METHOD, DEVICE, AND CAPSULE FOR PREPARING A FOAMY LIQUID FOOD
FIELD OF THE INVENTION
The present invention relates to the preparation of a liquid food from a capsule containing dry food substance. More particularly, the invention relates to a method for preparing a foamy liquid food such as a hot beverage with an enhanced head of foam that is obtained from mixing a diluent with soluble powder within a predosed capsule. The invention also relates to a device adapted for such a method. The invention also relates to a predosed capsule adapted for such a method.
BACKGROUND OF THE INVENTION
Foamed beverages such as espresso, cappuccino and latte prepared from dispensing machines are becoming more and more popular. Methods of preparation of such products from a predosed capsule are also known. The principle of using pre-metered and pre-packed portions of coffee and the like for the preparation of coffee-based beverages has the advantages to facilitate the preparation of the beverage while ensuring that the dose-to-dose quality and strength of the beverage remains constant for the same conditions of preparations (dosage, temperature, pressure, time, etc.). It also provides more convenience to the user. The capsule usually sits in a leak-tight enclosure of a special coffee-type machine and hot water is passed through the capsule under pressure. The underside of the capsule perforates under the build-up of pressure to release the extracted liquid. The use of roast-and-ground powder in capsules is commercialized to make coffee cups of high quality.
EP 0 512470 Bl describes a process for extracting sealed cartridges in a cartridge holder in which a mixture of water and air is injected into the cartridge under a pressure of 1 to 20 bar to deform the extraction face. The extraction face of the cartridge is deformed against a relief surface of the cartridge holder comprising relief elements and recessed elements, the extraction face tearing at the location of these relief elements and/or these recessed elements on reaching the breaking stress to enable liquid to be subsequently removed after extraction of the coffee under a pressure of 1 to 20 bar.
This process proves to be very effective for extracting a beverage liquid from an extractable, non-soluble material such as roast and ground coffee. Since the product is not soluble within the cartridge, the bed of material maintains an elevated inside resistance and pressure tends to build up to a relatively high range as more water enters the cartridge. The combination of high pressure, temperature and extraction time is key for extracting the fine aroma compounds from the coffee bed until the extraction face can tear to allow release of the extracted liquid in the cup.
For soluble products, water does not serve to extract solids and coffee aroma compounds but it is supposed to solubilize all the solids. Dilution of the solids is essentially obtained by thorough mixing within the capsule during a sufficient time up to a complete dilution. Furthermore, mixing should be carried out while entrapping sufficient air to form a good foam or froth upon releasing in the cup. Foam generation of soluble powder is complex and may also be dependent on the physical release conditions of the solution through the capsule. These physical conditions involve the level of shear created and pressure release through the openings. The building-up of pressure and the timing for release are also selected to obtain a sufficient mixing and air entrapment in the solution. The problem is that, when liquid starts entering the capsule, the powder starts dissolving and the solution tends to evacuate. As solids content in the capsule decreases, the resistance created by the powder in the capsule decreases proportionally. As a result, the solution tends to evacuate too quickly the capsule and at a too low pressure, without sufficient mixing having been carried out. As mixing is insufficient, lumps may form in the delivered solution, insufficient amount of air is entrapped and the resulting amount of foam created is poor.
US 3,292,527 to Stasse relates to an apparatus and a cartridge adapted to deliver in succession different drinks or beverages without allowing the drink or beverage to contact the basic elements of the apparatus. The cartridge may contain fine soluble powder and has a perforated bottom side that creates a pressure drop capable of retarding the outflow through the orifice. Such a perforated arrangement by itself, even when small, does not produce sufficient shear and does not retain sufficient pressure inside to be capable of generating a properly whipped or foamed beverage.
EP 0 468 080 to Fond also relates to a process of extraction of a cartridge for roast and ground coffee wherein the cartridge has an apertured bottom
side to deliver the extracted liquid along an extensive surface. This process is for roast-and-ground but would not properly apply to soluble powder such as instant coffee powder for the same reasons as for US 3,292,527.
WO 01/58786 to Halliday relates to a cartridge for the preparation of whipped beverages of "espresso" type in machines operating at low pressure characterized in that the cartridge incorporates in the beverage flow path, prior to or at the outlet, means for producing a jet of beverage, at least one inlet for air and means to generate a pressure reduction of the jet of beverage whereby in use air from the air inlet is incorporated into the beverage as a plurality of small bubbles. Due to the low pressure inside the cartridge, air must be added by specific air inlets. Such a cartridge specifically involves many parts and, hence, is tricky, complex and expensive to produce.
A need exists for a system to produce a food liquid, such as a coffee- based product, having superior whipped or foam characteristics obtained from a capsule-type system, and for the system to employ a relatively simple and low cost cartridge that can generate a substantially complete dissolution of the soluble food product and a high amount of foam.
SUMMARY OF THE INVENTION
The present invention satisfies these needs. The invention relates to a device for preparing a foamy liquid food from a capsule containing a premetered dose of food soluble substance or "predosed" capsule. The capsule intended for the device has an entry side adapted to be traversed by a flow of water entering the capsule, and a discharge side adapted to be traversed by a flow of beverage exiting the capsule. The device comprises water supply to provide water within the capsule. Water is provided through the entry side, mixes with the soluble substance in the capsule and a beverage is delivered through the discharge side. A beverage and foam conditioner is adapted to open the capsule for release of the beverage and to engage against the discharge side to hold pressure within the capsule so that the soluble substance can thoroughly mix with water and entrap gas within the capsule to dispense a foamy beverage.
Therefore, complete dissolution and foam generation assisted by an engagement member capable of holding pressure inside the capsule and controlling release of the beverage. The system of the invention holds the beverage within the
capsule until thorough mixing is obtained and sufficient gas is entrapped in the mixture to prevent release of the partially dissolved substance too early for complete dissolution. For physically achieving such an effect, the liquid and foam conditioner comprises at least one engaging surface adapted to create a tight surface contact with a certain area of the discharge surface of the capsule. As a result, a sufficiently retarded discharge of the beverage through the discharge side is created that benefits complete dissolution and the generation of foam.
The engaging surface is preferably of a convex shape adapted to conform to the surface area of the discharge surface by providing a tight fit between the engaging surface and the surface area of the discharge side. A tight fit ensures a flow resistance so that a pressure can be reached and maintained inside the capsule.
Preferably, the convex shape is adapted to form an inward deformation along a surface area of the discharge side. As resulting from such a deformation, the contact between the engaging surface and the discharge side is improved and made even tighter so that product within the capsule can be held until to achieve a better mixing up to complete dissolution and an effective gas entrapment. Due to the relatively high internal pressure created in the capsule, gas may be entrapped both in dissolved form as a liquid and in gas form, such as in small bubbles.
Preferably, the engaging surface is adapted to engage the discharge side along the surface area without creating substantial tearing between said engaged surface area of the discharge side of the capsule and the engaging surface of the device. The benefit of no substantial tearing by the engaging surface, particularly outside of the area immediately around the opening member, resides in that sufficient contact can be maintained between the discharge surface and the engaging surface to be able to properly retard release of the beverage. Therefore, the engaging surface has preferably a bulged profile as opposed to a sharp profile to avoid tearing of the discharge side. The profile may preferably be a bulged surface of dome-shape, preferably of an angle from 5 to 45 degrees as measured from the tangential to the base of the dome or to the plane perpendicular to the axis of the capsule. The engaging surface should engage along a sufficiently large area of the discharge side to properly control release of the beverage without risking to accidentally tear the capsule which would cause release of the beverage in an uncontrolled manner. Preferably, the engaging surface is adapted to deform a surface area of at least 30% of the whole discharge side of the capsule, even more preferably of from 50 to 90%) of it.
In order to better control release of the opening member, it is preferred that an opening member of the device is provided that is distinct from the engaging surface. The opening member engages the discharge side of the capsule to form an opening in the capsule capable of releasing the beverage out of the capsule. The opening member function is thus performed separately from the pressure holding function to ensure a more accurate control of the release. Therefore, the contact surface can be made extensive to properly hold the product inside the capsule while the discharge opening can be limited in size. An opening of limited size promotes shearing of the flow traversing the opening which, in consequence, contributes to generate a better foam in the cup.
In a first embodiment, the opening member comprises a puncturing member adapted to puncture a hole in the discharge side of the capsule. The puncturing member may be at least one cutting edge, a pin, or other member that perforates the material of the discharge side in a precise location point. Several puncture points may be envisaged but one seems to be enough according to the results of numerous tests carried out so far.
In an alternative, the device may also adapt to open a precut capsule. For that the opening member may comprise a finger adapted to open a capsule with a precut gate and wherein the finger is adapted to force opening of a precut gate of the capsule.
The capsule is preferably received in a capsule holder of a cup-shape that comprises the engaging surface and the opening member in its inner bottom side.
In a preferred embodiment, the engaging surface of the liquid and foam conditioner is disposed around the opening member. As a result, the outflow coming out of the opening in the capsule is restricted to some extent by the engaging surface that surrounds the opening. The restrictions created also participate more efficiently to hold the product longer in the capsule and generate additional shear stress on the beverage flow coming out of the opening.
A better control of the release and more shear stress can be performed when the engaging surface of the liquid and foam conditioner has a restricted passage for the liquid mixture. The restricted passage may preferably be channels, corrugations provided onto the engaging surface, or be obtained by a relatively high intrinsic roughness of the engaging surface, or combinations thereof.
A reservoir may also preferably be positioned in recess of the surface engagement member at the exit of the opening. The reservoir creates a separation between the opening member and the engaging surface. It also provides some clearance for the liquid to properly exit the capsule and air to enter the capsule. Its function is to form a buffer chamber for the liquid and to prevent cut fragments of foil of the capsule to block the restricted passages (i.e., channels, corrugations, etc.). The opening member preferably protrudes from the bottom of the reservoir such that the opening is carried out as the capsule deforms along the engaging surface and within the reservoir.
Water can be sullied to the inside of the capsule by piercing the entry side with at least one needle-like water injector. The water injector may have any suitable shape. The water injector may preferably have a piercing tip with water holders forming a certain positive inclination with the longitudinal axis of the injector to direct one or several flows of water in outward direction that promotes turbulence within the capsule. In an alternative way, for pre-opened capsules, water may also be supplied or injected through the discharge side without injectors being necessary but through simple water lines properly coupled to the pre-openings of the entry side of the capsule. The entry side may be the top side of the capsule or, alternatively, or in addition, may be the sidewall of the capsule. Therefore, water can be injected from different off-centered locations, e.g., the top side and/or sidewall, which cause vortex inside the capsule to enhance the powder mixing with water and gas.
The device of the invention comprises a holder for holding the capsule in a tight sealed manner to be able to carry out the preparation of the beverage within the capsule in a clean, fluid-tight sealing and pressurized way. The holder preferably comprises a removable lower holder member of cup shape that engages an upper supply water assembly adapted to cover the capsule. The lower holder member and upper water supply assembly together with a sealing member form a fluid-tight enclosure upon closing around the capsule. The lower holder and the upper seat member have complementary connections that enable to create a tight compressing sealing connection around the capsule. The connections may be of a ramp or bayonet type or any other suitable types.
A preferred method for preparing a foamy liquid food comprises: providing and retaining a capsule containing a dose of food soluble substance, wherein the capsule has an entry side adapted to be traversed by a flow of
water entering the capsule, a discharge side adapted to be traversed by a flow of beverage exiting the capsule, supplying water through the entry side within the capsule and mixing water with the food substance within the capsule, releasing the beverage while engaging a surface against the discharge side to hold sufficient pressure within the capsule so that the soluble substance can thoroughly mix with water and entrap gas within the capsule and, dispensing a foamy beverage.
In a preferred aspect of the method, engaging a surface against the discharge side is made by inwardly engaging a portion of the discharge side with an engaging surface, preferably a bulged surface, to create a tight contact without tearing of the discharge side as resulting from such a tight contact. Even more preferably, the bulged surface causes a deformation without tearing of the engaged portion of the discharge side of the capsule.
Preferably, beverage is dispensed by passing through the opening of the discharge side of the capsule, then, restrictions provided in the engaging surface and/or on the portion of the discharge side of the capsule in contact with the engaging surface. The restrictions are provided for controlling the release of beverage through the engaging surface, creating shearing and promoting foam generation. The restrictions may be channels, corrugations and the like.
Preferably, the opening of the capsule is made by puncturing in the discharge side of the capsule. In an alternative, the opening is made by a finger that pushes inward a precut member of the discharge side sufficiently to allow the beverage coming out of the capsule. Opening of the discharge side is carried out by at least one opening member that is distinct from the engaging surface that creates tight contact.
In another aspect, the invention relates to a predosed capsule adapted for the preparation of a foamy beverage according to the aforementioned method wherein, it contains a food soluble substance and comprises an entry side adapted to be traversed by a flow of water entering the capsule, a discharge side adapted to be traversed by a flow of beverage exiting the capsule wherein the discharge side is adapted to be opened by an opening member and to resist contact with the engaging surface to create a tight fit with the engaging contact to hold pressure within the capsule sufficiently and control release of a foamy beverage.
The capsule of the invention may be formed of a discharge side which has a plain wall adapted for puncture by a puncturing member of the dispenser to release the beverage. Such a capsule may be a fully closed capsule made of puncturable metallic or plastic material.
In an alternative, the capsule comprises a discharge side wherein at least one opening member is provided to open by a finger of the dispenser. Hence, the openable member may have a precut to ease the opening by the finger. Preferably, the openable member has at least one precut line. Preferably, the openable member comprises a plurality of precut lines arranged to form a pattern with solid regions against two adjacent precut lines. The finger preferably does not open widely the openable member but just holds the openable member in an open configuration, such as by pressing on inwardly on the openable member, with the openable member remaining attached to the discharge side by at least two slightly spaced apart solid regions. As a result, this enables to create just small passages for the beverage to release and a higher degree of shear stress is promoted.
In yet another embodiment, the capsule is pre-opened. The discharge side has at least two separate contiguous layers, each one having at least one passage for the beverage. The passage of one layer being spaced apart from the passage of the other layer. In such configuration, there is no need for a specific opening member of the device and, hence, product cross-contamination is reduced. These two layers may be sealed along the outer edge of the capsule. The offset passages and interface between the layers form a tortuous path for the beverage that both participate to the pressure building up inside the capsule when the engaging surface of the device contacts the discharge side and allow release of the beverage by providing shear stress at the interface of the two layers. Channels or other restriction could be added at the interface of the two layers, i.e., at least in the thickness of one of the layers, to promote shear stress and control pressure inside the capsule.
The discharge side can be made of a flexible and tear resistant material that withstands deformation without tearing upon contacting the engaging surface of the beverage and foam conditioner of the device. Preferred materials for the discharge side is aluminum or aluminum alloy or a laminate of plastic and aluminum, or even full plastic. The thickness of the discharge side may vary as a function of the material or laminate. For an aluminum based material, the thickness is preferably of from 5 to 100 microns, even more preferably of from 15 to 75 microns.
The capsule of the invention is conceived to serve as a mixing bowl for the powder to reconstitute a liquid beverage by thorough mixing with a diluent, preferably water or eventually milk, while entrapping sufficient gas that upon release at normal atmosphere generates multiple fine bubbles that confers an enhanced head of foam in the cup. For that, the enclosure of the capsule should be sized to address the powder capacity issue, as well as the gas capacity issue. An overall volume of the capsule's enclosure of from 20 to 100 cm , and 25 to 45 cm is preferred. The capsule should already contain a suitable amount of gas, such as air, O , CO2, N2 or any other inert gas or combinations thereof. Preferably, the ratio powder volume to gas volume ranges of from 1 : 50 to 1:1. Preferably, for coffee powder, the ratio powder volume to gas volume is preferably comprised of from 1 :50 to 1 :5, even more preferably 1 :30 to 1:10. For soluble high load powder including milk powder such as chocolate and cappuccino (also soup), the ratio powder volume to gas volume is preferably of from 1 :2 to 4: 1. More headspeace, i.e., a lower powder air volume, allows better initial powder dissolution especially for powders with lower solubility and/or generate viscous mass after it is mixed with water. With other types of food products, such as capsules with roast and ground coffee, where much of the content of the capsule is not dissolved upon the production of a beverage or other food product, the ratio of powder to gas volume can be above 5:1 or even 10:1.
In a preferred construction for the capsule, the capsule comprises a cup member that constitutes the entry side and sidewall of the capsule and a lid that constitutes the discharge side of the capsule. The cup member comprises a peripheral edge that extend outward the sidewall to form a connection surface for the lid constituting the discharge side. Connection of the lid along the edges can be carried out by any suitable pressure resistant structure such as an adhesion, a welding, a crimping, or a combinations thereof. The general shape of the capsule or cup member can take any suitable shape, such as frustoconical, cylindrical, pyramidal, cubic, etc.
Preferably, the outer surface of the discharge side has a passage oriented to control release of the liquid between the discharge side and the engaging surface.
The present invention allows the preparation of a liquid food from a capsule containing dry food substance. A method is provided for preparing a foamy liquid food such as a hot beverage with an enhanced head of foam that is obtained from mixing a diluent with soluble powder within a predosed capsule.
One embodiment of the invention is a system for preparing a liquid food. In the system, a containment portion is configured for containing a food ingredient and for receiving a liquid supplied to flow through in contact with the food ingredient to produce a liquid-food mixture. A boundary wall has a wall surface extending along a peripheral portion of the containment portion. Also, at least one elongated channel extends along the wall surface and disposed downstream of the containment portion for receiving the liquid mixture and directing the liquid mixture to an outlet for providing the mixture as a liquid food.
In the preferred system, the channel has a cross-section configured to create shear stress in the flow of the liquid mixture sufficient to create foam in the liquid food. The cross-section of the channel has a width and a depth that is at least 25%o of the width thereof, preferably at most about 150%, and more preferably around 100%.
The channel has a cross-sectional area normal to the flow of the liquid mixture of about between 0.01 mm and 2.25 mm , and more preferably less than about 1 mm2. Preferred dimensions of the channel cross-section are 0.1 mm to 15. mm of depth and width, more preferably less than about 1 mm, and most preferably between about 0.2 mm and 0.5 mm, with a preferred embodiment having 0.25 mm of depth and width. The channel may have a square cross-section, rectangular, or other shapes, including rounded and circular cross-sections with a radius in the ranges of depth and width listed above.
Preferably, the channel comprises a plurality of channels extending from a common area on the boundary wall. The channels have a length along that at least about an eighth of the dimension of the containment portion in the direction of the channel length, more preferably at least about a quarter as of said dimension. A preferred embodiment of the channel has a length of at least about 50% of the dimension of the boundary wall in the direction of the channel length.
The containment portion may comprise a food capsule that is receivable in an extraction chamber of a food preparation unit configured for feeding water into the capsule and comprising the outlet. The channel of this embodiment preferably comprises a slit extending partially through the boundary wall. A second wall can be disposed adjacent and substantially parallel to the boundary wall, with the channel formed by a slit extending substantially completely through one of the walls. Additionally, the food ingredient can comprise a predosed portion of a coffee, tea,
cocoa, or milk product, or a combination thereof, in an amount for preparing a single serving of a beverage.
The containment portion can also comprises an extraction chamber of a food preparation device, with the containment portion configured for receiving a capsule that contains the food ingredient. A liquid feeder is preferably configured for feeding liquid into the capsule in the extraction chamber, and the outlet is connected with the extraction chamber downstream of the channel and configured for delivering the liquid food product.
In an embodiment of the invention, the boundary wall is configured for supporting a capsule wall of the capsule that is disposed thereagainst when the capsule is pressurized with liquid. The boundary wall preferably includes a bulged portion surrounded by a recessed portion, with the bulged portion configured for deforming the capsule wall into the capsule for supporting the wall to reduce or prevent rupture thereof when the capsule is pressurized. A preferred bulged portion comprises a dome, and has a lateral width along the boundary wall that is at least one fifth of the lateral width of the boundary wall facing a face of the capsule, more preferably at least about one half, and most preferably at least about 75%), or the lateral width may be 100% thereof. Outlet openings of the extraction chamber downstream of the channel and outside and adjacent the bulged portion drain the liquid food to the outlet.
The system can be a beverage dispensing machine with the outlet configured for filling a drinking cup at a dispensing location. A hot water supply with a heater and a pump are preferably connected to inject the water into the capsule.
An embodiment of the invention includes an opening member disposed within the contour of the boundary wall and being configured for producing an opening in the capsule when the capsule is pressurized. The opening member can be configured for piercing the capsule wall. The opening member may alternatively be configured for displacing a moveable openable portion from a closed configuration in which the openable portion closes the capsule to an open configuration in which the capsule is open to release the mixture.
A reservoir is preferably provided in the extraction chamber within the boundary wall and in which the opening member is disposed. The reservoir is disposed fluidly communicated upstream of the channel and configured for receiving the liquid mixture from the capsule and feeding the mixture to the channel and
configured and dimensioned for allowing the maintenance of the supportive association between capsule wall and the boundary wall when the capsule is pressurized and the liquid is flowing out of the capsule. The reservoir allows the capsule to e opened without restricting the flow locally near the opening location, especially when the capsule is opened by piercing. The reservoir preferably has a lateral width of up to about 50%> of the width of the bulge portion or of the boundary wall, and more preferably between about 1/4 and 1/16 of the width or diameter. In a preferred embodiment, the reservoir is round and has a diameter of about 1/8 inches and a depth of about 1/8 inches. The preferred diameter or width is between about 1/16 inches and 1/4 inches, and the depth is preferably between about 1/32 inches and 1/8 inches, in dispensers where single servings or cups of a beverage are produced at a time.
The channel is preferably open at one longitudinal side thereof, such as the top side that is open to the interior of the extraction chamber, or if the channel is part of the cartridge, the side that faces out of the cartridge, although the channel in the cartridge may be provided in face thereof. The open side is preferably closed upon contact of the boundary wall with the wall of a food capsule or an extraction chamber, respectively, when the capsule is pressurized.
The channel is preferably open at one longitudinal side thereof, such as the top side that is open to the interior of the extraction chamber, or if the channel is part of the cartridge, the side that faces out of the cartridge, although the channel in the cartridge may be provided in face thereof. The open side is preferably closed upon contact of the boundary wall with the wall of a food capsule or an extraction chamber, respectively, when the capsule is pressurized.
Other features and advantages of the invention will become apparent from the following description in conjunction with the accompanying drawings provided solely by way of example.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a cross-sectional diagrammatic view of the device and capsule as positioned in the device in the beverage preparation stage;
Fig. 2 is a cross-sectional view of the holder of the device and the capsule when inserted in the holder before closure of the device;
Fig. 3 is a top view of the holder showing the beverage and foam conditioner;
Fig. 4 is a perspective view of a capsule of the invention;
Fig. 5 is a perspective view of a used capsule after beverage preparation;
Fig. 6 is a view of a capsule lid according to a variant of the invention;
Fig. 7 is a view of the capsule of Fig. 6 along line A-A;
Fig. 8 is a view of a capsule lid according to another variant of the invention;
Fig. 9 is a view of the capsule of Fig. 8 along line B-B;
Fig. 10 is a cross-sectional view of a capsule according to another variant of the invention;
Fig. 11 is a view of the inner layer of the discharge side of the capsule of Fig. 10;
Fig. 12 is a view of the outer layer of the discharge side of the capsule of Fig. 10;
Fig. 13 is a cross-sectional view of a capsule according to yet another variant of the invention;
Fig. 14 is a view of the inner layer of the discharge side of the capsule of Fig. 13;
Fig. 15 is a view of the outer layer of the discharge side of the capsule of Fig. 13;
Fig. 16 illustrate a graph of typical profiles of pressure, water flow rate and temperature during the preparation of a liquid food from a capsule and device of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to Fig. 1 to 3, the invention illustrates a device 101 for preparing a liquid food such as a beverage and the like from a single-use capsule 102. In this embodiment, the capsule 102 is a closed capsule that contains a dry food, preferably a substance that is soluble by addition of a diluent such as hot water, milk and the like to form a foamy, frothy beverage. Suitable foamy, frothy beverages are, for instance, coffee with crema, cappuccino with a milk based foamy head, late or cocoa. In the embodiment, the capsule 102 has a frustoconical shape with an inverted
cup part 120 and a lid part 121. The lid part 121 provides the discharge side of the capsule whereas the top 122 of the inverted cup part provides the entry side of the capsule. The cup part 120 has preferably a peripheral lip extending outwardly onto which is attached the edge of the lid part 121. The connection at the lip may be carried out by sealing or crimping or both. The shape of the capsule for the general purpose of the invention and the capsule could also take frustoellipsoidal, frustospherical or cylindrical shapes, as well as other suitable shapes.
The device comprises a cup-shaped holder 110 adapted to receive the capsule 102 in a suitable seat 111. The seat 111 has a bottom side comprising beverage and foam conditioner 112 adapted to open the capsule 102 for release of the beverage and hold pressure within the capsule. More particularly, the beverage and foam conditioner comprise a bulged engaging member 114 that protrudes slightly from the bottom surface 115 of the seat. The bulged engaging member 114 forms an engaging surface 116, as more apparent in Fig. 3, that is intended to snuggly engage a portion of the discharge side 121. The bulged engaging member has a general rounded profile of preferably large average radius. The configuration and geometry of the bulged member should be determined in the perspective of creating a tight contact with the underside of the lid when the capsule is pressurized with water without risk of tearing off the lid material along the engaging surface. The bulged member may provide a contact against 20 to 99%> of the total surface of the discharge side 121, preferably, 40 to 80% of the total surface. As preferred example, the bulged member has the following geometry: diameter "D" of from 20 to 70 mm, average radius of from 30 to 150 mm, maximum height (relative to surface 15) of
![Figure imgf000016_0001](https://patentimages.storage.***apis.com/fd/49/be/0bd69624cdbff6/imgf000016_0001.png)
In the center of the bulged member 114 is located an opening member
140 in the form of a small pin or needle that is intended to puncture a hole in the lid 121 of the capsule in a precise location. The pin or needle is located in a reservoir
141 that separates it from the engaging surface 116. The pin 140 may protrude from the bulged member or be flush with the bulged member or be even slightly inset relative to the bulged member. If the pin protrudes from the bulged member, the capsule can be perforated, or starts partially being perforated, at the time it is seated in the holder by the user since the pin is the first part of the holder entering into contact with the lid. If the pin is flush or inset, the capsule opens by the effect of the pressure building up within the capsule. The pin is relatively thin, with a tip configured for
puncturing the capsule, but preferably blunt enough to prevent the user from getting injured in case of contact with it. The pin's tip may be slightly rounded but still providing a suitable puncturing effect on the lid. More than one pin could be provided to increase the opening if necessary.
The reservoir 141 that surrounds the opening member 140 serves as a buffer part for the liquid to flow and to avoid blockage from the capsule punctured edges. The reservoir can be of a relatively small size, preferably 0.01 to 0.1 time the diameter of the engaging bulged surface D and of a depth of from 0.01 to 0.5 times the height of the bulged surface.
In order to release the pressure in a more controlled manner, channels 116 are provided at the surface of the bulged member 114 which preferably extend radially. The channels offer a privilege path for the liquid to flow between the engaging surface and the lid in a substantially radial direction. The channels preferably extend from the reservoir to the peripheral line of the bulged member as better shown in Fig. 3. The channels are between 101 and 108, preferably 102 to 104. The channels also produce additional shear stress on the liquid for increasing the production of froth on the liquid. Another equivalent pressure control device could replace the channels such as small corrugations or the rugosity of the bulged member could also be increased. The structure of the pressure control device should preferably be such that it does not substantially tear the lid.
The beverage exiting the capsule 102 finds its way out of the holder 110 by outlets 117, 118 that are situated in the bottom wall of the outlet, preferably at or close to the periphery of the bulged member. Channels 116 may be distributed in a preferred way to direct the flow through the outlets 117, 118 but this is not mandatory. The outlets could also be provided through the bulged member itself and made thinner and more numerous to replace the channels to create shearing on the liquid exiting the device.
Fig. 1 shows the capsule as in operational conditions of beverage preparation when the device is closed in a fluid tight relation around the capsule and water flows within the enclosure of the capsule. The device comprises an upper water supply assembly 103 adapted to cooperate in closure with the lower holder 110. A cup or bell-shaped member 130 of the assembly 103 is arranged to engage in closure the sidewall 120 and top wall 122 of the capsule down to the sealing ring 150 of the holder. More precisely, the lower edge of the member 130 holds on the lip 123 of the
cup shaped part of the capsule against the ring 150 placed underneath the lip. The bell like member is securely attached to an upper base member 131 of the assembly that supports at its periphery attachment 134 of ramp type complementary to the bayonet type portion 119 of the lower holder 110.
The water supply is carried out by a needle like water injector 132 with water outlets 133 arranged in such a way that the water is injected a few millimeter below the upper side 122 of the capsule and are thus remote from the pierced zone created by the penetration of the injector. The outlets may be disposed for directing water ejected from the injector at an outward orientation with a positive inclination angle θ relative to the longitudinal axis of the injector so as to promote dispersion of water as well as a vortex effect inside the enclosure of the capsule. In a possible variant (not shown), water could, as well, be injected from the sidewall of the capsule in one or more points.
Upon closing of the water supply assembly, the lid of the capsule tends to press on the bulged engaging surface so as to deform inwardly. Further deformation and tight contact are obtained after water is injected within the capsule and pressure has started to build up inside. Such a tight fitting between the discharge side of the capsule and the device enables to control and retard release of the beverage by holding sufficient pressure within the capsule until the soluble substance can thoroughly mix with water by creation of turbulence and vortex and, therefore, a sufficient amount of gas can be entrapped as resulting from these turbulence and vortex for a certain time.
The pressure inside the capsule may vary from 1 to 15 bar, preferably 4 to 10 bar. A pressure of at least 4 bar should preferably be maintained of from 10 to 30 seconds, preferably 10 to 20 seconds to enable the water and powder to thoroughly mix together and gas to be entrapped in the mixture in sufficient amount. The pressure is maintained sufficiently within the range, as defined, by a pump of the device that compensates for some liquid draining through the discharge side. However, the pressure can easily be maintained by the pump as resulting from the engaging surface retarding the liquid release in the cup. As the water pump is stopped, pressure in the capsule drops and the engagement of the discharge surface and bulged member decreases, i.e., the contact between the lid 121 and the dome surface 116 is loosen, thus promoting complete draining of the residual liquid food
through the opening of the discharge side. The profiles of pressure, water flow rate and temperature are shown in Fig. 16 as one achievable example.
Figs. 6 and 7 illustrate a possible variant of the capsule of the present invention in a configuration wherein the discharge side 121 of the capsule comprises an integrated openable member 124 against which a finger 140 of the device can act in pushing engagement to release liquid from the capsule. More preferably, the openable member is formed of at least one, preferably, a plurality of precut lines or slits 125. These precut lines or slits are adapted for release of the liquid once a pressure is exerted in the vicinity of them that would enlarge the section of the lines or slits. For example, these precut lines or slits 125 may be arranged to form a geometrical pattern such as a circular pattern, with solid regions 126 inserted between two adjacent precut lines or slits 125. Release of liquid is promoted by a pressure exerted by the finger having a smaller section against the openable member. The pressure exerted on the openable member tends to flex the openable member inward to enlarge the section of the slits sufficiently so that liquid mixture can drain therethrough. The dimension and configuration of the finger is determined to achieve a certain sufficient flexure of the openable member by the finger without breaking of the solid interconnecting regions so that the total opening area is sufficient for liquid release but maintained sufficiently small for creating shear stress and for limiting the risks of bits of material falling into the serving cup. The precut lines should be of a sufficiently small width, e.g., less than 200 microns, so that no significant amount of liquid could drain without a positive pressure exerted thereon by a finger of the device. In the present context, the "precut lines" refer to any local cutting zone made entirely or partially (e.g., weakening zones) through the thickness of the material of the discharge wall. If the precut lines are weakening zones, they should be able to break to form opening areas under the pressure exerted by the finger. The capsule of Figs. 6 and 7 is capable of fitting the beverage preparation device of Figs. 1 to 3, possibly with the central puncturing tip being replaced by a non-puncturing finger tip of suitable length and diameter, or a rough textured surface, to achieve the intended release function.
Figs. 8 and 9 show another possible variant of the capsule with the lid comprising a built-in passage(s) to control release of the liquid beverage at the interface between the engaging surface, e.g., the bulged member, and the discharge outer surface 121. These passages may comprise channels 127, 128 oriented from the
vicinity of the openable member, preferably from a cutting line 125, in a substantially radial direction therefrom. The orientation of the channels promotes the exit of the liquid beyond the engaging surface to ensure a sufficient flow of liquid while frothing the liquid. The passages could also be formed by corrugations or similar recessed or protruding structures preferably oriented in a similar direction. The passages on the capsule's surface can replace partly or wholly the passages located on the engaging surface. The passages could also be provided in a puncturable capsule.
Figs. 10 to 12 show yet another embodiment of the capsule with a discharge side or lid 121 comprising two adjacent layers 210, 211 sealed along the edge 123 of the capsule. Each layer has passages 212-214 for the beverage for the beverage to pass through the layers. The passages may include holes, slits or similar apertures. The passages 212, 213 of the internal layer are offset with respect to the passages 214 of the outer layer so as to create a tortuous path for the beverage through the discharge side 121. Channels 215, in shape of a straight line or any other curve configuration, may be added in one or the other internal surfaces of the layers, e.g., the internal surface of the inner layer 210, to create shear and control the desired pressure inside the capsule. As a result of this variant, there is no need for an opening member of the device and product cross-contamination can be significantly reduced accordingly. The beverage and foam conditioner of the preparation device can be simplified since only the engaging surface, i.e., the bulged surface, is retained to hold on the discharge side 121, but the opening member and reservoir are removed. Good results could also be obtained without using an engaging surface to support the discharge side provided the discharge side is of sufficient rigidity to support the internal pressure without breaking or tearing at the channels. The elongated channels are thus sized to maintain a certain pressure in the capsule, to create shear which forms the required amount of foam and to condition the bubbles' sizes (i.e., let only pass the thinner bubbles) in order to make a stable, dense and non "soapy" foam. The device may comprises a holding element on which the bottom edge of the capsule can take support while leaving the outlet 214 uncovered for a direct delivery of the beverage in the cup.
Figs. 13 to 15 show yet another embodiment in the same vain as the one of Figs 22 to 24. A difference resides in the number and location of the passages 216, 217 of the two layers. The inner layer may be built with only one passage 216 while the outer layer may have a single passage 217, both passages 216, 217 being
transversally offset one another. Good results could also be obtained without supporting the discharge side with an engaging surface provided the discharge side is of sufficient rigidity to support the internal pressure without breaking at the channels. In that case, the device comprises a holding element on which the bottom edge of the capsule can take support while leaving the outlet 217 uncovered for a direct delivery of the beverage in the cup.
While illustrative embodiments of the invention are disclosed herein, it will be appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments that come within the spirit and scope of the present invention.