Abstract:

Pigskin soluble collagen was prepared by enzymolysis in addition of weak acid at 4 ℃, and then dried into powder, and the remaining pigskin was further grinded in the presence of ethanol to prepare insoluble collagen powder. The extraction technology of soluble collagen was optimized by orthogonal test, and the ethanol concentration for preparing insoluble collagen powder was selected. Besides, the collagen content and functional properties of the two collagen powders were analyzed. Results showed that the addition of acetic acid was able to enhance the swelling of pigskin and the dissolution rate of soluble collagen. The optimal extraction conditions of soluble collagen with pepsin were as follows: enzyme concentration 0.2%, solid to liquid ratio 1:15, pH 2.0 and hydrolysis time 48 h, and under the above conditions the yield of soluble collagen was 0.602%. 60% ethanol was the best for preparing insoluble collagen powder. The collagen contents of obtained soluble collagen powder and insoluble collagen powder were 95.1% and 82.9%, respectively. Both the two collagen powders exhibited good functional characteristics. The results suggested the feasibility of this technology for the production in plant scale.

Key words: pigskin collagen, pepsin, functional properties