Study On The Changes Of Protein And Taste Substance In The Process Of Enzymatic Hydrolysis Of Pig Bone Extract

The enzymatic hydrolysis technology was used on controllable degradation of porcine ossein, which was extracted form fresh porcine bones, for improving the flavor characteristics and developing its application. In my project, orcine ossein was enzymatic hydrolyzed by flavourzyme, papain hydrolyzate, composite pretease and trypsin. Its degree of hydrolysis and variation of soluble nitrogen under different treatments were analyzed; its degradation and enzymolysis liquid peptide molecular weight distribution were determined by Tricine-SDS-PAGE electictropherogram. Variation of flavor amino acid before and after degradation were analyzed by Antomatic Amino Acids Analyzer; variation of volatile flavor compounds before and after enzymatic degradation were analyzed by GC-MS technology.The results showed that in the process of enzymatic hydrolysis, four enzymes’ hydrolysis and TCA soluble nitrogen gradually increased with the enzymatic conducting. However, this trend flattened while hydrolysis reached a certain time. The results of Tricine-SDS-Page electrophoresis showed that four kinds of proteases’protein bar gradually deepened with the conduct of the hydrolysis time:papain has nine protein bands, molecular weight of five bands were from14.4kD and35.0kD, and the remaining four are in under14.4kD; flavourzyme has only bands of molecular weight of about27.0kD during4h to8h, during12h to24h with enzymatic conduction, increased the bands molecular weight of47.0kD and50.0kD; pancreatin has eleven protein bands, molecular weight of two bands is about45.0kD, molecular weight of five bands is between14.4kD and35.0kD, and the remaining four is under14.4kD.The content and proportion of flavor amino acid before and after different enzymatic degradation were changed significantly. In the product of papain, pancreatin and the composite of the protease, the proportion of fresh sweetness amino acids and bitterness amino acid differed little. The ratio of fresh sweetness amino acid was around20%, and the ratio of bitterness amino acids was about50%. The proportion of fresh sweet amino acid was greater than the bitter taste amino acids in the flavor enzymatic hydrolysis liquid. So, flavor and papain enzyme to enzymolysis pig bones prime was chose to optimize strongly in bitterness of the papain single enzyme.Volatile flavor components in the flavor enzymatic hydrolysis liquid were determined by GC-MS, and38volatile flavor compounds were identified in pig bone prime:including18alcohols,8esters,6aldehydes,2ketones and4other substances, which increased to51after the flavor enzymatic hydrolysis. But pig bone enzymatic hydrolyzate, after flavor enzymatic hydrolysi,s were13species more than that of pig bone prime. Among them, the alcohol productse were14alcohols.13esters,8ketones,3acidsspecies,1aldehyde and12other substances (including nitrogen-containing sulfur-containing heterocyclic compound).