Enzymatic Hydrolysis Of Chicken Protein And The Preparation Of Meat-like Flavor By Maillard Reaction

The meat-like flavor, that produced mainly with the hydrolysates of animal protein, cysteine and deoxidized sugar by Maillard Reaction, have the characteristic of savageness material, purity and long haul meat-flavor, high resist-oxidation. They are abroad used in the food of convenience noodle, soup material, convenience meal and so on, to increase or improve the meat flavor of the food. In these years, more and more attention have been taken in meat-like flavor the international, but there are fewer in our country.In this paper, we choose chicken breast meat as the substance of the enzyme, which have a high content of protein but low price. They were hydrolyzed by Papain, Neutrase, Flavourzyme and compound enzyme respectively.The results showed that Papain/Flavourzyme = 1:1 (P&F compound enzyme) was the most effective compound enzyme. The effect of enzyme/substrate ratio, substrate concentration, original pH and hydrolysis temperature on the Degree of Hydrolysis were studied. And the optimized hydrolysis conditions were: enzyme/substrate ratio of 500 u/g protein, substrate concentration of 7%, original pH = 7.0, temperature of 60℃. In this codition, the DH can achieve more than 30% after two hours.Then, a simple model of Maillard Reaction system was established. The model was composed of the essential materials for Maillard Reaction: hydrolysates of chicken protein, cysteine and glucose. The effect of hydrolysis time of chicken meat, dosage of cysteine and glucose on flavor of Maillard Reaction product were determined. And an optimized ratio among the materials were obtained. Then the optimized temperature, pH and reaction time for Maillard Reaction were determined. The result show that the optimized conditons of the simple model of Maillard Reaction system were: hydrolysis time of 2 hours for chicken meat, 50 mL hydrolysate of chicken meat, 0.6 mol/L glucose, cysteine/glucose = 1:3, temperature of 115℃, original pH = 6.0, reaction time = 40 min.Then, we made some improvement for the simple model of Maillard Reaction system. The effect of the addition of VB1, chicken fat, HVP and amino acid of no sulfur element were determined. The result showed that 3.37g VB1, 3g chicken fat, 4g HVP, gly/Ala ( Moore ratio ) = 1:2, ( gly + Ala )/cysteine ( Moore ratio ) = 1:1 were the optimal additons. Finally, the quality and quantity of flavor volatiles from cooked chicken meat and maillard reaction product were ditermined by Head Space Solid Phase MicroExtraction ( HS-SPME ). In the retention time of 32 min, 31 volatiles were identified in the cooked chicken meat, and 56 volatiles in the Maillard Reaction product. In the Maillard Reaction product, it mainly contained 11 Alcohols, 7 Aldehydes, 4 kentones, 6 esters, 6 furan, 5 thiazole, 2 pyrazine, 3 pyrrole and so on. And there were 17 volatiles In the Maillard Reaction product were same as the cooked chicken meat. And some character volatiles of chiken meat-like flavor and meat-mike flavor were ditermined, for example: nonanal; lactone; furan-1- 2-penthyl; 5-thiazole ethanol, 4-methyl and so on.