Abstract:
This disclosure relates to improvements in beverage/food product preparation systems and in particular to beverage/food product preparation systems comprising machines of the type which use pre-packaged cartridges containing beverage or food ingredients. The cartridge ( 30 ) contains one or more beverage or food ingredients for use in a machine for preparing a beverage or food product from said ingredients. The cartridge ( 30 ) comprises a base ( 34 ), an outlet aperture ( 37 ) in the base ( 34 ), and a collar ( 38 ) extending from the cartridge base ( 34 ) around the outlet aperture ( 37 ). The cartridge ( 30 ) is inserted into a holding receptacle ( 14 ) of a machine the collar ( 38 ) interacts with an element ( 65 ) of the machine and the collar ( 38 ) is configured to determine the pressure in the cartridge ( 30 ) during the preparation process.

Description:
[0001]    This disclosure relates to improvements in beverage/food product preparation systems and in particular to beverage/food product preparation systems comprising machines of the type which use pre-packaged cartridges containing beverage or food ingredients. 
       BACKGROUND  
       [0002]    Beverage preparation systems typically comprise a beverage preparation machine and disposable cartridges (also known as pods or capsules) for forming single servings of beverage. The cartridges for use with such systems are pre-packed with beverage ingredients and are sealed prior to use. In use the cartridges are pierced during or after insertion into the beverage preparation machine so as to form an inlet for aqueous medium, such as water, to enter the cartridges and beverage to exit the cartridges. The use of such systems can be extended to the preparation of certain types of food products, such as milk based desserts and the like. 
         [0003]    Most of the machines require specially designed cartridges of a complex design and a particular specification of materials to cope with the high pressures involved in the preparation process, especially for espresso beverages as it is generally the internal geometry of the cartridge which enables the desired quality of the beverage/food product to be produced under high pressure. 
         [0004]    Alternatively the preparation parameters have to be preselected by the operator. 
         [0005]    It is now proposed to use the interface between the cartridge and the machine to determine the parameters of the preparation process, such as the pressure. 
       SUMMARY  
       [0006]    Accordingly, the present disclosure provides a cartridge containing one or more beverage or food ingredients for use in a machine for preparing a beverage or food product from said ingredients; 
         [0007]    said cartridge comprising a base, an outlet aperture in the base, and a collar extending from the cartridge base around the outlet aperture; 
         [0008]    wherein when the cartridge is inserted into a holding receptacle of a machine the collar interacts with an element of the machine and the collar is configured to determine the pressure in the cartridge during the preparation process. 
         [0009]    The cartridge collar preferably comprises one or more gaps which may be formed by castellations in the cartridge collar. 
         [0010]    Alternatively the cartridge collar comprises no gaps. 
         [0011]    Preferably the cartridge outlet aperture is sealed by sealing means prior to use. 
         [0012]    The present disclosure also provides a machine for preparing beverage or food products from a cartridge containing one or more ingredients, said machine comprising: 
         [0013]    a holding receptacle for receiving and holding a cartridge during the preparation process; 
         [0014]    preferably the machine element comprises wherein the machine has an element which interacts with the collar of the cartridge when the cartridge is inserted into the holding receptacle; 
         [0015]    such that collar is configured to determine the pressure in the cartridge during the preparation process by virtue of it&#39;s interaction with the machine element. 
         [0016]    valve means located downstream of the holding receptacle, which valve means open at a predetermined pressure, said valve means comprising a piston normally biased into a closed position in which it is contactable with the collar of a cartridge inserted, in use into the holding receptacle. 
         [0017]    Preferably the machine element comprises valve means formed downstream of the holding receptacle, which valve means open at a predetermined pressure, said valve means being formed by the collar of a cartridge inserted, in use, into the holding receptacle and normally biased into its first position in which it is contactable with an element of the machine. 
         [0018]    Preferably the valve means further comprise piercing means for piercing the cartridge when it is inserted into the holding receptacle. 
         [0019]    The present disclosure also provides a system for preparing beverage or food products comprising a machine and at least one cartridge; 
         [0020]    The one or more gaps in the cartridge collar preferably cause the valve to open at a first pressure. 
         [0021]    The lack of gaps in the cartridge collar preferably cause the valve to open at a second pressure which is preferably higher than the first pressure. 
         [0022]    Preferably the piston is biased by spring means into the closed position. 
         [0023]    An upper surface of the piston may contact a lower surface of the cartridge collar when in the closed position. 
         [0024]    Preferably at least a portion of the upper surface of the piston and of the lower surface of the cartridge collar are angled at substantially the same angle to the horizontal. 
         [0025]    The piercing means are preferably provided with at least one means to provide a liquid flow path such that when the cartridge sealing means has been pierced liquid is able to flow from an interior of the cartridge, along the piercing means and into a chamber formed by the collar the sealing means and the upper surface of the piston. 
         [0026]    Preferably when a pressure in the chamber is greater than the spring force of the spring means, the piston moves out of contact with the collar into an open position. 
         [0027]    The present disclosure preferably provides a method of preparing a beverage or food product comprising the steps of: 
         [0028]    selecting a cartridge; 
         [0029]    inserting the cartridge into a holding receptacle of a machine; 
         [0030]    piercing the cartridge with the piercing means; and 
         [0031]    supplying a liquid to the holding receptacle so as to pass the liquid through the cartridge to form the beverage or food product. 
         [0032]    Whereas known machines, which utilise a valve assembly to modify the operating pressure, require the operating pressure variations to be set by manual or drive means or some form of recognition system, in this system it is the interface between the cartridge and the outlet of the machine which controls the operation of the valve. Consequently, if the external geometry of an element of the interface is changed, namely the cartridge collar, this can automatically effect the required pressure change, without the need for the user to do anything. Thus the machines can be manufactured with a predefined peak opening pressure, whereas the actual operating pressure is defined by the cartridge inserted into the machine. 
     
    
     
       DETAILED DESCRIPTION  
         [0033]    Preferred embodiments of a system for preparing beverage and food products will now be described, by way of example only, with reference to the accompanying drawings in which: 
           [0034]      FIG. 1  is a schematic diagram illustrating the system for preparing beverage and food products; 
           [0035]      FIGS. 2 and 4  are cross sectional side elevations of two cartridges used in the system of  FIG. 1 ; 
           [0036]      FIGS. 3 and 5  are pictorial views of the collars of the cartridges of  FIGS. 2 and 4  respectively; 
           [0037]      FIG. 6  is a cross sectional side elevation of the cartridge of  FIG. 2  in a schematic representation of a part of a machine of the system of  FIG. 1 ; and 
           [0038]      FIGS. 7 and 8  are cross sectional side elevations of the cartridge of  FIG. 4  in a schematic representation of a part of a machine of the system of  FIG. 1 . 
       
    
    
       [0039]    The system for preparing beverage and food products described herein comprises a machine for preparing beverage and food products and one or more cartridges containing one or more beverage or food ingredients for use in the machine. In order to cater for a selection of beverage and food types, requiring different pressures during the preparation process, the interface between the machine and the cartridge is such as to enable beverage and food products to be prepared at at least two, and more preferably a range of, different pressures without user intervention. This is preferably achieved by providing the machine with a valve downstream of where the cartridge is located and operation of the valve is determined by the interface between the cartridge and the valve, as described below. 
         [0040]    The system  1  for preparing beverages or food products is illustrated schematically in  FIG. 1 . The machine part of the system  1  generally comprises a reservoir  10  for a liquid. Although water is likely to be the most common liquid used in preparing beverages such as coffee, the machine is also capable of handling other liquids, such as milk or milk preparations, for mixing with the beverage or food ingredients. Any references herein to water should also be taken to include any form of liquid used in preparing beverages or food products. The reservoir  10  is fluidly connected to a pump  11 , via a flow meter  12 , which in turn is connected to a water heater  13 . The water heater  13  is fluidly connected to the brew head  14 . It should be noted that the system of the present disclosure is not limited to preparing products which must be “brewed”; the use of the term “brew head” is for convenience only as it originated from machines which were limited to brewing beverages. The brew head  14  includes a cartridge recognition device  15 , which will be described in more detail below. 
         [0041]    A valve  16  is located in the conduit which provides the fluid path between the water heater  13  and the brew head  14 . The valve  16  may be an expansion/contraction valve. If the pressure of the liquid flow is acceptable, the liquid is passed to the cartridge  30 . If the pressure is below or above predetermined limits then the liquid flow can be prevented by the valve. 
         [0042]    The brew head  14  generally comprises a cartridge holder (not shown) for holding, in use, a cartridge  30 . The brew head  14  further comprises means, such as inlet and outlet piercers, for forming in the cartridge  30 , in use, an inlet for liquid to enter the cartridge  30  and an outlet for the prepared beverage to exit the cartridge  30 . 
         [0043]    The flow meter  12 , the pump  11 , the water heater  13  and the brew head  14  (and other components) are connected to an electronic controller  17 . In addition water temperature monitors  18 , 19  located at the inflow to and the outflow from the water heater  13 , are also connected to the controller  17 . 
         [0044]    The operational behaviour of the machine is determined by software embedded in the controller  17 , for example as described in EP-A-1440644. The memory of the control processor includes one or more variables for one or more operational parameters for the machine. These typically include the temperature of the liquid to be passed through the cartridge  30  during the operating stage, the optimum speed of charging the cartridge  30 , the presence or otherwise of a soak step, the total dispensed volume of the beverage or food product, the flow rate of the liquid during the discharge stage, and the period of the purge stage. 
         [0045]      FIG. 2  illustrates a first version of a cartridge  30  which is designed for use in preparing products which require low pressure during the preparation process, such as chocolate, coffee, tea, sweeteners, cordials, flavourings, alcoholic beverages, flavoured milk, fruit juices, squashes, sauces and desserts. A typical range of “low” pressures used for the preparation of such products is 0.5 to 2 bar.  FIG. 4  illustrates a second version of the cartridge  30  which is designed for use in preparing products which require high pressure during the preparation process, such as espresso-style products, where it is desirable to produce a crema. A typical range of “high” pressures used for the preparation of such products is 2 to 16 bar. 
         [0046]    The overall shape of the cartridges  30  is generally circular or disc-shaped. Typically the overall diameter of the cartridges  30  is 45 mm ±5 mm and the overall height is 40 mm ±5 mm. Typically the volume of the cartridges  300 ,  320  when assembled is 50 ml ±20% although this will vary according to the nature of the food or beverage ingredients contained therein. 
         [0047]    The cartridges  30  typically comprise a first member  31 , which generally comprises a bowl-shaped shell, having an annular wall  32 , an open mouth and a base  34 . The annular wall  32  and base  34  together define a receptacle having a chamber  35 . Beverage or food ingredients  33  are placed in the chamber  35  (see  FIG. 6 ) and the mouth is sealed with a second member  36  which provides a lid, using a suitable process, such as heat or ultrasonic welding. 
         [0048]    In the middle of the base  34  is an outlet aperture  37 , which is surrounded by an annular collar  38  which projects away from the base  34 . The collar  38  of the low pressure cartridge  30  ( FIG. 2 ) includes castellations  39  having gaps  39   a  therebetween. The collar  38  of the high pressure cartridge  30  ( FIG. 4 ) is solid and has no such castellations  39 . A lower surface  40  of the collar  38  is preferably at an inclined angle to the horizontal. 
         [0049]    Prior to use the outlet aperture  37  is sealed by a septum  41 , which is preferably integrally formed with the base  34 . 
         [0050]    Each member  31 ,  36  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 layer  42  of a gas impermeable material, such as EVOH, may be incorporated in the members  31 ,  36 . A suitable process for manufacturing the members  31 ,  36  would be injection moulding. 
         [0051]    The machine is preferably adapted to include a valve  50  located in the beverage/food product delivery outlet  20  to provide pressure control of the preparation process within the cartridge  30 . The valve  50  preferably comprises a retainer  51  which is mounted in the delivery outlet  20 . A lancet  52 , or other type of piercing device, is attached to the retainer  51  at one end  53 . The other end  54  of the lancet  52  is sharpened to provide means for piercing the septum  41 . The lancet  52  may be provided with one or more grooves  55  extending from the sharpened end  54  along a portion of the outer surface of the lancet  52 . 
         [0052]    Located around the lancet  52 , and moveable relative thereto, is a piston  56  having a central bore  57 . The bore  57  is stepped, having a narrower section  58 , through which the sharpened end  54  of the lancet  52  passes, extending towards the distal end  60  of the piston  56 , and a wider section  59  extending towards the proximal end  61  of the piston  56 . The resulting inward step provides a locating seat  62  for an end of a compression spring  63 , which is also located around the lancet  52  within the wider section  59  of the piston bore  57 . The other end of the spring  63  is mounted within the retainer  51 , so as to bias the piston  56  away from the retainer  51  towards the top of the beverage delivery outlet  20 . The bias of the spring  63  sets the breaking pressure of the valve  50 . 
         [0053]    As an alternative to the spring mechanism an elastomer may be used to bias the lancet  52 . 
         [0054]    The distal end  60  of the piston  56  comprises a radially extending flange  64 . An upper surface  65  of the flange  64 , or a portion thereof, may be angled downwardly (i.e. towards the perimeter of the flange  64 ), at substantially the same angle as that of the lower surface  40  of the collar  38 . An angled surface is preferable to a horizontal surface as it has the ability to self centre the piston  56  and creates a better geometry for shearing the liquid to create foam. 
         [0055]    Operation of the machine comprises insertion of a cartridge  30  into the cartridge holder of the brew head  17 , carrying out the preparation cycle in which the beverage/food product is prepared and carrying out a dispense cycle in which the beverage/food product is dispensed, and removal of the (substantially) empty cartridge  30  from the machine. 
         [0056]    When the cartridge  30  is placed in the cartridge holder in the brew head  14 , as shown schematically in  FIG. 6 , and the cartridge head closed, the lancet  52  is forced through the septum  41 , thereby piercing it, and opening up the cartridge outlet aperture  37 . The lower surface  40  of the collar  38  is forced into contact with the flange upper surface  65 . The spring  63  biases the piston  56  into a “closed position” in contact with the collar  38  and maintains a good contact between the surfaces  40 ,  65 . 
         [0057]    The preparation cycle typically has four main stages, although not all of these are used for all beverage or food types: 
         [0058]    1. Pre-wet 
         [0059]    2. Pause 
         [0060]    3. Brew stage 
         [0061]    4. Purge 
         [0062]    In the pre-wet stage the cartridge  30  is charged with liquid under pressure from the reservoir  10  by means of the pump  11 . An inlet piercer pierces the lid  36  to provide a flow path for the liquid to enter the cartridge and pass into the brew chamber  35 , where it mixes with the ingredients  33  contained therein. The charging with liquid causes the ingredients in the chamber  35  to be wetted. The charging may take place at a “fast” flow rate, e.g. of 600 ml/min, or a “slow” flow rate, e.g. of 325 ml/min. A slow charging rate is particularly useful for cartridges  30  containing viscous liquid ingredients where the ingredients require some dilution before they are able to be pumped at a higher volume flow rate. The volume of liquid injected into the cartridge  30  is selected to ensure that liquid or beverage/food product does not exit the outlet aperture  37  during this stage. 
         [0063]    The pause stage allows the ingredients to soak in the liquid 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 ingredients and to improve the end flavour of the final product and soaking are particularly used where the ingredients are roast and ground coffee. 
         [0064]    In the brew stage liquid is passed through the cartridge  30  in order to produce the beverage or food product from the ingredients  33 . The temperature of the liquid is determined by the controller  17 , which sends instructions to the heater  13  to heat the liquid passing from the reservoir  10  to the brew head  14 . Liquid enters the cartridge  30  and then passes into the chamber  35  of the cartridge  30 . Brewing and/or mixing of the product in the cartridge  30  occurs before the prepared beverage or food product exits the cartridge outlet, passes through the delivery outlet  20  and may be directed into a suitably placed receptacle  21 . 
         [0065]    The beverage or food product formed by passage of the liquid through the ingredients  33  passes out of the cartridge  30  through the outlet aperture  37  and down the lancet  52  to the other side of the pierced septum  41 . The grooves  55  help to provide a fluid flow path through the pierced septum  41 , especially where the septum  41  is made of a fairly stiff material so that the gap formed by the piercing is not much larger than the diameter of the lancet  52 . 
         [0066]    In the low pressure cartridge  30  ( FIG. 7 ), the gaps  39   a  between the castellations  39  of the collar  38  provide passages for the beverage or food product to flow on through into the delivery outlet  37 . 
         [0067]    In the high pressure cartridge  30  ( FIG. 8 ), there are no such gaps in the collar  38 . Therefore as the beverage/food product flows through pierced septum  41  along the lancet  52 , it collects initially in a chamber  66  which is formed by the side walls of the collar  38 , the unpierced part of the septum  41  and the distal end  60  of the piston  56 . This allows the pressure to build up inside the cartridge chamber  35 . When the pressure is sufficient to overcome the spring force, the piston  56  is forced away from the collar  38  into an “open position” thereby opening a gap  67  between the surfaces  40 ,  65  ( FIG. 8 ) to allow the beverage or food product to flow out into the delivery outlet  20 . 
         [0068]    During the purge cycle the temperature of the water heater  13  is raised sufficiently high to convert the liquid remaining in the system to steam and blowing the pressurised steam through the machine and the cartridge  30 . This ensures that all beverage or food product is dispensed and that the flow path is cleared ready for dispensing another beverage or food product. The purge cycle may not commence immediately on cessation of the brew/mixing stage to allow for the majority of the fluid to clear the flow path. 
         [0069]    Once the operating cycle has been completed, the machine automatically stops and the consumer removes the cartridge  30  by opening the cartridge holder and manually removing and disposing of the cartridge  30 . Alternatively, the machine may be provided with an automatic ejection mechanism for removing the cartridge automatically on opening the cartridge holder. 
         [0070]    The combination of the valve  50  and the external cartridge geometry, as provided by the collar  38 , thus enables the machine  1  to produce a variety of beverages or food products, as it allows the cartridges  30  to be selectively prepared at either high or low pressure during the preparation cycle, depending on the type of cycle required for the ingredients  33  in the cartridge  300 . However, unlike any of the prior art systems, the pressure required is identified by the external geometry of the cartridge  30  thus providing an automated variable pressure system. Such a machine is capable of producing beverages at a range of pressures, for example from 0 to 9 bar, and more preferably from 0 to 6 bar. 
         [0071]    Alternative configurations for the collars  38  may be used. For the low pressure cartridge  30 , the collar  38  need not be castellated, but may comprise one or more apertures, orifices or other form of gap in the side walls of the collar  38  which enables liquid to pass from the outlet aperture  37  to the delivery outlet  20 . 
         [0072]    In another embodiment, the spring loaded valve is incorporated in the cartridge collar  38 , rather than in the machine. Suitable spring means may be used to bias the collar  38  into contact with the upper surface  65  of a fixed element which replaces the piston  56 . When the requisite pressure in the chamber  66  is reached during the preparation process of a high pressure beverage or food product, the collar  38  is forced away from the fixed element, rather than the converse, to open the gap  67  between surfaces  40 ,  65 .