A capsule for improved beverage quality

Abstract

The present invention is directed to a capsule ( 1 ) for use in a beverage preparation machine, said capsule comprising: (i) lateral walls ( 2 ), a pierceable injection wall ( 3 ) adapted to be pierced by fluid injection means ( 4 ) of the machine, and a dispensing wall ( 5 ) adapted to dispense said beverage, that delimit a closed internal volume, (ii) a flexible fluid distributor wall ( 7 ), that is located inside the closed volume of the capsule, at a distance below the pierceable wall ( 3 ) so as to separate:—a headspace compartment ( 8 ) between the pierceable wall ( 3 ) and said fluid distributor wall ( 7 ) which is able to accommodate the injection means during injection of the fluid, and—an ingredient compartment ( 9 ) located between said fluid distributor wall ( 7 ) and said dispensing wall ( 5 ), containing a bed of non-soluble beverage ingredient particles, characterized in that the head-space compartment ( 8 ) contains a superabsorbent polymer ( 10 ) able to absorb a quantity of the injected fluid, and swell so as to fill the headspace compartment ( 8 ) and exert a pressure force onto the surface of the fluid distributor wall ( 7 ) to prevent substantial movement of ingredient particles while said fluid traverses said ingredient.

1 . A capsule for use in a beverage preparation machine, the capsule comprising:
 lateral walls, a pierceable injection wall adapted to be pierced by a fluid injection member of the machine, and a dispensing wall adapted to dispense the beverage, that defines a closed internal volume,   a flexible fluid distributor wall, that is located inside the closed volume of the capsule, at a distance below the pierceable wall so as to separate:   a headspace compartment ( 8 ) between the pierceable wall and the fluid distributor wall which is able to accommodate the injection member during injection of the fluid, and   an ingredient compartment located between the fluid distributor wall and the dispensing wall, containing a bed of non-soluble beverage ingredient particles,   the headspace compartment contains a superabsorbent polymer able to absorb a quantity of the injected fluid, and swell so as to fill the headspace compartment and exert a pressure force onto the surface of the fluid distributor wall to prevent substantial movement of ingredient particles while the fluid traverses the ingredient.   
     
     
         2 . A capsule according to  claim 1 , wherein the fluid injection member is a hollow needle having one outlet for producing a jet of fluid. 
     
     
         3 . A capsule according to  claim 1 , wherein the fluid is water. 
     
     
         4 . A capsule according to  claim 1 , wherein the superabsorbent polymer is selected from the group consisting of a food-grade sodium polyacrylate and potassium polyacrylate. 
     
     
         5 . A capsule according to  claim 1 , wherein the superabsorbent polymer comprises particles made of:
 a low cross-linked superabsorbent particle core, which provides fast absorption, and   a high cross-linked superabsorbent coating, which provides good fluid retention properties.   
     
     
         6 . A capsule according to  claim 1 , wherein the mass of dry superabsorbent polymer in the capsule is between 0.01 g and 50 g. 
     
     
         7 . A capsule according to  claim 1 , wherein the beverage ingredient contained therein comprises roast and ground coffee powder.