Patent ID: 6858234

Claim:
A process for a preparation of amylase inhibitor, comprising: (A) a step of obtaining an extract solution containing the amylase inhibitor by: (A1) extracting wheat flour or wheat gluten with water, an acidic aqueous solution, an alkali aqueous solution or an aqueous alcohol, (A2) extracting wheat flour or wheat gluten with water, an acidic aqueous solution, an alkali aqueous solution or an aqueous alcohol; acid-treating and/or heat-treating the resulting solution to denature the contaminants; and removing the denatured contaminants from the solution, or (A3) adjusting the pH of an extract solution containing the amytase inhibitor obtained in (A1) or (A2) within the range of 4.5 to 5.5, adding a polysaccharide to the solution to form an association product of the amylase inhibitor and the polysaccharide in the solution and then adjusting the pH within the range of 3.0 to 4.0 to form an insoluble complex of the amylase inhibitor and the polysaccharide; recovering the insoluble complex; and dissociating the polysaccharide from the insoluble complex in a liquid to remove the polysaccharide in an insolubilized form from the liquid; (B) a step of insolubilizing the amylase inhibitor by salting out by addition of a salt or salts to the amylase inhibitor-containing solution obtained in the step (A) and recovering the insolubilized substance resulting from the salting out; and (C) a step of directly drying the insolubilized substance recovered in the step (B) or dissolving the insolubilized substance in water to prepare an aqueous solution, and desalting and drying the aqueous solution to recover the amylase inhibitor.