Fabrication of core/shell capsules of different geometries and treatment therafter

Abstract

Multi-shelled capsules are made by co-extruding a first liquid flavorant composition and a first shell-forming polymeric material to form droplets which are hardened to form an inner shell containing a first liquid flavorant composition, and then coated with a second shell-forming polymeric material which is hardened to form an outer shell. The result is a capsule where the inner surface of the outer shell is separate and/or separable from the outer surface of the inner shell to define a space, wherein a second liquid flavorant composition may be located.

What is claimed is: 
     
         1 . A multi-shelled capsule comprising:
 (a) an inner core comprising a first liquid flavorant composition,   (b) an inner shell of a first polymeric material at least partially enclosing the inner core,   (c) an outer shell of a second polymeric material at least partially enclosing the inner shell, and   (d) a second liquid flavorant composition disposed in a space between the inner shell and the outer shell.   
     
     
         2 . The multi-shelled capsule of  claim 1 , wherein said capsule is substantially spherical and has a diameter of 1 to 7 mm. 
     
     
         3 . The multi-shelled capsule of  claim 1 , wherein the inner and outer shells have a combined thickness, including the space between the shells, of between about 12 and 43 μm. 
     
     
         4 . The multi-shelled capsule of  claim 1 , wherein the multi-shelled capsule has a burst strength of between about 6 and 11 N. 
     
     
         5 . The multi-shelled capsule of  claim 1 , wherein at least one of the inner and outer shells comprises cross-linked alginate. 
     
     
         6 . A smoking article, comprising at least one multi-shelled capsule of  claim 1 . 
     
     
         7 . The smoking article of  claim 6 , wherein the first and second liquid flavorant compositions are different. 
     
     
         8 . The smoking article of  claim 6 , wherein the at least one multi-shelled capsule comprises a plurality of multi-shelled capsules, at least some of which have different combined thicknesses of inner and outer shells. 
     
     
         9 . The smoking article of  claim 6 , wherein
 the smoking article comprises a filter, and   said at least one multi-shelled capsule is disposed in the filter, and is disposed to be crushable by a smoker to release the first and/or second liquid flavorant composition into the filter,   wherein said at least one multi-shelled capsules are substantially ovoid.   
     
     
         10 . A smokeless tobacco product, comprising at least one multi-shelled capsule of  claim 1 . 
     
     
         11 . The smokeless tobacco product of  claim 10 , wherein the at least one multi-shelled capsule comprises a plurality of multi-shelled capsules, at least some of which have different combined thicknesses of inner and outer shells. 
     
     
         12 . The multi-shelled capsule of  claim 1 , prepared by:
 (a) co-extruding a first liquid flavorant composition and a first shell-forming polymeric material to form a core-shell droplet;   (b) hardening the first shell-forming polymeric material of the droplet to form an inner shell around an inner core, the inner core comprising the first liquid flavorant composition;   (c) coating the inner shell with a coating layer comprising a second shell-forming polymeric material; and   (d) hardening the second shell-forming polymeric material by contacting the second shell-forming polymer with polyvalent metal ions present in or on the inner shell, to form an outer shell of the multi-shelled capsule.   
     
     
         13 . The multi-shelled capsule of  claim 12 , wherein an inner surface of the outer shell is separated from an outer surface of the inner shell; and a second liquid region is between an outer surface of the inner shell and an inner surface of the outer shell. 
     
     
         14 . The multi-shelled capsule of  claim 13 , wherein the second liquid region is formed by:
 (a) coating the inner shell with a gel comprising one or more components that are substantially insoluble in the second shell-forming polymeric material, whereby before or upon hardening of the second shell-forming polymeric material the second liquid region is formed and comprises the one or more components that are substantially insoluble; or   (b) before the second shell-forming polymeric material is completely hardened, contacting either the coated inner shell or the multi-shelled capsule with a second liquid flavorant composition for a time and under conditions sufficient for at least a portion of said second liquid flavorant composition to move through said outer shell or said coating layer to form said liquid region, followed by hardening of the second shell-forming polymeric material.   
     
     
         15 . The multi-shelled capsule of  claim 1 , wherein said first liquid flavorant composition comprises a first flavorant selected from the group consisting of menthol, mint, chocolate, licorice, citrus and other fruit flavors, gamma octalactone, vanillin, ethyl vanillin, cinnamon, methyl salicylate, linalool, bergamot oil, geranium oil, lemon oil, ginger oil, tobacco extract, phenylacetic acid, solanone, megastigmatrienone, 2-heptanone, benzylalcohol, cis-3-hexenyl acetate, valeric acid, valeric aldehyde, and mixtures thereof. 
     
     
         16 . The multi-shelled capsule of  claim 1 , wherein the multi-shelled capsule is substantially ovoid. 
     
     
         17 . The multi-shelled capsule of  claim 12 , wherein said first shell-forming polymeric material comprises a cross-linkable polysaccharide, a hardenable protein, or a hardenable wax. 
     
     
         18 . The multi-shelled capsule of  claim 17 , wherein said cross-linkable polysaccharide is selected from the group consisting of alginates, pectins, carrageenans, chitosans, dextrans, and combinations or mixtures thereof. 
     
     
         19 . The multi-shelled capsule of  claim 12 , wherein said hardening the second shell-forming polymeric material comprises drying in a tumbling dryer. 
     
     
         20 . The multi-shelled capsule of  claim 12 , wherein said co-extruding step comprises using a co-extruder comprising an inner nozzle diameter of between about 0.5 mm and 2 mm, and an outer nozzle diameter of between about 1.5 mm and 3 mm, wherein the inner nozzle is fed at between about 40 mbar and 80 mbar and the outer nozzle is fed at between about 100 mbar and 130 mbar.