Production of bio-functional meat protein hydrolysate from Piaractus brachypomus using Pediococcus pentosaceus...

Rising demand for natural antioxidants and sustainable protein ingredients highlights the need for cost-effective and enzyme-free strategies to valorise fish resources. This study aimed to optimize fermentative hydrolysis conditions for producing biofunctional (antioxidant and antibacterial) meat protein hydrolysate from Piaractus brachypomus (PBMPH) using Pediococcus pentosaceus and to evaluate its physicochemical and functional properties. Response Surface Methodology revealed 2% sucrose concentration, 30% meat concentration, and 48 h fermentation time as the optimal conditions, yielding PBMPH with high degree of hydrolysis (49.68%), DPPH (24.78 μM TE/mg) and ABTS radical scavenging activity (21.87 μM TE/mg), ferric reducing antioxidant power (16.88 μM TE/mg), and iron chelation activity (15.97 μM EDTA/mg). PBMPH demonstrated antibacterial activity against major foodborne pathogens. PBMPH contained 71.94% protein with a balanced essential amino acid profile (46.63 g/100 g protein), particularly rich in lysine (8.49 g/100 g protein) and leucine (7.79 g/100 g protein), while maintaining low bioamine levels (<5 mg/100 g), indicating safety for consumption. SDS-PAGE revealed conversion of high molecular weight to low molecular weight peptides. FTIR spectra revealed the presence of β-sheet secondary structures. Moreover, PBMPH exhibited excellent functional properties, including high solubility (94.3%), foaming (FE 200.57%), emulsifying (EAI 17.60 m²/g), and water/oil absorption capacities (3.7 ml/g) over a wide pH range. Compared to previous studies, this work offers an eco-friendly, microbial fermentation-based approach that avoids commercial proteolytic enzymes and enables enhancement of antioxidant, functional, and antibacterial properties. Overall, the findings highlight the strong potential of PBMPH as a natural biofunctional ingredient for functional foods and nutraceutical applications.