Enzymatic Hydrolysis Of Chicken Bone Paste And The Study On The Application Of Its Products

The research was focused on the following key points. Chicken bone paste was firstly treated by enzymes to made hydrolyzed animal protein (HAP). Then the HAP was used to prepare the chicken flavorings through Maillard reaction and the volatile components in which were analyzed. The process of chicken flavorings production was studied in detail.Complex flavoured enzyme 1,Protamex,Alcalase,neutral protease 2, trypsinase, AS.1398 neutral protease and papain were selected to hydrolyze the chicken bone paste. Enzymolysis was evaluated by a series of indicators, such as flavor of the hydrolysate, degree of hydrolysis (DH), nitrogen recovery and so on. The results showed that the DH of HAP was higher after chicken bone paste hydrolyzed by Alcalase, neutral protease 2 or AS.1398 neutral protease than by the others. The flavor of the HAP, however, was better by the hydrolysis of complex flavoured enzyme 1 or papain, which had no bitterness and strange odour. Then the combinations of two enzymes were further studied. After single factor and orthogonal tests, the optimal hydrolysis conditions were determined. Preheating treatment at 90℃for 30min can promote the enzymolysis. The ratios of enzyme and substrate for the neutral protease 2 and Complex flavoured enzyme 1 were 0.75% and 2%, respetively. Hydrolyzed by the combination of neutral protease 2 and complex flavoured enzyme 1 at the temperature of 50℃, pH7.0 for 4hrs, with the substrate concentration of 5 %( w/w), the DH and nitrogen recovery of the hydrolysate can reach 40% and 90%, respectively, which has no bitterness and strange odour, but has 30% ACE inhibitory activity.HAP was used as main material to produce chicken flavoring. The addition of chicken fat could give a characteristic profile of chicken flavor. The optimal formula and process conditions were as follows: 60%water content, 15.13%glucose, 15.13%pentose 1, 1.37%hydrochloricde cysteine, 1.37% amino acids 2, 6%HAP, 1%fat, , pH 5.0, reaction temperature 110℃for 30 minutes. By sensory evaluation, the flavor of the product was similar to that of natural chicken soup.