From slaughterhouse waste to functional feed: pilot-scale bovine blood hydrolysate improves antioxidant activities and meat quality in slow-growing chickens.

Abstract

Bovine blood represents 4% of slaughter weight yet remains largely underutilised despite high protein content. This study scaled enzymatic hydrolysis from laboratory to pilot-scale production while evaluating bovine blood hydrolysate (BBH) as an alternative to commercial yeast hydrolysate (YH) in slow-growing chicken (Korat chickens) nutrition. Pilot-scale Neutrase hydrolysis of 400 kg batches achieved 15.08% degree of hydrolysis and 50.23% protein recovery, exceeding laboratory-scale performance. Comprehensive characterization revealed that BBH contained 59% of peptides within the bioactive 0.4 to 2 kDa range and exhibited 45.09% β-sheet secondary structure. Amino acid profiling demonstrated substantial enrichment in branched-chain amino acids, with leucine reaching 11,131 mg per 100 g representing 426% greater abundance than commercial YH. BBH exhibited superior in vitro antioxidant activities, achieving 335 µg Trolox equivalent per mL in ABTS radical scavenging compared to 271 µg for yeast hydrolysate and 122 µg EDTA equivalent per mL in metal chelating versus 90 µg for yeast hydrolysate. In vivo evaluation with 400 Korat chickens demonstrated that 0.1% BBH supplementation significantly enhanced antioxidant enzyme activities by 13 to 33% across superoxide dismutase, glutathione peroxidase, and catalase while maintaining growth performance equivalent to controls. Meat quality improved through 3.86% cooking loss reduction compared to unsupplemented controls (p < 0.05). Multivariate analysis confirmed functional equivalence between BBH and commercial YH. Therefore, pilot-scale BBH represents a sustainable technology converting meat industry waste into functional feed ingredients supporting enhanced animal health and product quality.