Abstract: To investigate the effect of protein denaturation caused by high-temperature heat treatment during the sterilization process on the nutrient digestibility of soybean protein, we simulated in vitro the infant digestion of soybean protein. Results showed that high-temperature heat treated (> 120 ℃, 20 min) soybean protein could generate more enzymatic hydrolysates with low molecular mass compared to that treated at 100 ℃. Meanwhile, the high temperature treatment could induce a significant loss in amino acids, especially cysteine (approximately 48%), destroying the ideal amino acid pattern and decreasing the nutritional value of soybean protein.

Key words: high-temperature heat treatment, soybean protein, digestibility, amino acid composition and content, protein aggregation