The invention belongs to the technical field of
collagen peptide preparation, and particularly relates to a method for producing
collagen peptide by using cod
skin as a
raw material. The method comprises the following steps: cleaning cod
skin, adding a gradient
sodium chloride-
citric acid aqueous solution, stirring and soaking, dropwise adding a
calcium bicarbonate aqueous solution, continuouslysoaking, filtering after soaking, cleaning the cod
skin with deionized water, airing the
surface moisture of the cod skin, adding an
acetic acid solution and
sodium alginate, swelling, pulping, adjusting the pH value, obtaining
fish skin pulp for later use; and adding
papain and
squalene into the
fish skin pulp, carrying out enzymolysis, carrying out
enzyme deactivation after the enzymolysis is finished, centrifuging, taking the supernatant, carrying out
ultrafiltration on the supernatant, and carrying out
freeze drying. According to the extraction method provided by the invention, the collagen body yield can be increased, the extracted
collagen peptide is high in purity, uniform in molecular
weight distribution, high in
oxidation resistance and free of peculiar smell, the bitter and fishysmell of the collagen
peptide prepared from aquatic products is reduced to the maximum extent, and the enzymolysis time is greatly shortened.