Production of protein-polysaccharide conjugates

Abstract

The present invention provides novel compositions and methods for producing protein-polysaccharide conjugates in aqueous solutions. Also provided are methods for limiting the Maillard reaction to the very initial stage, the formation of the Schiff base. Provided are methods to obtain a simple product of Schiff base with white color, and compositions obtained using the methods of the present invention.

What is claimed is: 
     
         1 . A method of preparing a polysaccharide-protein conjugate, comprising reacting a polysaccharide comprising a reducing sugar and a protein hydrolysate in an aqueous solution under temperature conditions of from about 40° C. to about 120° C., thereby producing a polysaccharide-protein conjugate. 
     
     
         2 . The method of  claim 1 , wherein the solution is acidified to a pH of from about 6.0 to about 8.0. 
     
     
         3 . The method of  claim 1 , wherein the reducing sugar and protein hydrolysate are reacted under temperature conditions of from about 40° C. to about 120° C. for a period of from about 1 hour to about 48 hours. 
     
     
         4 . The method of  claim 1 , further subjecting the solution to a hydrostatic pressure in the amount of 1-20 MPa. 
     
     
         5 . The method of  claim 1 , further comprising the step of recovering the polysaccharide-protein conjugate from the solution. 
     
     
         6 . The method of  claim 1 , wherein the polysaccharide comprises dextran. 
     
     
         7 . The method of  claim 1 , wherein the protein hydrolysate comprises a hydrolysate of whey protein. 
     
     
         8 . The method of  claim 1 , wherein the protein hydrolysate comprises a hydrolysate of whey protein isolate. 
     
     
         9 . The method of  claim 1 , wherein the protein hydrolysate comprises a hydrolysate of β-lactoglobulin. 
     
     
         10 . A polysaccharide-protein conjugate obtained by reacting a polysaccharide comprising a reducing sugar and a protein hydrolysate in an aqueous solution under temperature conditions of from about 40° C. to about 120° C., thereby producing a polysaccharide-protein conjugate. 
     
     
         11 . The polysaccharide-protein conjugate of  claim 10 , wherein the polysaccharide comprises dextran. 
     
     
         12 . The polysaccharide-protein conjugate of  claim 10 , wherein the protein hydrolysate comprises a hydrolysate of whey protein. 
     
     
         13 . The polysaccharide-protein conjugate of  claim 10 , wherein the protein hydrolysate comprises a hydrolysate of whey protein isolate. 
     
     
         14 . The polysaccharide-protein conjugate of  claim 10 , wherein the protein hydrolysate comprises a hydrolysate of β-lactoglobulin. 
     
     
         15 . The polysaccharide-protein conjugate of  claim 10 , wherein the conjugate is comprised substantially of Schiff base. 
     
     
         16 . The polysaccharide-protein conjugate of  claim 10 , wherein the conjugate is substantially free of intermediate and advanced Maillard products. 
     
     
         17 . The polysaccharide-protein conjugate of  claim 10 , wherein the conjugate is white in color for a period of at least 3 months. 
     
     
         18 . The polysaccharide-protein conjugate of  claim 10 , wherein the conjugate is thermostable for a period of at least 3 weeks in solution held at about 5° C. 
     
     
         19 . A food composition with reduced allergenicity comprising as an allergenicity-reducing composition the polysaccharide-protein conjugate of  claim 10 . 
     
     
         20 . A method of producing a food composition with reduced allergenicity, comprising including in the food composition the polysaccharide-protein conjugate of  claim 10 .