Process for purifying starches

Abstract

The present invention relates to a process for purifying starches. More particularly, the invention relates to a method of removing off-flavors, off-odors, and off-colors from starches by extraction of the components causing the off-flavors, off-odors, and off-colors with a fluid in the supercritical or liquid phase.

1 . A process for extracting components from starch comprising:
 (i) contacting the starch with a supercritical fluid or liquid phase fluid for a sufficient length of time and at a sufficient temperature and pressure effective to dissolve the components in the supercritical fluid or liquid phase fluid without substantially changing the physical structure of the starch; and   (ii) removing the supercritical fluid or liquid phase fluid containing the dissolved components.   
     
     
         2 . The process of  claim 1  in which the extraction is achieved via countercurrent column method. 
     
     
         3 . The process of  claim 1  in which the extraction is achieved via the solid matrix method. 
     
     
         4 . The process of  claim 1  in which the extraction is achieved via the completely mixed vessel method. 
     
     
         5 . The process of  claim 1  in which step (i) comprises contacting the starch with the supercritical or liquid phase fluid in combination with a co-solvent. 
     
     
         6 . The process of  claim 5  in which the co-solvent is ethanol. 
     
     
         7 . The process according to any one of  claims 1  through  6  in which the extraction is conducted with a supercritical fluid or liquid fluid and the fluid is CO 2 . 
     
     
         8 . The process according to any one of  claims 1  through  6  in which the extraction is conducted with a supercritical fluid at pressures of greater than 300 bar (30.0 MPa) and temperatures of between about 80° to about 120° C. 
     
     
         9 . The process according to any one of  claims 1  through  6  in which the extraction is conducted with supercritical CO 2  at pressures of greater than 300 bar (30.0 MPa) and temperatures of between about 80° to about 120° C. 
     
     
         10 . The process according to any one of  claims 1  through  6  in which the extraction is conducted with a supercritical fluid at pressures of greater than 600 bar (60.0 MPa) and temperatures of between about 80° to about 120° C. 
     
     
         11 . The process according to any one of  claims 1  through  6  in which the extraction is conducted with supercritical CO 2  at pressures of greater than 600 bar (60.0 MPa) and temperatures of between about 80° to about 120° C. 
     
     
         12 . A purified starch produced according to the process of comprising:
 (i) contacting the starch with a supercritical fluid or liquid phase fluid for a sufficient length of time and at a sufficient temperature and pressure effective to dissolve the components in the supercritical fluid or liquid phase fluid without substantially changing the physical structure of the starch; and   (ii) removing the supercritical fluid or liquid phase fluid containing the dissolved components.   
     
     
         13 . A product comprising the starch of  claim 12 . 
     
     
         14 . The product of  claim 13  in which the product is a food. 
     
     
         15 . The product of  claim 14  in which the food is selected from the group consisting of gravies, soups, fruit preparations, dressings; food fillings; sauces; condiments; puddings; and dairy products. 
     
     
         16 . The product of  claim 15  in which the dairy product is yogurt. 
     
     
         17 . The product of  claim 12 , wherein step (1) comprises contacting the starch with the supercritical or liquid phase fluid in combination with a co-solvent. 
     
     
         18 . The product of  claim 17 , wherein the co-solvent is ethanol. 
     
     
         19 . The product of  claim 12 , wherein the extraction is conducted with a supercritical fluid and the fluid is carbon dioxide. 
     
     
         20 . The product of  claim 12 , in which the extraction is conducted with a supercritical fluid at pressures of greater than 300 bar (30.0 MPa) and temperatures of between about 80 to about 120° C. 
     
     
         21 . The product of  claim 20 , in which the supercritical fluid is carbon dioxide. 
     
     
         22 . The product of  claim 12 , in which the extraction is conducted with a supercritical fluid at pressures of greater than 600 bar (60.0 MPa) and temperatures of between about 80 to about 120° C. 
     
     
         23 . The product of  claim 22 , in which the supercritical fluid is carbon dioxide.