Bromelain-catalyzed hydrolysis of fish and poultry by-products: a sustainable approach to biopeptide production

This study aimed to develop bioactive protein hydrolysates from fish and poultry by-products using bromelain, an enzyme obtained from pineapple by-products, with potential applications in food and biotechnology. The global rise in protein-rich food consumption has led to increased generation of animal by-products from the meat and fish industries. These by-products are rich in protein, making them suitable for producing bioactive compounds. A multifactorial design was employed to optimize the hydrolysis process, evaluating key parameters such as enzyme-to-substrate (E/S) ratio and hydrolysis time. The optimal conditions were identified as 1.3% (E/S) for 240 min for fish by-products, and 2.0% (E/S) for 180 min for poultry by-products. These conditions were scaled up to produce fish (FH) and poultry (PH) hydrolysates. The hydrolysates showed high protein content (70.8 ± 0.1% for FH and 56.3 ± 1.0 % for PH), potent antioxidant activity (ORAC: 249.02 ± 4.71 µmol eq. Trolox/g for FH and 144.41 ± 11.62 µmol eq. Trolox/g for PH), and notable ACE inhibitory effects (IC₅₀: 693 ± 12 µg protein/mL for FH and 1585 ± 6 µg protein/mL for PH). Furthermore, hydrolysates promoted probiotic strains' growth, with 1% (w/v) FH or PH showing comparable performance to conventional culture media in supporting Lactobacillus casei 01 (p > 0.05). These results highlight the potential of bromelain-derived hydrolysates as sustainable, cost-effective alternatives to traditional nitrogen sources in functional fermented food or microbiological culture media. This study contributes to value creation from agro-industrial by-products and aligns with global sustainability initiatives by promoting circular bioeconomy approaches.