Patent ID: 6204362
Filing Date: 2001-03-20
Classification: A23C,A61K,A61P,C07K

Abstract:
In a method of purifying whey separated from lactic acid fermentation liquid by electrodialysis wherein said whey contains angiotensin-converting enzyme inhibiting peptides, the improvement which comprises carrying out said method using an anion exchange membrane having a permeability of diffusion coefficient in the range of 3.0 to 9.0.times.10.sup.-6 cm/sec, wherein the diffusion coefficient of the anion exchange membrane is determined by:(a) maintaining a first 0.5 normal sodium chloride solution on one side of the anion exchange membrane in a vessel, and maintaining a second 3.0 normal sodium chloride solution on the other side of the membrane in said vessel;(b) stirring the first and second sodium chloride solutions;(c) measuring the differences in the concentration of the two sodium chloride solutions, and(d) calculating the diffusion coefficient by applying the formula:Diffusion coefficient (cm/sec)=transferred amount of sodium chloride(mol/sec)*area of membrane(cm.sup.2)*.DELTA.C(mol/cc).