| Chicken bone is one of staple byproducts of poultry-processing. However, chicken bone has not been pay much attention to recycle, and the bulk of this material is being either discarded or partly used. Hence, further development of this material using bio-enzymatic and Maillard enhancing aroma reaction techniques in this thesis means much for improving this situation and facilitating sustainable development of poultry-processing industry.The composition of chicken bone showed it had high content of protein, and the ratio of constituent amino acid indicated that chicken protein had high content of necessary amino acids, umami amino acids, and what's more, had a good taste in its extraction solution. Five Proteases (Pancreatin, Papain, Alcalase, Protamex, Flavorzyme) were employed to hydrolyze chicken bone. The content of soluble nitrogen, amino nitrogen were obviously increased after treated by protease and the content of them was increased as the hydrolysis time increased. The result obtained from SEC profile of different hydrolysate showed that higher molecular weigh fractions in peptide decreased and smaller one in peptide increased as hydrolysis time increased. This suggested that the molecular weight distribution profile and functional properties of hydrolysates could be controlled by using relevant protease.During chicken bone treated by Pancreatin, almost all free amino acid content increased as hydrolysis time prolonged, in which hydrophilic amino acids and amino acids in main cleavage site of Pancreatin were preferred to liberate. In initial stage of chicken bone treated by pancreatin, hydrophilic amino acid was liberated more preferablely than hydrophobic amino acid, the mole ratio of hydrophilic amino acid, However, when extensively hydrolyzed, more and more hydrophobic amino acid was liberated from peptide bonds due to treated by Pancreatin. The amino acid liberation rule during chicken bone treated by protease caused important effect on qualities of hydrolysates, and the 4 hr hydrolysates of Pancreatin had best savory characteristics.The volatile compounds in chicken bone hydrolysates was rich and owned highest content of aldehyde, including some important chicken charateristics flavor compounds. The results of volatile compounds in flavor concentration of chicken bone hydrolysates with and without protease treatment showed that lever of volatiles were influenced obviously by protease treatment and protease treatment was help for strengthening chicken characteristic flavor. Meanwhile, thermal inactivation procedure would improve the lipid aroma, meat flavor and the whole flavor quality of chicken bone hydrolysate. The conditions for Maillard reaction to produce chicken process flavorings optimized by the Friedman methodology. The GC-MS results of chicken flavor showned that, aldehydes, alcohols and heterocyclyclic compounds were the major volatile compounds and accounted for 78.51% in all volatile compouns, thus, the chicken flavor was good in chicken characteristic flavor and meat flavor when prepared on the base of chicken bone hydrolysates.The degradation peptide fractions in chicken bone hydrolysate during Maillard reaction showed that it was related with hydrolysis degree of chicken bone hydrolysates and molecular weight of peptide fractions. The length of peptide fractions was responsible for influencing the peptide fraction degradation in Maillard reaction. The results of component amino acid in chicken bone hydrolysate peptide showed that hydrophilic amino acid had a higher degradation degree in thermal degradation reaction and a milder degradation degree in Maillard reaction when compare to hydrophobic amino acids. The GC-MS analysis of chicken bone hydrolysate peptide fractions Maillard reaction with glucose showed that nitrogen-containing heterocyclyclic compounds was the dominating component in volatile compounds, among which pyrazines were major compounds and pyrazines accounted for 34.04% in all identified compounds.
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