Process of brewing tea leaves contained in a capsule

Abstract

The invention concerns a process for the preparation of a beverage in a beverage machine with a capsule comprising an enclosure containing tea leaves comprising the steps of: a) introducing water in the capsule to submerge the tea leaves in the capsule enclosure, then b) letting the tea leaves soak, then c) introducing water in the capsule until the required volume of beverage is delivered, wherein water is continuously introduced in the capsule from the beginning of step a) until the end of step b).

Claims

1. A process for the preparation of a beverage in a beverage machine using a capsule comprising tea leaves, the process comprising: a) introducing hot water delivered from a pumping and heating member in the capsule to submerge the tea leaves in the capsule enclosure; b) letting the tea leaves soak; c) introducing hot water into the capsule until the required volume of beverage is delivered; and continuously delivering water from the pumping and heating members during the three steps and continuously introduced in the capsule from the beginning of step a) until the end of step c) wherein the capsule comprises a filtering wall defining at least one filtering side of the enclosure, and an overflow wall that is located in the path of the brewed liquid after a filtering wall and comprises at least one overflow aperture, wherein the filtering wall extends from below a median horizontal plane passing through the enclosure when the capsule is positioned so that the overflow aperture is located above the plane.

2. The process of claim 1, wherein during step b) the hot water is delivered from the pumping and heating member at a soaking flow of at least 20 ml/min.

3. The process of claim 2, wherein during step b) the water is delivered from the pumping and heating member at a soaking flow between 20 and 80 ml/min.

4. The process of claim 1, wherein the quantity of water introduced during step a) is less than the internal volume of the capsule.

5. The process of claim 1, wherein water is introduced at a temperature of between 30 and 95° C.

6. The process of claim 1, wherein step b) is performed for a time period that is 5 seconds to 50 seconds.

7. A process for the preparation of a beverage in a beverage machine using a capsule comprising tea leaves, the process comprising: a) introducing hot water delivered from a pumping and heating member in the capsule to submerge the tea leaves in the capsule enclosure; b) letting the tea leaves soak; c) introducing hot water into the capsule until the required volume of beverage is delivered; and continuously delivering water from the pumping and heating member during the three steps and at least partially sent to waste during step b).

8. The process according to claim 7, wherein during step b) the hot water is delivered from the pumping and heating member at a soaking flow of at least 20 ml/min.

9. The process according to claim 8, wherein during step b) the water is delivered from the pumping and heating member at a soaking flow between 20and 80 ml/min.

10. The process of claim 7, wherein the quantity of water introduced during step a) is less than the internal volume of the capsule.

11. The process of claim 7, wherein water is introduced at a temperature of between 30 and 95° C.

12. The process of claim 7 using a capsule comprising: an enclosure containing tea leaves, a filtering wall defining at least one filtering side of the enclosure, and an overflow wall that is located in a path of the brewed liquid after a filtering wall and comprises at least one overflow aperture.

13. The process of claim 12, wherein the filtering wall extends from below a median horizontal plane passing through the enclosure when the capsule is positioned so that the overflow aperture is located above the plane.

14. The process of claim7, wherein step b) is performed for a time period that is 5 seconds to 50 seconds.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The characteristics and advantages of the invention will be better understood in relation to the figures which follow:

(2) FIG. 1 is a diagram presenting the hot water flow introduced in the capsule according to each step of the brewing process according to the preferred mode of the invention;

(3) FIG. 2 is a diagram presenting the hot water flow introduced in the capsule according to each step of the brewing process according to the less preferred of the invention;

(4) FIG. 3 is a schematic illustration of a capsule brewing system before brewing;

(5) FIG. 4 is a schematic illustration of the capsule brewing system of FIG. 3 during brewing of the capsule.

DETAILED DESCRIPTION OF THE DRAWINGS

(6) FIG. 1 illustrates the values of the hot water flows introduced in a capsule for each step of the process and the time length of introduction of these different flows according to the invention.

(7) As illustrated in FIG. 1, in step a), the capsule is filled with hot water with a flow of water of 150 ml/min. The volume of water that is introduced in the capsule corresponds to the capsule teal leaves enclosure volume.

(8) In step b): the capsule is first filled with hot water again but at a lowest flow of 50 ml/min so as to not stir the tea leaves and let the leaves unfold, then capsule is filled with hot water at a greater flow of 150 ml/min (step b′) during a short time of 3 seconds to stir the leaves in order to redistribute them, then capsule is finally filled with hot water again but at the lowest flow of 50 ml/min so as to not stir the tea leaves an let the redistributed leaves unfold.

(9) During step b), when the volume of injected water overlaps the capsule tea leaves enclosure volume, water gently drips through the capsule outlet inside a final cup or container.

(10) In step c), the capsule is filled with hot water firstly at a flow of 150 ml/min and then rapidly at a flow of 225 ml/min until the total desired volume of tea beverage flows through the capsule outlet and fills the cup.

(11) The process of preparation and dispensing of the tea beverage ready to be drunk lasts 51 seconds.

(12) FIG. 2 illustrates the values of the hot water flows introduced in the capsule for each step of the process and the time length of introduction of these different flows according to a second embodiment of the invention.

(13) In step a), the capsule is filled with hot water with a flow of water of 150 ml/min. The volume of water that is introduced in the capsule corresponds to the capsule volume.

(14) In step b): no hot water is introduced in the capsule so that the tea leaves can stay at rest and unfold. Yet, the pump is not stopped during this short period to avoid the stagnation of water in the pump and the development of scale; hot water flow is just derived from capsule inlet and sent to waste. then capsule is filled with hot water at a flow of 150 ml/min (step b′) during 3 seconds to stir the leaves and redistribute them, then the flow of hot water is derivated to waste so that no flow enters the capsule and that the redistributed leaves can stay at rest and unfold.

(15) In step c), the capsule is filled with hot water firstly at a flow of 150 ml/min and then rapidly at a flow of 225 ml/min until the total desired volume of tea beverage flows through the capsule and fills the cup.

(16) The process of preparation and dispensing of the tea beverage ready to be drunk lasts only 51 sec.

(17) FIGS. 3 and 4 illustrate a capsule system of which construction is particularly adapted for the implementation of the process of the present invention.

(18) A capsule system 1 is provided that comprises a capsule 2 and a beverage brewing device 10. For simplicity, the beverage brewing device is only schematically depicted and may, in reality, comprise additional technical features within the normal knowledge of the person skilled in the art. The capsule comprises an enclosure 20 containing beverage ingredients such as leaf tea and the like. The enclosure is demarcated by a cup-shaped housing 21 and a filtering wall 22 that is fixedly attached to peripheral inner step 23 of the housing 21. The enclosure is preferably impermeable to gas and light. The housing may encompass different cross sections such as a circular, ellipsoid, square, rectangular or polygonal section that determine as a matter of fact the general profile of the filtering wall 22. The enclosure is sized to accommodate a dose of leaf beverage ingredient of typically about between 1 to 10 grams, preferably 2 to 5 grams. The dose of leaf ingredient may depend on the final volume of beverage to produce. For an individual cup of tea, a typical dose can be of about 2 grams whereas for a tea pot, a typical dose can be of about 8 to 10 grams. As clearly apparent in FIG. 3, the capsule is positioned relative to the brewing device so that the filtering wall 22 extends substantially vertical and from substantially the bottom of the enclosure. For this, the capsule is preferably positioned in a “vertical” arrangement in the brewing device 1. The cup-shaped housing 21 can be so oriented with its large opening and its bottom oriented in a vertical position.

(19) Importantly, the capsule comprises an overflow wall 3 with an overflow aperture 25 placed at least above the median horizontal plane P of the enclosure. The filtering wall 22 and the overflow wall 3 are spaced apart a short distance sufficient to create an interstitial space “s” that is supposed, without being bound by theory, to work as a sort of “siphon” that can promote the upward motion of the denser beverage portion that is predominantly localized in the bottom of the enclosure.

(20) Both the sealing wall and the housing can be made of oxygen barrier materials and the enclosure can be substantially free of oxygen so that the freshness of the beverage ingredients can be preserved during an extended period of time. The sealing wall can be a flexible membrane or a semi-rigid plastic part. A puncturable sealing membrane is preferred such as a monolayer or a multi-layer membrane, typically, laminates of PET/Aluminium/PP, PE/EVOH/PP, PET/Metallised/PP, aluminum/PP. The enclosure is preferably oxygen free and may contain flushed inert gas such as N.sub.2, N.sub.2O or CO.sub.2.

(21) The capsule can further comprise a cover 4 that is also attached to the rim 24 of the housing 21 and overlaps the sealing wall 3. The cover forms an internal channel 40. An identification member 51 can be present on the cover (or even under the cover). This identification member contains information about the brewing parameters to be implemented to get the better brewing for the tea leaves present inside the capsule.

(22) The shape of the housing of the capsule is not very critical. Preference is given to a trunconical, ellipsoidal or hemispherical shapes for different reasons. This allows a larger surface for the exit of the beverage through the sealing wall when perforated and a reduction of the inside pressure. The housing can also be manufactured industrially at lower cost by plastic thermoforming or aluminium deep drawing. This shape with smoother corners also favours the removal of the handling members and so ejection of the capsule.

(23) Turning to the brewing device 10, it comprises capsule handling members 30, 31 that are configured to hold the capsule in the “vertical” arrangement as defined. These handling members 30, 31 can be machine jaws or any suitable mechanical enclosing means that can open and close about the capsule and can maintain it firmly in place. There is no need for providing high closing forces since the involved fluid pressure in the capsule remains relatively low and, preferably, as close as possible to the atmospheric pressure. Also, since the capsule can withstand the low brewing pressure therefore the capsule does not necessarily need to be entirely enclosed but simply held water tightly in place during brewing. This participates to a simplification of the machine and it reduces machine costs.

(24) The brewing device comprises a water supply 32, such as a water tank, a water pump 33, a heater 34 and a hot water injection line 35 that is managed through the handling member 30. The brewing device may also comprise a controller 39 and a user interface board (not shown) to manage the beverage preparation cycles as known in the art. A backpressure valve 36 can be provided to lower the pressure at the entry side of injection member 38 such as a needle(s) or blade(s) creating a water inlet in the capsule. Of course, the backpressure valve could be omitted and a low pressure pump could be used that delivers fluid at low pressure. Medium to high pressure pump may however be preferred because of their robustness and reliability and so used in combination with a backpressure valve.

(25) The brewing device may further comprise a means 37 for perforating the cover 4 and creating a beverage outlet. As shown in FIG. 3, the perforating means 37 can be activated after closing of the handling members 30, 31 about the capsule. The perforating means is forced or guided through the cover 4. The perforator can be driven by a solenoid or any other equivalent drive means or even manually.

(26) The brewing device may further comprise a detection unit 50 to convert the information of the identification member 51 of the capsule into brewing instructions through the controller 39. In the present the invention, the information especially varies according to the tea leaves present inside the capsule. The information provide to the control unit 39 instructions so that the steps a), b) and c) of the process of the present invention is implemented with specific features adapted for each type of tea leaves that are: the values of water flow of steps a), b) and c), the number of stirring periods in step b), the time length of the different steps.

(27) Preferably the information can be read from the capsule 1 in a non-optical manner, as the optical reading e.g. using a bar code has the disadvantages of having a negative impact on the aesthetic impression of the outer appearance of the capsule and of being prone to failure due to the legibility of the bar code in the environment of the beverage production process. Preferably the information is coded in a digital manner. The information can be coded by a modulation of the surface structure of a face of the capsule 1. E.g. a hole or a recession can represent one logical sate (e.g. “0”), while another surface state (“no recession” or “no hole”) can represent the other logical state (e.g. “1”). Replacing the bar code by a surface modulation which can then be detected in a non-optical manner (or even in an optical manner) enhances the reliability of the information reading from the capsule.

(28) In relation to FIG. 4, the method of the invention works as follows. A capsule is inserted in the brewing device and the capsule handling members 30, 31 are closed about the capsule to position it with the sealing wall being substantially vertically oriented. An outlet aperture is created by the perforating means 37 that punctures the cover 4 and is withdrawn to leave the aperture opened. On the opposite side of the capsule, the fluid injection member 38 is introduced in the capsule's enclosure. Hot water is thus injected in the capsule at relatively low pressure, preferably, at a pressure not exceeding 0.2 bar. Hot water slowly fills the capsule in and submerges the beverage ingredients in the enclosure. The brewed beverage is filtered through the filtering wall 22. A denser portion 5 of the beverage may tend to settle in the bottom of the enclosure; which portion is also filtered through the filtering wall since it is properly placed adjacent this portion. The denser beverage is evacuated through the interstitial space “s” as caused by the variation of pressure between the lower part of the space and the upper part of said space therefore acting similarly to a “siphon”. The rest of the beverage is also filtered also by passing through the filtering wall at different vertical levels up to the upper level of the fluid in the enclosure and is evacuated to the overflow aperture 25.

(29) It should be noted that the overflow aperture should preferably be placed above the ¾ of the total height of the enclosure and even preferably be placed above the ⅘ of the total height of the enclosure; thus ensuring a more complete submergence of the beverage ingredients and a slower evacuation of the beverage from the enclosure which favours a better infusion process.

(30) The “total height” of the enclosure is meant to be the total distance separating the lowermost point of the enclosure to the uppermost point of the enclosure when the capsule is positioned in the beverage machine ready for the brewing operation. In a possible mode, the filtering wall can be substantially equal to the total height of the enclosure.

(31) The principle of the brewing method according to FIGS. 3 and 4 encompasses different variants and equivalences.

(32) For instance, the overflow wall 3 may not be perforated but may be pre-opened by a pre-cut overflow aperture. The pre-cut overflow aperture means an aperture which has already been made at the manufacturing stage of the capsule. Freshness of the beverage ingredients may so be preserved by different means such as by an airtight closed cover with a sealed outlet that is unsealed just before brewing or by the use of an airtight overwrap package that encloses the capsule.

(33) The capsule may also be conceived without the cover 4 and its channelling function. In which case, the front handling member 31 may be designed to collect the brewed liquid as it passes the overflow wall 3 and travels down to the recipient.