HK1090527B - Methods and assembly for the preparation of a food product - Google Patents

Description

The present invention relates to a process for preparing a beverage from a substance contained in a container, and mixed with a liquid under pressure. In particular, the invention relates to such a process in which the substance is a soluble powder contained in a container such as a capsule.

The present invention also relates to a package and a capsule with an integrated injection nozzle enabling the implementation of the process of the invention.

The use of capsules containing a substance for the preparation of a drink by extraction or pressurised blending is well known, in particular in the field of espresso, tea or chocolate, and is particularly interesting for reasons of hygiene, freshness, preservation and ease of use.

There are different types of machines for preparing beverages from closed or permeable capsules containing a substance to be extracted such as ground coffee or tea, or a substance to be dissolved or dispersed such as soluble coffee, chocolate, milk or a mixture or simple combination of these substances.

The patent CH 605 293 describes a closed capsule. According to this patent, the capsule is shaped like a substantially truncated bucket with a collarette on which a metal membrane is thermoscelled. The membrane is filled with a filter and the capsule contains a certain amount of a substance for making a drink, typically ground coffee. When used, the capsule is placed in a device in which the bottom of the bucket is perforated in its center by an injection organ of a liquid under pressure.

An important aspect of this process is that the liquid flow must pass through the entire mass of the substance contained in the capsule to obtain optimal and reproducible extraction. To do this, the injection organ is in the form of a hollow needle in its center and has in the vicinity of its distal end a plurality of water outlet holes that exit laterally to allow the liquid under pressure to create a fluid piston to wet as much as possible the entire substance contained in the capsule, in the case of roasted and ground coffee.

In this respect, it was provided in patent EP 0 468 080 that the water outlet holes should be angled with the horizontal so that the injected water reflects off the bottom face before reaching the coffee bed to increase water dispersion.

It is therefore well known that the conditions of injection, mixing and wetting have a considerable influence on the quality of the beverage produced. Whether a substance is considered to be a substance obtained from a mill and compacted into a capsule or a substance to be dissolved or dispersed in a liquid such as a soluble coffee or a milk-based substance such as a cappuccino, chocolate or other, the way in which water flows through the capsule has an influence on the extraction or mixing conditions and therefore on the final quality of the beverage.whereas a soluble tea must dissolve without foaming. Dissolution or dispersion must be total, homogeneous, rapid and without clump formation or flocculation. For products to be extracted such as ground coffee, the optimal wetting conditions are different. The product must be completely wet, optimizing the water/coffee contact surface, and without creating preferred pathways for water through the coffee bed. Indeed, creating a preferred pathway through the coffee bed can lead to too sudden pressure rise and a too rapid release of the extract,The extraction time is insufficient and some of the coffee has not yet been properly soaked.

The processes and devices of the earlier art are well suited to extracting substances contained in a capsule such as roasted and ground coffee, but are poorly suited to capsules containing soluble substances such as a soluble coffee or chocolate powder.

The arrangement of the known means of liquid injection under pressure and the jets produced by these means do not allow, in particular, the necessary mixing to be achieved to dissolve the liquid soluble substance efficiently, so that a considerable part of this substance does not come into contact with the liquid and is not dissolved.

For example, the patent application EP 0449 533 A1 relates to packaging containing an edible product for the preparation of a beverage. Water is forced under pressure through slots arranged along a side wall delimiting a rectangular enclosure containing the edible product. The slots produce jets of water and a turbulent flow in the enclosure. However, the injection is perpendicular to the side wall and the jets are either perpendicular or parallel to each other. This results in turbulence but no whirling movements.

US Patent 5,906,844 relates to a filter coffee machine comprising a container for receiving a filter filled with coffee and a nozzle for wetting the coffee.

US Application 2003/005661 A1 concerns a capsule and its device in which inclined holes are made through the lid to cause turbulence.

It follows from the foregoing that there is a need for a process and a device for the preparation of a beverage, in particular from a soluble substance contained in an enclosure.

The main purpose of the present invention is therefore to satisfy this need by proposing a process for preparing a beverage from a soluble substance contained in a chamber which allows the substance to be completely dissolved.

The present invention is also intended to provide a process that is suitable for both capsules containing a substance to be extracted and capsules containing soluble substances.

Err1:Expecting ',' delimiter: line 1 column 148 (char 147)

The present invention also aims to provide a process for preparing a beverage from a substance to be extracted or soluble contained in an enclosure which is simple and inexpensive to implement.

The purpose of the invention is also to provide a device for the preparation of a beverage operating according to the process of the invention.

The purpose of the invention is also to provide a capsule for the implementation of the process according to the invention.

To this end, the invention relates to a process for preparing a beverage by injection of a liquid through a chamber containing a soluble and/or extractable food substance as defined in claim 1.

In a preferred embodiment of the process of the invention, the enclosure comprises a central axis and the liquid is injected at a distance from the central axis of the enclosure, so that the direction of the liquid jet passes away from the central axis in the transverse plane of the enclosure and normalises to this central axis and thus causes a swirling motion around this central axis of the enclosure.

The jet is thus preferably tilted advantageously towards the back wall of the enclosure.

Err1:Expecting ',' delimiter: line 1 column 606 (char 605)

This process allows the preparation of beverages from, for example, identical capsules, with a concentration of extracted or dissolved substances that varies very little from one capsule to another.

Another advantage is that when the soluble substance is mixed with the liquid injected, air is trapped in the mixture, which results in a bubbly drink.

Another advantage is that the process is simple and easy to implement.

This process also has the advantage of being applicable to a wide variety of food products.

The invention also concerns a set as defined in claim 12.

The invention also concerns a capsule containing a soluble and/or extractable food substance for the preparation of a beverage by injection of a pressurised liquid as defined in claim 24.

These characteristics enable the capsule to be used to implement the process of the invention with a conventional device comprising a simple liquid nozzle.

In a preferred embodiment of the capsule according to the invention, the upper wall comprises an outer wall element and an inner wall element together delimiting a cavity that is sealed from the outside and arranged to receive a punching and injection element, and a channel connecting that cavity to the injection assembly.

In this embodiment, the injection assembly preferably comprises a nozzle coming from a single part with the inner wall element. The cavity and the channel are advantageously formed in the inner wall element and the outer wall element is formed of a perforable membrane.

In a preferential mode, the chamber of the enclosure or capsule includes at least one revolution generator or at least no edge, such as an ellipse around the central axis thus defining a cylindrical, trunk and/or curved sidewall.

Other features and advantages of the present invention will be described in the following description of a preferred method of manufacture of the process and device according to the invention, presented as a non-limiting example by reference to the attached drawings, in which: Figure 1 is a schematic view in cut-off of a first embodiment of a device for preparing a drink by injection of a liquid through a capsule according to the invention, the preparation device being represented in the opening position; Figure 2 is a schematic view in cut-off of the preparation device represented in Figure 1, the preparation device being represented in the closing position; Figure 3 is a schematic view from the top of a capsule; illustrating in particular the position of the liquid injection point in it,The opening was omitted; Figure 4 is a schematic view in perspective of a perforating and injection element equipping the device of the invention represented in Figure 1; Figure 5 is a schematic view in perspective of a variant of the device for preparing a drink by injection of a liquid through a capsule according to the invention, the capsule holder having been omitted; Figure 6 is a schematic view in perspective of a second mode of manufacture of a device for preparing a drink by injection of a liquid through a capsule according to the invention, the first preparation device being represented in the closed position and according to a mode of use; Figure 7 is a schematic view of the preparation of the device in Figure 6.the preparation device is shown in the closed position and in a second mode of use;Figures 8a and 8b are schematically in perspective and in perspective cut-off views of the punching and injection element usable in conjunction with the second mode of preparation;Figures 9a and 9b are schematically in perspective and in perspective cut-off views of a punching and injection element usable in conjunction with the second mode of preparation;Figure 10 is a schematically in perspective cut-off view partially removed from a capsule according to the invention,and Figure 11 is a schematic view in perspective of a detail of the capsule shown in Figure 10.

In the following description, identical elements are indicated in the figures by the same numerical references.

Figures 1 and 2 show a device for preparing a beverage designated by the general numerical reference 1, the device being shown in the opening position in Figure 1 and in the closing position, i.e. in the use position, in Figure 2. In Figure 1, the beverage is prepared by injecting a liquid, typically hot or cold water under pressure, through a capsule 2 containing a food substance 4 (not shown) soluble and/or extractable such as ground roasted coffee, tea, soluble coffee, a mixture of ground and soluble coffee, a chocolate product or any other dehydrated food substance.

As can also be seen in Figure 1, capsule 2 has the general shape of a cup comprising a side wall 6 and a bottom wall 8 defining a bottom. In the illustrated example, the diameter of bottom 8 is less than the diameter of the cup opening. The free end of side wall 6 ends with a substantially annular peripheral rim 10 extending outwards from the cup. For reference, side wall 6 and bottom 8 are typically made of a plastic material chosen from the set including EVOH, PVDC, PP, PE, PA in single or multilayer.The cup is further sealed by an upper wall 12 formed by an operculum sealed on the rim 10 e.g. by thermal welding. The operculum 12 is typically made of a material capable of being perforated by means of perforation and injection of the device 1, which will be described in more detail below. The material of the operculum 12 may be chosen from the assembly comprising aluminium, an aluminium/plastic composite, a cardboard/plastic composite, cardboard/aluminium/plastic, a pure plastic or multi-layer. The side wall 6, bottom 8 and the operculum 12 together thus form a chamber 14 in which food substance 4 is contained.Err1:Expecting ',' delimiter: line 1 column 176 (char 175)

In the example shown, it will be noted that the capsule 2 has a thin film 16 in its lower part, which is sealed on an inner rim 18 of the cup and closes the chamber 14 in its lower part. This thin film 16 is placed on top of a disc 20 with a plurality of relief elements spaced regularly on the upper surface of the disc 20 and forming a plurality of channels leading to the periphery of the disc in a collection chamber 22 bounded by the disc 20 and the bottom 8, this collection chamber 22 leading outwards via a flow hole 24.The thin film 16 is intended to tear on contact with the raised elements under the effect of the pressure rise inside the chamber 14. It should be noted that the flow orifice is specific to capsule 2, which has the advantage of being able to deliver a product directly into a cup without direct contact with the device and ensures that there is no cross-contamination of the beverages, better hygiene, less cleaning and simpler design of the preparation device. For a more detailed description of the capsule 2, reference is made to Euro PCT patent application No 03/00384 filed on 13 January 2003 in the name of the applicant and the full contents of which are incorporated here.

The device 1 comprises a liquid injection head 26 of general cylindrical shape placed above a capsule holder 28 of general cylindrical shape. The injection head 26 and the capsule holder 28 are vertically moving relative to each other between the opening position (Figure 1) in which the capsule 2 can be placed in the capsule holder 28 and the closing position (Figure 2) in which the device 1 can be activated.

Specifically, the capsule 2 is placed in a housing 30 of the capsule holder which is typically of a complementary shape to the capsule it is intended to receive. The housing 30 includes at its bottom an opening 32 facing the outflow orifice 24 of the capsule 2. The capsule holder thus forms means of supporting the capsule 2 in the preparation device 1.

The injection head 26 consists of a support 34 having the general shape of a bell in the obvious 34a to which a core 36 is attached. The latter consists of a liquid inlet channel 38 which extends between a liquid inlet well 40 and a perforating and injection element 42 having an injection hole 42a. The perforating and injection element described in detail below is designed to pass through the operculum 12 and brings the injection hole 42a into the capsule of the relative movement of the head during injection 26 and the capsule 28 which brings the preparation carrier into the position of disposal.

The well 40 is intended to be connected to a liquid supply sleeve of an apparatus (not shown) capable of delivering hot or cold liquid under pressure. The injection head 26 thus forms an injection set capable of injecting a liquid in the form of a J-jet from at least one injection point defined by the injection orifice 42a of the punching and injection element 42.

In the example shown, clearance 34a is of a substantially cylindrical shape and its bottom 34b comprises a central opening 44 extended outwards axially by a wall defining a sleeve 46 threaded inwards.

The core 36 has a large cylindrical first portion extending into the 34a cavity and a smaller second portion screwed into the 46 sleeve. The injection head 26 also includes a ring seal 48 interposed between the first portion of the core 36 and the inner side wall of the 34a cavity. This seal 48 is arranged to rest, in addition to the closing position (Figure 2), against the capsule rim 10 which in turn rests on an upper capsule support surface 28a of the port 28. The 48 also protrudes axially from the 34a cavity to allow it to be compressed properly when coming into contact with the 48a cavity and to ensure proper perforation and re-sealing. In the example illustrated in the example 38 and the section of the 48a cavity, the sealing is shown as well as the peripheral seal.

Referring also to Figure 3 which is a top view of capsule 2 in which the aperture 12 has been omitted and in which only the perforating and injection element 42 of the injection head 26 has been represented, it is seen that the perforating and injection element 42 and more particularly its injection orifice 42a is arranged at a distance from the centre C of capsule 2 and is therefore eccentric with respect to the central vertical axis A-A of the capsule.This configuration of the position of the injection orifice 42a in the capsule and the particular orientation of the axis 50 of this orifice produces, when a liquid is injected, a jet J which creates in the capsule a movement of the swirling liquid around the centre C of the capsule accompanied in particular by multiple reflections of the jet against the inner walls of the capsule.

In order to obtain a mixing, or in other words to create an optimal vortex effect in capsule 2, the applicant found, first, that the axis 50 of the injection orifice 42a must form with the line 52 which connects the injection point to the central axis passing through the centre C of capsule 2 an angle between 20° and 60° and preferably between 35° and 45° and, second, that the axis 50 must form an angle β between 50° and 70° and preferably between 55° and 65° with the vertical axis A-A of the capsule.The angle a is measured in the transverse plane passing through lines 50 and 92, which is therefore orthogonal to the central axis AA. The angle β is measured in the plane passing through the central axis AA and the line 50. It has also been found that it is preferable to place the injection orifice 42a in the vicinity of the side wall 6 of the capsule in order to be able to gradually wet the substance from the edges of the capsule to the centre of the capsule and ensure that the entire substance comes into contact with the liquid.The injection rate is approximately 7 mm and the flow rate of liquid injected is approximately 4 ml/s.

In Figure 4 an example of the perforation and injection element 42 is shown in cutting, which is intended to pass through the aperture 12 by tearing it locally when the preparation device is in the closing position. The perforation and injection element 42 consists of a hollow needle with a channel 42b open at both ends.The inclination of the second section of the tube is identical to the angle at which the liquid is injected into the capsule in that the first section is significantly parallel to the A-A axis when the needle is mounted in the core 36. It is also shown in Figure 4 that the hollow needle forming the perforation and injection element 42 has a gap 42c in its distal part and that the injection orifice 42a opens on a side opposite to the gap 42c. This particular configuration of the gap of the needle makes it advantageous to push the gap 12a portion of the needle torn to the side of the opening when the needle is penetrated through the gap 42c, although the gap is not always completely disturbed and the injection of the liquid into the 12a portion of the capsule is not always completely disrupted.

In a variant not represented, the punching and injection element 42 may also be surrounded by a seal to keep the chamber sealed from the outside in the position of use of the preparation device.

Of course, the injection hole 42a is arranged so that the liquid injection takes place a few millimetres below the 12th operculum, typically 4 mm.

Figure 5 shows a schematic view of a variant of the device 1 for preparing a drink by injection of a liquid through a capsule of the invention in which only the injection head is represented. According to this variant, the capsule holder is identical to that described above in connection with Figures 1 and 2, while the injection head 26 no longer comprises a single punching and injection element 42 but a plurality of these latter, in this case three, each having an identical structure and orientation to the punching and injection element 42 described in connection with Figures 1 to 4.In particular, the three punching and injection elements 42 are arranged evenly on a lower surface of the injection head 26 to cooperate with the operculum 12 of capsule 2 in the position of use of the preparation device.

A second mode of preparation of a device for preparing a beverage by injection of a liquid through a capsule of the invention is shown in Figures 6 and 7. The preparation device is shown in the closed position in these two figures, but in a first mode of use in Figure 6 and in a second mode of use in Figure 7.

In Figure 6 the preparation device is shown in a first wet mode in which the liquid is injected into the capsule in such a way as to create a swirling motion of the liquid around the centre C of the capsule accompanied in particular by multiple reflections of the jet against the inner walls of the capsule as described above in conjunction with Figures 1 and 2.

In Figure 7 the preparation device is shown in a second wet mode in which the liquid is injected into the capsule in such a way as to create, in addition to a swirling movement of the liquid around the centre C of the capsule, a wet in the upper part of the capsule by means of a divergent jet of liquid in the form of a thin layer of liquid to wet the substance contained in the capsule from above.

According to this second embodiment, the preparation device consists of a perforating and injection element 60 comprising a first injection orifice 62 arranged and oriented identically to the injection orifice 42a of the perforating and injection element 42 described in conjunction with Figures 1 to 4, and a second injection medium 64 whose injection axis extends significantly horizontally to produce the divergent jet in the form of a thin liquid layer.The perforating and injection element is extended at the opposite end to the injection means 62 and 64 by a 60c operating finger cooperating with a lever 68 controlled by (unrepresented) joint switch means of the head 26. The perforating and injection element 62 comprises in its median part a larger diameter portion in which the opening 66 is reserved and by which it is mounted in translational mobility in a 70 shouldered passage parallel to the vertical axis of the reserved injection head in the core 36,Two O-ring joints are placed on either side of the opening 66 on the punch and injection element 60 to cooperate with the inner surface of the punch and injection element 70.

In this embodiment, the punch element 60 is mobile between two distinct positions, namely a first position (Figure 6) in which only the first orifice 62 exits the capsule 2 and which corresponds to the first mounting mode and a second position (Figure 7) in which the first orifice 62 and the second injection medium 64 exits the capsule 2 and which corresponds to the second mounting mode. The switch from the first injection mode to the second mounting mode is made via the switching means which act on the punch and injection mode 60 against the spring of 72 via the lever.

Preferably, as shown in Figures 8a and 8b, the second injection medium 64 for producing a divergent jet in the form of a thin liquid layer comprises a plurality of 64a orifices spread over part of the perimeter of the perforation and injection element 60. As the perforation and injection element 60 is placed eccentrically inside the capsule, and more specifically in the vicinity of the side wall of the capsule, the 64a orifices are directed towards the centre of the capsule. For reasons related to the manufacture of the liquid layer 60, the 64a orifices are advantageously displaced in height from each other. These 64a orifices thus produce a plurality of divergent jets to form a thin liquid layer and thus descend into the upper part of the capsule.

Of course, it may also be considered to form the thin liquid layer from a single slot-shaped hole 64b extending transversely in the longitudinal direction of element 60 as shown in Figures 9a and 9b. In this case, the divergent jet extends over a circular area large enough to noticeably wet the entire substance in the upper part of the capsule.

It should be noted that orifices 64a and 64b are respectively arranged so that the thin liquid layer is produced in a substantially continuous manner over an angular area between 90° and 180° and preferably in the order of 160°. Furthermore, these orifices 64a and 64b are arranged to produce a liquid layer with a thickness of 0.5 mm or less and preferably less than 0.3 mm. To this end, a diameter of 0.5 mm is preferably chosen for each of the orifices 64a and a diameter of 0.7 mm is preferably chosen for orifice 64b.

In a favourable variant of this second method, the axis of the second injection medium 64, i.e. the axis of the orifices 64a and 64b respectively, which define the direction of the liquid jet, makes an angle between 0° and 25° with the horizontal and preferably an angle of about 15°. The liquid injected through these orifices is thus directed upwards and reflected first against the lower surface of the operculum 12 and is then returned to the bed of substance with much greater dispersion.

In Figure 10 a capsule 100 containing a food substance 4 soluble and/or extractable for the preparation of a beverage by injection of a liquid under pressure is shown and which can implement the process of the invention with a conventional type apparatus including a simple liquid dispensing nozzle. To this end, the capsule 100 differs from the capsule 2 described in conjunction with Figures 1 and 2 in that the upper wall 110 comprises an injection set 112 configured to inject liquid into chamber 14 from an injection point in the form of a jet J, the injection point and the direction of the said jet J being configured in such a way that in said capsule a turbulent movement is created which creates a mixing with said liquid.

In particular, the upper wall 110 comprises an outer wall element 114 and an inner wall element 116 which together delimit a cavity 118 that is watertight to the outside and a channel 120 which connects cavity 118 to the injection set 112.

The outer wall element 114 is made of an operculum with at least one region made of a material capable of being perforated by a perforating and injection element (not shown) such as an injection nozzle of a conventional beverage brewer.

In this embodiment, the cavity 118 and the channel 120 are made directly by separate depths of indentations in the inner wall element 116, with the cavity 118 being made substantially in the centre of the capsule.

The inner wall element 116 also includes the injection assembly 112 which is formed by an injection nozzle 112a. Preferably and as shown, the injection nozzle 112a is solid with the inner wall element 116 and comes from a single piece with the latter. The injection nozzle 112a includes an injection orifice 112b arranged and oriented identically to the injection orifice 42a of the punching and injection element 42 described in conjunction with Figures 1 to 4.

According to a variant embodiment not represented in the capsule of the invention, the injection nozzle may also include second injection means whose injection axis extends significantly horizontally to produce a second divergent jet in the form of a thin liquid layer.

The method according to the invention for preparing a drink by injecting a liquid through a capsule containing a soluble food substance is now described in connection with the first method of manufacture of the device according to the invention illustrated in Figures 1 and 2. First, the capsule 2 is placed in the capsule port 28 while the device is in the open position (Figure 1).The perforation and injection elements 42 then simultaneously perforate the opening 12 in this configuration, in which the injection orifice 42a is placed in the capsule 2 preferably a few millimetres below the opening, and the liquid for the preparation of the beverage, e.g. hot water, is then injected under pressure into the capsule through the opening 42a in an orientation which first causes a gradual dissolution of the substance to be dissolved in a direction which passes away from the centre of the capsule 2 and which is further inclined towards a wall of the capsule, thus opening a tunnel to the said wall of the capsule 2.Once this wall is reached, and given the orientation of the jet and its kinetic energy, the jet is deflected and continues to dissolve the substance in another direction until it is deflected again against another wall, causing a swirling motion of the injected liquid around the centre of the capsule. This swirling motion therefore causes a mixing of the liquid with the said substance and allows an efficient dissolution of the substance. Simultaneously, the pressure inside the capsule increases slowly and gradually expands the membrane around the relief elements of the disc 20 in the example shown in Figures 1 and 2.Once the membrane rupture stress 16 is reached under pressure, the membrane ruptures and the dissolved liquid can escape through the flow orifice 24 of the capsule 2. The swirling jet then continues its multiple reflections to reach the remaining mass of substance until it is completely dissolved.

In the case of preparing a drink by injection of a liquid through a capsule containing a food substance to be extracted in conjunction with the second embodiment of the device according to the invention shown in Figures 6 and 7, the process according to the invention differs from that described above in that the device is initially switched into the wetting mode corresponding to the substance contained in the capsule in the case in question in the second wetting mode shown in Figure 7. In this wetting mode, an additional injection of liquid is made into the upper part of the capsule in the form of one or several layers of liquid to extract the liquid from the upper injection medium.

It should be noted that with the capsule 100 shown in Figure 10, a device with a conventional punching and injection element can be used to implement the preparation process according to the invention, since it is sufficient that the position of the cavity 118 be provided to be aligned with the punching and injection element of the device when the capsule 100 is arranged in the device so that at the time of punching the operculum 110, the punching and injection element enters the cavity 118.

Preferably the rate of liquid injection into the capsule is between 1,5 and 5 m/s in the embodiments described above.

The invention is of course not limited to the methods of execution described above and it will be understood that various modifications and/or improvements obvious to the professional can be made to them without going beyond the scope of the invention defined by the attached claims. In particular, as a variant, it may be considered to perform the perforation no longer through the operculum 12, but through other walls of the capsule, for example through the side walls when the perforating element is arranged and oriented so that the jet of liquid injected causes a swirling movement around the centre of the capsule and allows a mixing of the liquid with the substance contained in the capsule.

Abbreviations

EVOH:Copolymer of ethylene and vinyl alcoholPVDC:Polyvinyl chloride PP:Polypropylene PE:Polyethylene PA:Polyamide

Claims (33)

1. Method for preparing a beverage by injecting a liquid into an enclosure (2) containing an alimentary substance (4) which is soluble and/or to be extracted, in which the liquid is injected from at least one injection point (42), characterised in that the enclosure (2) has a central axis (A-A) into which the liquid is injected at a distance from the central axis of the enclosure (2), said injected liquid being in the form of a jet (7), which is directed away from said central axis at a non-zero angle (α) in a plane which is transverse to the enclosure and normal to said central axis, in such a way as to create a swirling movement around the centre (C) of the enclosure, thus causing said liquid to mix with said substance.
2. Method according to claim 1, wherein the enclosure (2) has a substantially vertical central axis (A-A) and wherein said jet (7) is also inclined at a non-zero angle (α) relative to the central axis of the enclosure, passing through said central axis.
3. Method according to either claim 1 or claim 2, wherein the direction of the jet from the injection point forms an angle (α) of between 20° and 60°, and preferably between 35° and 45°, with a line connecting the injection point to the central axis of the enclosure in the plane which is transverse to the enclosure and normal to said central axis.
4. Method according to claim 2, wherein the direction of the jet (7) forms an angle (β) of between 50° and 70°, and preferably between 55° and 65°, with the central axis of the enclosure (2) in the plane which is transverse to the enclosure and normal to said central axis (A-A).
5. Method according to any one of claims 1 to 4, wherein the liquid is injected from a plurality of injection points (42) which are evenly spaced apart within the enclosure (2).
6. Method according to any one of the preceding claims, characterised in that the enclosure (2) is a capsule.
7. Method according to claim 6, wherein the capsule (2) comprises an upper wall (12) and a lower wall (8), connected to one another by a lateral wall (6), and wherein the injection of the liquid takes place in the vicinity of one of the walls of the capsule and in the interior thereof.
8. Method according to claim 7, wherein the injection takes place through the upper wall (12) of the capsule.
9. Method according to claim 8, wherein the injection point (42) is located at a distance of about 2 to 5 mm from the upper wall (12).
10. Method according to any one of claims 6 to 9, wherein an additional injection of liquid is selectively performed in the upper part of the capsule in the form of one or more thin sheets of liquid, in order to wet from above the alimentary substance contained in the capsule (2).
11. Method according to any one of claims 1 to 5, wherein the enclosure is a mixing bowl which is part of a device for preparing beverages.
12. Assembly, comprising a set of disposable capsules (2) containing an alimentary substance (4) to be dissolved or extracted and a device (1) for preparing a beverage by injecting a liquid through a capsule (2) containing an alimentary substance to be dissolved or extracted, said device (1) comprising means (28) for supporting said capsule (2) and at least one liquid-injection assembly (26) for injecting the liquid in the form of a jet (7) from at least one injection point (42) into the interior of the capsule (2), characterised in that the capsule (2) has a central axis (A-A), in that the injection point (42) is at a distance from the central axis and in that said jet is directed away from said central axis at a non-zero angle (α) in a plane which is transverse to the enclosure and normal to said central axis, in such a way as to create a swirling movement in said capsule (2), thus causing said liquid to mix with said substance.
13. Assembly according to claim 12, wherein the injection assembly (26) comprises at least one perforation and injection element (42).
14. Assembly according to claim 13, characterised in that the axis of the first injection opening from the first injection point forms an angle (α) of between 20° and 60°, and preferably between 35° and 45°, with a line connecting the injection point (42) to the central axis of the capsule (2) in the transverse plane which is normal to said central axis.
15. Assembly according to either claim 12 or claim 13, wherein the capsule (2) has a substantially vertical central axis and wherein the axis of the first injection opening (42) also extends downwards.
16. Assembly according to any one of claims 13 to 15, characterised in that the axis of the first injection opening forms an angle (β) of between 50° and 70°, and preferably between 55° and 65°, with the central axis of the capsule in the transverse plane normal to said central axis.
17. Assembly according to any one of claims 12 to 16, characterised in that it comprises a plurality of perforation and injection elements (42) evenly spaced apart within the capsule.
18. Assembly according to any one of claims 12 to 17, characterised in that the perforation and injection element (42) is selected from the group consisting of a point, a blade, a knife, a needle or the like.
19. Assembly according to claim 18, characterised in that the perforation and injection element (42) is a needle with a bevel in a distal region thereof and in that the injection point is opposite said bevel.
20. Assembly according to either claim 18 or claim 19, characterised in that the perforation and injection element (42) further comprises at least one second injection opening (64), of which the axis extends substantially horizontally, to produce a second diverging jet stream in the form of a thin sheet of liquid.
21. Assembly according to either claim 18 or claim 19, characterised in that the perforation and injection element (42) comprises a plurality of second ports (64) distributed along the perimeter of said perforation element to produce a plurality of jets, which combine to form a thin sheet of liquid.
22. Assembly according to either claim 20 or claim 21, characterised in that the axis of the second injection opening(s) (64) forms an angle of between 0° and 25° with the transverse plane which is normal to the centre axis, in that the thin sheet of liquid extends in a substantially continuous manner over an angular sector of about 160°, and in that the thin sheet of liquid has a thickness less than or equal to 0.5 mm.
23. Assembly according to any one of claims 20 to 22, characterised in that it further comprises means which, in response to control elements, allow the close of the second injection opening(s) (64) for switching the device between at least two different substancewetting modes.
24. Capsule (100) containing an alimentary substance (4) which is soluble and/or to be extracted, for preparing a beverage by injecting a liquid under pressure, comprising an upper wall (110) and a lower wall (8), connected by a lateral wall (6) to define a chamber wherein the substance (4) is contained, characterised in that the upper wall (110) comprises an injection assembly (112) configured to inject said liquid in the form of a jet (7) into the chamber from at least one injection point, the injection point being at a distance from the central axis of the capsule (100), and in that and the jet (7) is directed away from said central axis at a non-zero angle in a plane which is transverse to the capsule and normal to said central axis, in such a way as to create a swirling movement in said capsule (100), thus causing said liquid to mix with said substance.
25. Capsule (100) according to claim 24, characterised in that the upper wall (110) comprises an outer wall element (114) and an inner wall element (116), together delimiting a cavity (118), which is sealed against the outside and is constructed so as to receive a perforation and injection element, and a channel (120) connecting said cavity to the injection assembly.
26. Capsule (100) according to claim 24, characterised in that the injection assembly (112) comprises a nozzle (112a) which is formed in one piece with the inner wall element (116).
27. Capsule (100) according to claim 24, characterised in that the cavity (118) and the channel (120) are formed in the inner wall element (116).
28. Capsule (100) according to any one of claims 24 to 27, characterised in that the outer wall element (114) is formed by a perforable membrane.
29. Capsule according to any one of claims 26 to 28, in which the nozzle (112a) comprises a first injection opening (112b), characterised in that the injection opening is positioned at a distance from the central axis of the capsule and in that the axis of said first injection opening (112b) extends in a direction extending at a distance from said central axis.
30. Capsule (100) according to any one of claims 24 to 29, in which the capsule has a substantially vertical central axis, characterised in that the axis of said first injection opening (112b) also extends downwards.
31. Capsule (100) according to claim 26, characterised in that the nozzle (112a) further comprises at least one second injection opening, of which the axis extends substantially horizontally to produce a second diverging jet in the form of a thin sheet of liquid.
32. Capsule (100) according to claim 26, characterised in that the nozzle (112a) comprises a plurality of second ports, distributed along the perimeter thereof, for producing a plurality of jets, which combine to form a thin sheet of liquid.
33. Capsule according to any one of claims 24 to 32, characterised in that the chamber comprises at least one rotation generator or lobeless generator about the central axis, defining a lateral wall which is cylindrical, in the shape of a frustum and/or curved.