Patent Abstract:
A cartridge containing one or more liquid beverage ingredients and being formed from substantially air- and water-impermeable materials, the cartridge comprising an inlet for the introduction of an aqueous medium into the cartridge, a compartment containing the one or more liquid beverage ingredients and an outlet for a beverage produced by dilution of the one or more liquid beverage ingredients by the aqueous medium, characterised in that the compartment includes means for controlling dilution of at least a proportion of the one or more liquid beverage ingredients on introduction of the aqueous medium into the compartment.

Full 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 cartridge and method for the preparation of beverages and, in particular, using 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 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. Hence, there remains a requirement for a cartridge for the preparation of beverages wherein the cartridges and beverage preparation machine are suitable, in particular, for the domestic market in terms of cost, performance and reliability. 
   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. It has proven difficult to provide liquid dairy-based products in a cartridge due to the requirement to sterilise the cartridge components. Further, it has been found to be difficult to control the dilution and dispensing of the liquid milk products to arrive at a consistent and acceptable final beverage. 
   SUMMARY 
   Accordingly, the present invention provides a cartridge containing one or more liquid beverage ingredients and being formed from substantially air- and water-impermeable materials, the cartridge comprising an inlet for the introduction of an aqueous medium into the cartridge, a compartment containing the one or more liquid beverage ingredients and an outlet for a beverage produced by dilution of the one or more liquid beverage ingredients by the aqueous medium, characterised in that the compartment includes means for controlling dilution of at least a proportion of the one or more liquid beverage ingredients on introduction of the aqueous medium into the compartment. 
   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 cartridge of the present invention contains one or more liquid beverage ingredients suitable for the formation of a beverage product. The beverage product may be, for example, one of coffee, tea, chocolate, carbonated beverages, or a dairy-based beverage including milk. 
   Advantageously, the cartridge of the present invention provides superior dilution and dispensing of liquid beverage ingredients by ensuring that the liquid beverage ingredients are dispensed more evenly over the operating cycle rather that being dispensed all at the start of the operating cycle followed by substantially pure aqueous medium, which is, for example, water. This steady dispensation of the liquid beverage ingredients leads to improved homogeneity of the dispensed liquid beverage. In addition, where the diluted liquid beverage is subsequently subjected to foaming, by for example, jetting through an orifice, the improved homogeneity of the liquid leads to a greater consistency of foaming and improved quality and quantity of foam produced per unit volume of liquid beverage. 
   Preferably, the means for controlling dilution delays dilution of at least a proportion of the one or more liquid beverage ingredients on introduction of the aqueous medium into the compartment. 
   Preferably, in use, an aqueous medium flow path is established from the inlet to the outlet, the means for delaying dilution comprising a partition which hinders entry of at least a proportion of the one or more liquid beverage ingredients into the aqueous medium flow path. In one embodiment the partition comprises one or more apertures for controllably releasing the at least a proportion of the one or more liquid beverage ingredients into the aqueous medium flow path. Four apertures may be provided. 
   The partition may comprise a cup-shaped member having an open mouth directed away from the aqueous medium flow path. The cup-shaped member is preferably annular. The one or more apertures are preferably provided at or near a base of the cup-shaped member. The at least a proportion of the liquid beverage ingredients in the cup-shaped member, for example, drain by gravity through the one or more apertures in use. 
   In one embodiment, the cup-shaped member is spaced from a bottom of the cartridge, such that the aqueous medium flow path passes between the cup-shaped member and the bottom of the cartridge. Consequently, the at least a proportion of the liquid beverage ingredients in the cup-shaped member drains by gravity through the one or more apertures in use vertically downwards into the aqueous medium flow path. 
   Preferably, the cartridge comprises an inner member and an outer member, wherein the inner member comprises the cup-shaped member. The components of the inner member and the outer member may more easily be sterilised prior to assembly when they are separated. Once the components are conjoined a number of small-apertured, tortuous pathways are created which cannot effectively be sterilised using known methods. The ability to sterilise the components is a particularly advantageous feature where the cartridges are used for dispensing dairy-based beverages such as milk. 
   Preferably, the cartridge further comprises means for producing a jet of the beverage, wherein said means for producing the jet of the beverage comprises an aperture in the aqueous medium flow path. The aperture may be delimited by an interface between the inner member and the outer member. 
   Preferably, the cartridge further comprises at least one inlet for air and means for generating a pressure reduction of the jet of beverage, whereby, in use, air from the at least one air inlet is incorporated into the beverage as a plurality of small bubbles. At least one air inlet may be provided in the inner member downstream of the aperture. 
   In one embodiment the at least one air inlet and means for producing a pressure reduction in the jet of beverage produces a foaming of the one or more liquid beverage ingredients of greater than 40%. Preferably, greater than 70%. Preferably, the cartridge is disc-shaped. The outer member and/or inner member are formed, for example, from polypropylene. 
   In one example, the liquid beverage ingredient is a concentrated liquid milk composition. Preferably, the concentrated liquid milk contains between 25 and 40% total solids. More preferably, the concentrated liquid milk contains 30% total solids. Also preferably, the concentrated liquid milk contains between 0.1 and 12% fat. Alternatively, the one or more liquid beverage ingredients are selected from the group of cocoa solids, coffee, tea, sweeteners, cordials, flavourings, alcoholic beverages, flavoured milk, fruit juices, squashes, sauces and desserts. 
   The present invention also provides a method of dispensing a beverage from a cartridge containing one or more liquid beverage ingredients during an operating cycle, comprising the steps of passing an aqueous medium through the cartridge to form a beverage by dilution of said one or more beverage ingredients, and dispensing the beverage into a receptacle, wherein the one or more liquid ingredients as dispensed has a concentration at the start of the operating cycle of between 30 and 70% total solids and a concentration at the end of the operating cycle of between 1 and 15% total solids. 
   In one embodiment the concentration at the start of the operating cycle is between 30 and 35% total solids. The concentration at the end of the operating cycle is approximately 10% total solids. The liquid ingredient may be concentrated milk. In another embodiment, the concentration at the start of the operating cycle is between 60 and 70% total solids. The concentration at the end of the operating cycle is between 12 and 15% total solids. The liquid ingredient may contain cocoa solids. In another embodiment, the concentration at the start of the operating cycle is between 40 and 70% total solids. The concentration at the end of the operating cycle is between 1 and 2% total solids. The liquid ingredient may contain coffee. 
   The present invention further provides a method of dispensing a beverage from a cartridge containing one or more liquid beverage ingredients during an operating cycle, comprising the steps of passing an aqueous medium through the cartridge to form a beverage by dilution of said one or more beverage ingredients, and dispensing the beverage into a receptacle, wherein the one or more liquid beverage ingredients is foamed on dispense to a ratio of between 20 and 150%. 
   Preferably the one or more liquid beverage ingredients are foamed to a ratio between 70 and 100%. 
   The one or more liquid beverage ingredients may include one or more of concentrated milk, coffee and cocoa solids. 
   The present invention further provides a beverage as produced by the above methods. 
   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 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; 
       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, the fourth embodiment being according to 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 according to the present invention; 
       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   a  is a graph of concentration vs. operating cycle time; 
       FIG. 35   b  is a graph of foamability vs. operating cycle time; and 
       FIG. 35   c  is a graph of temperature vs. operating cycle time. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   As shown in  FIG. 11 , the cartridge  1  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  which will be described for background purposes 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  31  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 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  will now be described for background purposes with reference to  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  will now be described for background purposes and 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  embodying the present invention 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 bowl  100  joins the skirt portion  80  part-way up its length such that a discrete gap is provided between the bowl  100  and the laminate  5  when the cartridge is assembled. Thus, the apertures  85  are located below the level of the bowl  100 . As can be seen from  FIG. 34 , when the cartridge  1  is assembled and filled the bowl  100  contains a proportion of the liquid beverage ingredients therein, effectively partitioning that proportion of the beverage ingredients from the apertures  85 . 
   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. 35   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. 35   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. 35   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. 35   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 brewed 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 
             
             
                 
             
             
                 
               Brew 
                 
                 
                 
                 
             
             
               Sample 
               Volume (g) 
               Coffee 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 
               % Yield 
             
             
                 
                 
               (Cartridge A) 
               (Cartridge B) 
             
             
                 
                 
             
           
        
         
             
                 
               Mean 
               20.99 
               23.09 
             
             
                 
               Variance 
               0.77 
               5.04 
             
             
                 
               Observations 
               20 
               20 
             
             
                 
               Pooled Variance 
               2.90 
             
             
                 
               Hypothesized Mean Difference 
               0 
             
             
                 
               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 brewed 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 brew strength. 
   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.

Technology Classification (CPC): 0