The invention provides a preparation method for
small peptide protein of
sardine. The preparation method comprises the following steps: (1) taking the African
sardine, removing surface scales and internal organs, cleaning up,
slicing,
steaming, pressing, crushing, adding water, and obtaining
sardine-
powder solution; adding 0.05 to 0.5 percent of compound
enzyme into the sardine-
powder solution to carry out enzymolysis, wherein the compound
enzyme is mixed by
alkaline protease and
trypsin according to the
mass ratio of 1 to (1 to 5); maintaining the enzymolysis temperature to be 30 to 70 DEG C, firstly adjusting the PH value to 7 to 8, carrying out enzymolysis for 1 hour, then adjusting the PH value to 7 to 8, continuously carrying out enzymolysis for 3 to 10 hours, and obtaining enzymolysis mixture containing the
small peptide protein; then carrying out
enzyme-deactivating treatment; passing through a vibratory
sieve and collecting filtered solution; carrying out
centrifugation on filtered solution to collect supernatant, carrying out
ultrafiltration to collect filtered solution, carrying out vacuum concentration, spraying,
drying and obtaining the
small peptide protein. The preparation method provided by the invention is simple and controllable, and the obtained small
peptide protein is relatively stable in component and content and can be used as an excellent
animal feed.