Patent Publication Number: US-2018044104-A1

Title: System for producing a tea beverage

Description:
The present invention relates to a system for producing a tea beverage, comprising a brewing chamber and a portion capsule having a cavity in which tea granules are contained, wherein the portion capsule is provided in the brewing chamber and a liquid flows through the brewing chamber and the portion capsule and, in the process, extracts and/or desorbs the tea granules and as a result produces a tea beverage. 
     Systems of this kind are known from the prior art and are used, for example, to produce so-called fruit teas. To this end, dried pieces of fruit, dried fruit skin and/or herbs are provided in the portion capsule. However, the systems known from the prior art have the disadvantage that the portion capsules often become blocked or even crack when the tea beverage is brewed. 
     The object of the present invention was therefore to provide a system which does not exhibit the disadvantages of the prior art. 
     This object is achieved by a system for producing a tea beverage comprising a brewing chamber and a portion capsule having a cavity in which tea granules are contained, wherein the portion capsule is provided in the brewing chamber and a liquid flows through the brewing chamber and the portion capsule and, in the process, extracts and/or desorbs the tea granules and as a result produces a tea beverage, wherein the tea granules are provided such that the square of the average volumetric flow rate of the liquid is at least 1.3. 
     According to the invention, the system comprises a brewing chamber and a portion capsule. 
     The portion capsules for producing a tea beverage are preferably in the shape of a truncated cone or cylinder and are produced, for example, from a thermoformed plastic film or using a plastic injection-moulding process. Said portion capsules usually have a capsule base, a cavity with an open filling side, and a collar edge on which a cover film or foil is sealed or adhesively bonded. Before the cover film or foil is arranged on the collar edge, the existing cavity is filled with tea granules. A filter element which is supported against the capsule base is preferably arranged between the tea granules and the capsule base, the said filter element preventing particles from entering the tea beverage. The tea granules are, in particular, substances which are used for producing a fruit and/or herbal tea, that is to say preferably dried pieces of fruit flesh and/or fruit skin and/or tea-like substances which can each be contained in whole form and/or in comminuted, in particular ground, form. The granules often have a large number of different components which are contained, in particular, as a mixture. For example, the granules include fine cuts of fruit, in particular apple and/or orange, flesh and/or skin which can be contained in ground or unground form. Lemongrass, ginger and any other substance from which a fruit tea can be produced is also a preferred constituent part of the tea granules. 
     Before the extraction process, the portion capsule is preferably sealed off from the environment in a substantially aroma-tight manner. However, the portion capsule does not have to be hermetically sealed, but rather can also be provided in a hermetically sealed package before it is used, the said hermetically sealed package then being, for example, manually opened, and/or openings which may be present in the capsule base and/or in the cover region are covered by a film or foil which is pulled off and/or pierced before the tea is produced. 
     The brewing chamber, which is part of a corresponding automatic machine, comprises, for example, two parts which can be separated and joined together, and therefore open and, respectively, close the brewing chamber. The portion capsule is inserted into the brewing chamber in order to prepare the tea beverage. After or during the closing process of the brewing chamber, the capsule is preferably opened on its closed bottom side by means of an opening mandrel which is arranged in the brewing chamber, and after the brewing chamber is sealed off, the filling side of the portion capsule, which filling side is sealed by means of a sealing film or foil, is tapped by means of one or more puncturing means. Hot water is then delivered to the portion capsule under pressure. The water flows through the tea granules and extracts and/or dissolves the substances which are required for producing the beverage from the tea granules. The tea beverage which is produced in this way leaves the portion capsule and is collected in a container. The temperature of the hot water is preferably 90-100° C. The hot water is preferably provided at the portion capsule input at a pressure of 10-20 bar. The volumetric flow rate of the hot water is preferably continuous, but can also be intermittent. 
     According to the invention, the tea granules are now provided such that the square of the average volumetric flow rate is at least 1.3. In this case, the average volumetric flow rate is the achieved yield of tea beverage, measured in millimetres, divided by the time required for producing the beverage, measured in seconds. It has now surprisingly been found that if is ensured that the portion capsule does not become blocked and/or crack during tea production only if this lower limit is complied with. This average volumetric flow rate is influenced, for example, by the swelling index of the tea granules, the weighed portion, the volume of the cavity and/or the particle size distribution, Dv50. 
     The Dv50 of the tea granules is preferably 300-1000, preferably 350-900 μm. 
     According to a preferred embodiment of the present invention, the swelling index of the tea granules is 1.8-4.0, preferably 2.0-3.8. The swelling index is determined by a specific quantity of tea granules being presented and then a multiple of the volume of the tea granules of water at a temperature of 100° being added to the said tea granules. The volume of the tea granules is determined before and after the water is added and a quotient which gives the swelling index is formed from said measurements. Since tea granules always swell when water is added, the quotient is always greater than 1. 
     The weighed portion of granules is preferably 0.4-7, preferably 0.5-5 g per portion capsule. This quantity has proven expedient for producing 150-250 ml of tea beverage, preferably 180-220 ml. 
     The volume of the cavity is preferably 20-30 ml, particularly preferably 22-26 ml, very particularly preferably 23.5-24.5 ml. 
     A filter element is preferably provided in the cavity, the said filter element preferably having a felt structure. The filter element prevents particles entering the finished beverage. The felt structure particularly preferably has a mass per unit area of between 600 and 1500 grams per square metre, particularly preferably between 1000 and 1400 grams per square metre, and very particularly preferably of 1200-1300 grams per square metre. The thickness of the filter element is preferably between 0.8 and 3.3 millimetres, particularly preferably between 1.1 and 3.0 millimetres, and is very particularly preferably 1.2-1.4 millimetres. The felt structure is, in particular, a needle felt structure. The filter element preferably comprises at least a felt structure and a support structure, in particular a woven fabric structure, wherein the felt structure particularly preferably comprises at least a partial section of the volume of the support structure. The felt structure preferably extends over the entire cross section of the support structure, but particularly preferably only over a subregion of the height of the support structure. The felt structure is preferably connected to the support structure in an interlocking, force-fitting and/or cohesive manner. The filter element preferably has two or more felt structures which are preferably separated from one another by the support structure. The thickness of the two felt structures can be the same or different. A felt structure which faces the tea granules is preferably thinner than the felt structure which faces the capsule base, or vice versa. The surface of the felt structure is preferably treated, in particular heat-treated, in order to fix loose fibres for example. The filter element which has a felt structure is preferably inserted only into the capsule, in particular onto the base of the said capsule. However, the filter element can also be connected to the capsule, in particular to the base of the said capsule, in particular in a cohesive manner. When the portion capsule is perforated, the perforation means can enter this filter element. A plurality of filter elements, which have one or more felt structures and a support structure, are preferably arranged one above the other in the capsule, and possibly connected to one another. The filter element which has the felt structure is produced, for example, by a woven fabric structure comprising longitudinal and transverse threads being provided. In order to construct a felt, in particular a needle felt, fibre units of from 0.8 to 7 dtex are preferably selected. The combination of the individual fibres with one another to form a felt and/or anchoring of the said felt in the support structure preferably takes place by the production process of needling. In this case, needles having reverse barbs are stabbed into the presented fibre package at high speed and pulled out again. Owing to the barbs, the fibres are intertwined with one another and/or with the supporting woven fabric by means of a large number of loops which form. 
     According to a preferred embodiment, the capsule base has a prefabricated output opening which is preferably sealed off using a film or foil, wherein the film or foil particularly preferably has a pull-off tab for pulling off the film or foil by hand. However, the film or foil can also be perforated by a perforation means in the brewing chamber. The output opening preferably has a cross-sectional area of such a size that no appreciable pressure loss occurs as the finished beverage flows out at the output opening, even if there is a perforation means in the output opening. The tea beverage is preferably under substantially no pressure downstream of the filter element, that is to say it is at ambient pressure. The outlet opening preferably has a diameter of between 10 and 14 mm. 
     The filter element preferably spans the output opening. 
    
    
     
       Exemplary embodiments of the invention are illustrated in the figures and explained in greater detail in the following description. The figures are described only by way of example and do not restrict the general concept of the invention. 
         FIG. 1  shows a longitudinal section through a portion capsule according to a first embodiment of the present invention, which portion capsule is designed for preparing tea. 
         FIG. 2  shows a longitudinal section through a portion capsule which is situated in a closed brewing chamber, according to the first embodiment of the present invention. 
         FIG. 3  shows a longitudinal section through a portion capsule, which is situated in a closed brewing chamber, according to a second embodiment of the present invention. 
         FIG. 4  shows a schematic sectional view through a portion capsule having a prefabricated opening, in the capsule base region in this case. 
     
    
    
     Identical parts are always provided with the same reference symbols in the various figures and will therefore also generally each be cited or mentioned only once. 
       FIG. 1  shows one embodiment or the portion capsule  1  according to the invention. The portion capsule  1  comprises a capsule body  2  which is in the form of a truncated cone and has a closed capsule base  3  and has a collar edge  5  which is arranged on its filling side  4 , a cover film or foil  6  being welded or adhesively bonded to the said collar edge. Therefore, a cavity  100 , which is preferably sealed in an air- and aroma-tight manner and which contains a pulverulent or granular or leaf-like beverage substance  101 , is formed between the capsule base  3  and the cover film or foil  6 . In the present case, the beverage substance  101  comprises substances for producing a fruit tea, which substances can be present in whole form and/or in comminuted form, in particular as fine cuts. A filter element  7 , in this case having a felt structure, is arranged on the inner side  3   a  of the closed capsule body base  3 , that is to say within the cavity  100 . The filter element  7  lies either loosely on the inner side  3   a  of the capsule base  3  or is connected to the inner side  3   a  of the capsule body base  3  in a fixed, that is to say preferably cohesive, manner. In the second variant, the filter element  7  is attached in a cohesive manner to the capsule base  3  along a ring, in particular only in an edge region  3 ′ of the capsule base  3 . 
       FIG. 2  shows a portion capsule  1  according to the embodiment of the present invention illustrated in  FIG. 1 , wherein the portion capsule  1  is arranged in a closed brewing chamber  8  in  FIG. 2 . The brewing chamber  8  comprises a first brewing chamber element  9  and a second brewing chamber element  10 , wherein the first brewing chamber element  9  is provided for the insertion of the portion capsule  1  such that it can move in relation to the second brewing chamber element  10 , or vice versa. A seal  11  is arranged between the two brewing chamber elements  9 ,  10 . The first brewing chamber element  9  substantially comprises a closing piston  12  with puncturing elements  13   a,    13   b  for opening the cover film or foil  6  of the portion capsule  1 , a preparation liquid supply means  14  and the seal  11 . The second brewing chamber element  10  substantially comprises a brewing chamber bell  15 , which partially surrounds the portion capsule  1  and has a opening mandrel  16  which is arranged on the base of the brewing chamber bell  15  and is provided with outlet grooves  17  in this case, and a beverage discharge  18 . For the purpose of accommodating the portion capsule  1 , the brewing chamber  8  is in an open state, not illustrated, in which the first and the second brewing chamber element  9 ,  10  are spaced apart from one another, in order to ensure supply of the portion capsule  1 , and in the illustrated closed state, in which a preparation process for producing a beverage using the portion capsule  1  can be carried out. In the closed state, the brewing chamber  8  is sealed off in a sealed manner. When and/or after the brewing chamber  8  is moved from the open state to the depicted closed state, the cover film or foil  6  is pierced by the puncturing elements  13   a,    13   b , with the result that preparation liquid, in particular hot brewing water, passes through the preparation liquid supply means  14  under pressure and into the cavity  100  in the portion capsule  1 . Furthermore, the capsule base  3  is perforated here by the perforation means, which is in the form of an opening mandrel  16 , when the brewing chamber  8  is closed, with the result that an output opening  107  is produced in the portion capsule  1 , it being possible for the produced tea to leave the portion capsule  1  in the direction of the beverage discharge means  18  through the said output opening. In order to assist delivery of the beverage liquid, the opening mandrel  16  can have the outlet grooves  17  on its casing surface. In the illustration, the base  3  of the portion capsule  1  which is located in the brewing chamber  9 ,  10  is pierced by the opening mandrel  16  of the second brewing chamber element, and the filter element  7  which is situated above the puncturing point is slightly raised, and possibly tapped but not pierced, by the puncturing spike  19  of the opening mandrel  16 . This is achieved, in particular, by the central region  7 ″ of the felt structure not being connected to the capsule base  3  in a cohesive manner, but rather the filter element  7  being connected to the capsule base  3  in a cohesive manner only in the edge region  3 ′ of the capsule base  3 , with the result that the said filter element is raised only from the capsule base  3  as a result of the mechanical contact with the spike of the opening mandrel  16 , and therefore remains intact (that is to say is tapped, for example, by the opening mandrel  16  but is intact). The capsule base  3  and the filter element  7  remain in contact with one another, and in particular remain connected to one another in a cohesive manner, in the edge region  3 ′ of the capsule base  3  and in the edge region  7 ′ of the filter element  7 , with the result than no beverage substance  101  enters the beverage discharge means  18  from around the filter element  7 . 
       FIG. 3  shows a portion capsule  1  according to a second embodiment of the present invention, wherein the second embodiment is substantially similar to the first embodiment illustrated in  FIG. 2  and the portion capsule  1  is likewise shown in a closed brewing chamber  8 . In contrast to the first embodiment, the portion capsule base  3  has, however, a protrusion  21 , which is directed towards a recess  20  in the brewing chamber base  3   a  (the protrusion  21  is therefore directed in a direction which is opposite to the filling side  4 ) and which the opening mandrel  16  punctures, without piercing the filter element  7  in the process, in the puncturing region of the opening mandrel  16 . It is therefore not necessary for the filter element  7  to be lifted away from the capsule base  3 . In order to produce the beverage, the brewing chamber  8  is once again closed after the portion capsule  1  is inserted into the brewing chamber  8 . During the closing process, the cover film or foil  6  of the portion capsule  1  is perforated by means of the puncturing means  13   a,    13   b  and brewing water is provided via the liquid inlet  14  after the first and the second brewing chamber element  9 ,  10  are combined and sealed off (by means of the seal  11 ). The opening mandrel  16  likewise makes an opening in the base  3  of the portion capsule  1  during the closing process of the brewing chamber. The filter element  7  which is situated above the puncturing point is matched in respect of its thickness and tear resistance to the penetration depth of the puncturing spike  19  of the opening mandrel  16 , with the result that the filter element  7  is preferably not pierced. As an alternative, the filter element  7  is situated above the protrusion  21  of the capsule base  3 , which protrusion is situated in the recess in the brewing bell base  23 , and the opening mandrel  16  penetrates only the protrusion  21  of the capsule base  3  and does not reach as far as the filter element  7 . The liquid, hot water in the case of the production of tea, then flows into the capsule  1 . In the capsule, this liquid flows through the tea granules  101  and extracts and/or dissolves the substances which are required for producing the beverage from the tea granules  101 . The flow of the liquid in the cavity  100  through the tea granules  101  is illustrated by reference symbol  22 . The resulting beverage then flows through the filter element  7  which is arranged between the tea granules  101  and the on the capsule base  3 , the said filter element preventing constituent parts or the tea granules  101  from entering the resulting beverage in particulate form, and will further enter a collection vessel, for example a cup or pot, via the opening which is made by the opening mandrel  16  in the capsule base  3  and via the outlet grooves  17  in the opening mandrel  16 . 
       FIG. 4  shows a sectional view through a portion capsule  1  according to a further embodiment of the present invention. This embodiment is substantially similar to the embodiment shown in  FIG. 1 , wherein the portion capsules  1  of the present embodiment is equipped with a permanent output opening  107  in the capsule base  3 , which output opening is first sealed off by the film or foil  108 . In this case, the film or foil  108  preferably has a pull-off tab  109  for pulling off the film or foil  108  by hand. Perforation of the capsule base  3  by means of an external perforation mean  16  is not provided, but is also a feasible embodiment. Instead, when the portion capsule  1  is inserted into the brewing chamber  8 , the film or foil  108  is simply removed from the capsule base  3  by means of the pull-off tab  109 , and the brewing process can then be started directly and without perforation of the capsule base  3 . However, it is also possible for the film or foil  103  to remain on the portion capsule and be pierced by the perforation means. The filter element spans the output opening  107  which is preferably of such a size that no appreciable pressure loss from the outflowing beverage is produced at the said output opening, even when the perforation means is located in the opening. This also applies in the case of the opening mandrel being located in the output opening. 
     It is clear to a person skilled in the art that it is possible for the perforation means  16  to span, tap and/or pierce the filter element when the said perforation means penetrates the capsule, that is to say it is possible for the filter element to be connected, for example, to the base of the capsule in a cohesive manner at least in sections, to be provided so as to bear against the base as far as possible over a large surface area and/or to be spanned. 
     The invention is explained further in the text which follows with reference to the appended table. 
     In the table: 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 QZ [—] 
                 is the swelling index, ml of the wet tea 
               
               
                   
                   
                 substance/ml of the dry tea substance 
               
               
                   
                 t preparation  [s] 
                 is the time which is required in order to 
               
               
                   
                   
                 achieve the desired yield 
               
               
                   
                 Yield [ml] 
                 is the achieved, collected quantity of tea 
               
               
                   
                 Dv50 [μm] 
                 is the mean particle diameter of the tea granules 
               
               
                   
                 Q [ml/s] 
                 is the average volumetric flow rate = 
               
               
                   
                   
                 Yield/t preparation   
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                   
                   
                 Weighed 
                   
                   
                   
                   
                   
                   
               
               
                   
                   
                 portion 
                 t preparation   
                 Yield 
                 Dv50 
                 Q 
                   
                 Q 2   
               
               
                 Sample 
                 QZ 
                 [g] 
                 [s] 
                 [ml] 
                 [μm] 
                 [ml/s] 
                 Cracks 
                 [ml 2 /s 2 ] 
               
               
                   
               
               
                 Fine cuts 
                 3.63 
                 1 
                 68 
                 203 
                 886 
                 2.9853 
                 No 
                 8.9120 
               
               
                 of apple - 
               
               
                 unground 
               
               
                   
                 3.63 
                 2 
                 124 
                 192 
                 886 
                 1.5484 
                 No 
                 2.3975 
               
               
                 Fine cuts 
                 3.67 
                 0.5 
                 75 
                 196 
                 402 
                 2.6133 
                 No 
                 6.8295 
               
               
                 of apple - 
               
               
                 ground 
               
               
                   
                 3.67 
                 1 
                 125 
                 139 
                 402 
                 1.1120 
                 Yes 
                 1.2365 
               
               
                   
                 3.67 
                 2 
                 258 
                 138 
                 402 
                 0.5349 
                 Yes 
                 0.2861 
               
               
                 Lemongrass 
                 2.15 
                 2.1 
                 94 
                 191 
                 557 
                 2.0319 
                 No 
                 4.1287 
               
               
                   
                 2.15 
                 2.1 
                 124 
                 190 
                 557 
                 1.5323 
                 No 
                 2.3478 
               
               
                   
                 2.15 
                 2.1 
                 241 
                 193 
                 557 
                 0.8008 
                 Yes 
                 0.6413 
               
               
                 Lemongrass 
                 2.07 
                 2.1 
                 67 
                 204 
                 795 
                 3.0448 
                 No 
                 9.2707 
               
               
                   
                 2.07 
                 2.1 
                 69 
                 201 
                 795 
                 2.9130 
                 No 
                 8.4858 
               
               
                   
                 2.07 
                 2.1 
                 68 
                 203 
                 795 
                 2.9853 
                 No 
                 8.9120 
               
               
                   
               
            
           
         
       
     
     LIST OF REFERENCE SYMBOLS 
     
         
           1  Portion capsule 
           2  Capsule body 
           3  Capsule base 
           3   a  Inner side of the capsule base 
           3 ′ Edge region of the capsule base 
           4  Filling side 
           5  Collar edge 
           6  Cover film or foil 
           7  Filter element 
           7 ′ Edge region of the filter element 
           7 ″ Central region of the filter element 
           8  Brewing chamber 
           9  First brewing chamber element 
           10  Second brewing chamber element 
           11  Seal 
           12  Closing piston 
           13   a  Puncturing element 
           13   b  Puncturing element 
           14  Preparation liquid supply means 
           15  Brewing bell 
           16  Opening mandrel 
           17  Outlet grooves 
           18  Discharge means 
           19  Puncturing spike 
           20  Recess 
           21  Protrusion 
           22  Preparation liquid flow 
           23  Brewing bell base 
           100  Cavity 
           101  Tea granules 
           102  Side wall region 
           107  Output opening 
           108  Film or foil 
           109  Pull-off tab