Preparation of Gelatin and Collagen Peptides from Salmon Skin

Abstract:

Gelatin was extracted from salmon skin by acid leaching and water extraction. Ultraviolet spectrum with the maximum absorption wavelength was 233 nm，and amino acid composition testified that the extract conformed to the characteristics of gelatin. The gelatin extract rate was 60.46%，and the gelatin content in the extract was 83.92%. Papain was used for enzyme hydrolysis of gelatin to become collagen peptides which were low molecular weight. The effects of hydrolysis time，amount of enzyme，substrate concentration，pH and temperature on hydrolysis rate were investigated systematically. By orthogonal designed experiments，results showed that the optimal conditions of enzymatic hydrolysis was hydrolysis time 2.5 h at 55 ℃，amount of enzyme 7%，substrate concentration 10%，pH 8.0. At the optimum conditions，the hydrolysis degree was 12.65%. The collagen peptides from salmon skin had low molecular weight，whose molecular weight less than 1000 Da accounted for 91.5%.