Abstract:

In this study, alcalase was applied to hydrolyze Langshan chicken breast meat. The results showed that the
optimum temperature, enzyme dosage and hydrolysis time for enzymatic hydrolysis of chicken protein were 45 ℃,
2.0 U/g, and 4 h, respectively. Many amino acids derived from sarcoplasmic and myofibrillar proteins were released during
enzymatic hydrolysis and soluble nitrogen was also accumulated in a large quantity. The molecular weights of peptides in
the hydrolysate were mainly distributed in the range of 30–50 kD. Aspartic acid and glutamic acid were the most abundant
amino acids in the hydrolysate with a ratio of hydrophilic amino acids (HLAA) to hydrophobic amino acids (HBAA) ranging
from 1.41 to 1.52. The analysis of the nutritional value of free amino acids indicated the presence of abundant quantities of
essential amino acids at different hydrolysis time and an essential amino acid index similar to the FAO/WHO recommended
value from the ideal amino acid pattern for adults.

Key words: Langshan chicken, alcalase, proteolysis, amino acids