Impact of Enzymatic Hydrolysis on the Structural Characteristic and Flavor Profile of Porcine Blood Meal Hydrolysates: Insights From FT‐IR, CD, and HS‐SPME‐GC‐MS

As a rich source of bioactive compounds, porcine blood meal was served as raw material in this study to elucidate the effects of diverse protease treatments on the composition, distribution, structural characteristics, and flavor compound content of the resulting hydrolysates. Gel permeation chromatography, spectroscopy, sensory evaluation, and headspace solid-phase microextraction gas chromatography techniques were employed for comprehensive analysis. The findings revealed that enzymatic hydrolysis significantly facilitated protein degradation in porcine blood meal, with the flavor protease treatment exhibiting the most pronounced effect, achieving a hydrolysis extent of 16.4%. Notably, the enzymatic hydrolysis primarily generated peptide fractions with molecular weights less than 1 kDa, which were most abundant in samples treated with flavor protease, accounting for 75% of the total peptides. A significant increase in surface hydrophobicity of the hydrolysates was observed following flavor protease treatment (P < 0.05), accompanied by notable improvements in sensory properties. The enzymatic hydrolysis triggered the structural transformation from α-helix to random coil and β-sheet structure. Among the thirty-five volatile flavor compounds identified in the hydrolysates, eleven were deemed as characteristic flavor compounds. The samples subjected to treatment with flavor protease demonstrated a statistically significant increase in the concentrations of 1-octene-3-ol, trans-2-octenal, and 3-methylbutyraldehyde (P < 0.05).