Abstract:

The nutritional value of Chinese soft-shelled turtle leg muscle protein before and after heat treatment was
evaluated based on amino composition, in vitro and in vivo digestibility and protein digestibility-corrected amino acid score
(PDCAAS). The results showed that the contents of essential amino acids were 36.84% and 34.55%, respectively before and
after heat treatment. The ratios of total essential amino acids to total amino acids (TEAA/TAA) were 41.12% and 40.20%,
respectively, meeting the FAO/WHO standard. The in vitro and in vivo digestibility of Chinese soft-shelled turtle protein
were 83.68% and 95.05%, and increased to 87.04% and 96.18%, respectively after heat treatment. These results suggested
that heat treatment significantly increased the in vitro and in vivo digestibility (P ＜ 0.05). The PDCAAS of Chinese softshelled
turtle, as calculated by multiplying the limiting amino acid score by protein digestibility, reduced from 100% to
76.94% due to the nutrient losses during cooking.

Key words: Chinese soft-shelled turtle, in vitro digestibility, in vivo digestibility, protein digestibility-corrected amino acid scores (PDCAAS)