described above the laminate  5  cut by the outlet piercer  254  is folded up into the annulus surrounding the discharge spout  43 . When closed the cartridge holder  251  grips the cartridge  1  around the rim  35  between the cartridge mount  257  and the upper part  256  and between the window  311  and the top  11  of the cartridge  1  to form a fluid tight seal of sufficient integrity to withstand the pressures developed during the operating cycle. 
     To commence the operating cycle the consumer operates the start/stop button  241 . 
     The operating cycle comprises the steps of cartridge recognition and the discharge cycle. 
     Cartridge recognition is performed by the optical cartridge recognition means  252  as described above assuming that the outputs from the cartridge sensor and lock sensor are satisfactory. Once the barcode  320  has been decoded the operational parameters of the machine  201  are adjusted by the control processor. The discharge cycle is then automatically commenced. 
     The discharge cycle has four main stages, not all of which are used for all beverage types: 
     (i) Pre-wet 
     (ii) Pause 
     (iii) Brew/Mixing 
     (iv) Purge 
     In the pre-wet stage the cartridge  1  is charged with water from the water storage tank  220  by means of the water pump  230 . The charging with water causes the beverage ingredients  200  in the filtration chamber  130  to be wetted. The charging may take place at a “fast” flow rate of 600 ml/min or a “slow” flow rate of 325 ml/min. The slow charging rate is particularly useful for cartridges containing viscous liquid beverage ingredients where the ingredients require some dilution before they are able to be pumped at a higher volume flow rate. The volume of water injected into the cartridge  1  is selected to ensure that water or beverage does not drip out of the cartridge outlet  122  during this stage. 
     The pause stage allows the beverage ingredients  200  to soak in the water injected during the pre-wet stage for a predetermined period of time. Both the pre-wetting and soaking stages are known to increase the yield of the extractibles from the beverage ingredients  200  and to improve the end flavour of the beverage. Pre-wetting and soaking are particularly used where the beverage ingredients are roast and ground coffee. 
     In the brew/mixing stage water is passed through the cartridge  1  in order to produce the beverage from the beverage ingredients  200 . The temperature of the water is determined by the control processor which sends instructions to the water heater  225  to heat the water passing from the water tank  220  to the cartridge head  250 . Water enters the lower part  255  of the cartridge holder  251  through the conduit  262  via the inlet valve and the inlet piercer  253  into the inlet chamber  126  of the beverage cartridge  1 . Brewing and/or mixing and subsequent dispensing of the beverage from the beverage cartridge  1  is as described above with reference to the versions of the beverage cartridge  1 . 
     The air purge comprises the blowing of pressurised air through the beverage preparation machine and the beverage cartridge  1  to ensure that all beverage is dispensed and that the flow path is cleared ready for dispensing another beverage. The air purge does not commence immediately on cessation of the brew/mixing stage to allow for the majority of the fluid to clear the flow path. This prevents an unacceptable spike in internal pressure on commencement of the air purge. 
     In normal operation a user manually stops the machine  201  by operating the start/stop button  241 . 
     Once the operating cycle has been completed the consumer removes the cartridge  1  by opening the cartridge holder  251  and manually removing and disposing of the cartridge. Alternatively, the machine  201  may be provided with an automatic ejection mechanism for removing the cartridge automatically on opening the cartridge holder  251 . 
     As described above, two or more of the beverage cartridges are used in combination according to the present invention to produce a wide variety of beverages including incorporating the advantage of dispensing a liquid dairy-based beverage portion from a cartridge of the same overall size as the cartridges used to prepare the remainder of the beverage. Thus a single beverage preparation machine may be used with all types of cartridges since the interface between the cartridges and the machine are the same irrespective of the beverage ingredients contained in the cartridges. 
     The delivery times for beverages using the machine  201  and cartridges  1  are typically between 10 and 120 seconds, preferably 30 to 40 seconds for roast and ground coffee, between 5 and 120 seconds, preferably 10 to 20 seconds for chocolate and between 5 and 120 seconds, preferably 10 to 20 seconds for milk. 
     The machine  201  may also advantageously comprise a memory in operative communication with the control processor that stores information on the type of beverage dispensed by a user. The operating cycle of the machine  201  may then be adjusted for the next cartridge  1 . This is especially advantageous where two or more beverage cartridges  1  are used sequentially to form a beverage. For example a coffee cartridge may be dispensed followed by a milk cartridge to form a cappuccino beverage. Alternatively a chocolate cartridge could be used followed by a milk cartridge to produce a creamy hot chocolate beverage. By using a memory that stores information on the first beverage dispensed, the manner of dispensing the second cartridge, say a milk cartridge, may be altered to achieve an optimum beverage. In the above example the milk dispensed for hot chocolate may, typically, be diluted less than the milk added to the coffee. In addition, the milk dispensed for chocolate may be dispensed at a slower flow rate to lessen the degree of foaming of the beverage. Many combinations of cartridges are possible and operating parameters as will be obvious to the skilled person. In addition, the memory may be used to allow the machine  201  to ‘predict’ the type of beverage that a user will next want to dispense. For example, if a user predominantly drinks one beverage type then the machine can instruct the water heater to remain at the optimum temperature for that beverage type.