Influence of heat pre-treatment on BSA tryptic hydrolysis and peptide release

In contrast with other food proteins, such as β-lactoglobulin or caseins, intensely studied for bioactive peptide production, relatively little attention has been paid to serum albumin, the main blood protein, even though blood disposal is a severe problem for meat processors. In this study, serum albumin was hydrolysed with trypsin after several heat treatments and using different enzyme concentrations. The degree of hydrolysis reached and the peptide sequences released over time were evaluated. Large differences in enzyme-to-substrate ratios (1:50, 1:100 and 1:200) led to similar degree of hydrolysis values (31.92 ± 1.43%, 31.08 ± 3.09% and 26.21 ± 0.71%), and did not alter the number of peptides released. However, thermal treatment enhanced significantly (p < 0.05) both the degree of hydrolysis (up to 50.41 ± 1.90%) and the number and amount of the majority of peptides obtained, all with potential bioactivity (28 peptides in the native hydrolysate, 39 in the thermally treated).