Chicken cruor (Ch-cru), a protein-rich slaughterhouse by-product, has potential as a sustainable source of antimicrobials. This study investigated the impact of peptic hydrolysis duration (up to 24 h at pH 3) and a subsequent chemical discoloration step on the degree of hydrolysis, peptide profiles, and antimicrobial activities of hydrolysates adjusted to pH 4 or 9. Hydrolysates obtained after 0.5 h showed notable antifungal activity (9.31–19.10 mm). Crude hydrolysates at pH 9 after 6–24 h inhibited Listeria ivanovii , whereas discoloration induced a bioactivity shift toward Gram-negative bacteria, with discolored hydrolysates at pH 9 after 0.5 h active against Escherichia coli . PLS-DA linked antimicrobial activity to peptide populations, identifying 23 candidate peptides, five showing antifungal activity after synthesis. One peptide exhibited the highest activity (MIC 0.0098 ± 0.00 mM). Overall, hydrolysis duration and discoloration strongly influenced antimicrobial properties, supporting Ch-cru valorization as a natural bio-preservative within a circular economy approach. • Peptic hydrolysis (pH 3, 24 h) of chicken cruor gave distinct peptide profiles • Both short and long hydrolysates inhibited E. coli and Listeria ivanovii
Rahimi et al. (Sun,) studied this question.