Abstract:

Whey protein concentrate (WPC) 80 was hydrolyzed with an enzyme complex consisting of alacase and papain (1:2 mass ratio) to prepare oligo-peptides in the present study. The hydrolysis conditions for the preparation of oligo-peptides were as follows: substrate concentration, 12 g/100 mL; reaction temperature, 50 ℃; and pH 9.0. The hydrolysate was ultrafiltrated through a sulfonated polysulfone membrane having a molecular weight cut-off (MWCO) of 10 kD under the conditions of normal temperature and 0.25 MPa working pressure difference and debittered by HZ00x resin adsorption. The resultant product had a little bitter taste and a light egg odor. The peptide yield was 36.54% under the above process conditions. The molecular weight distribution of peptides in the final product was mainly dipeptides, tripeptides and tetrapeptides, representing 27.45%, 34.88% and 26.65% of the total peak area, respectively.

Key words: whey peptide, enzyme, whey protein concentrate