Studies Of Bass Protein Hydrolysis Process Optimization And Active Peptide Functional Properties

Bass is a marine low-value fish, world protein deficiency is still a serious problem facing mankind, and the fish with high rate of absorption and utilization, which has a large amount of high quality and the amino acid ratio is very close to the human muscle composition, is an important resource to solve this problem. In my paper, marine bass as the material was bought from market which was dried、shattered and defatted to make the bass protein powder, Then trypsase were used to prepare smaller relative molecular bass peptides by hydrolysising bass protein and optimal hydrolyze process was determined. Besides, the bass protease solution products are separated into different molecular weight range of peptides. The ability of peptides combined bile salts is the indicator to judge the cholesterol-lowering effect of bass peptides. This paper is mainly discussed the cholesterol-lowering effect and mechanism of bass peptides in vitro, in addition, it also studied the processing properties of different components. The research aims at providing theoretical bases for the development of health products made by marine low-value fish protein peptides, so as to improve the effective utilization of marine low-value fish. This article was mainly studied as follow:1. Enzymatic hydrolysis of efficient preparation of bass protein peptide:To optimize the preparation of small molecular weight peptide from bass protein by sequentially hydrolyzing, trpsase were used and different hydrolysis time, temperature, pH and enzyme were investigated, which respectively affected the bass protein degree of hydrolysis (DH). Considering the various factors to determine the optimal conditions were as follow:the bass proteins were hydrolyzed by trypsase, dosage of20000U/g, in the condition of pH8.5,40℃for5hours. The degree of hydrolysis of hydrolysates respectively reached12.5%.2. Bass protease solution purification separation:Bass protein peptides were separated and purified by the method of gel chromatography and five components were isolated, which were analyzed by MALDI mass spectrometer. Moreover, the bass protein and the enzymatic hydrolysates were analyzed by Tris-SDS-PAGE electrophoresis. The results indicated that the molecular weight of the separated components are mainly distributed under10kD and in the form of small molecular peptides.3. The cholate combining experimental research of different components of bass protease solution products:This research simulated the conditions of human digestion and compared the ability of peptides combined bile salts by bass protein and different components of the enzymatic hydrolysates in vitro. The results show that the hydrolysates after5h has the strongest ability in combining bile salts; the lower concentration is,the stronger ability is; the smaller molecular weight components have stronger combining ability.4. The comparison of processing properties before and after bass protein enzymolysis:Compared the changes of solubility, water absorption, oil absorption, emulsifying stability, foaming and foam stability before and after bass protein enzymolysis. It turned out that solubility increased with the increase of pH and the solubility after enzymolysis is better than before; the water and oil absorption of bass protein is better than the enzymatic hydrolysate; emulsifying properties were effect by different levels of pH, protein concentration, oil content, ionic strength and other factors, the emulsification after enzymolysis is better than before and the emulsion stability enzymolysis after20min is better than lOmin later; the foam ability after enzymolysis is better than before and with the increase of time, foam stability decreased.