Recovery of amino acids and peptides from pig bone soup using thermal pre‐treatment and enzymatic hydrolysis

Pig shoulder bones, by-products from the meat industry, are rich in protein and could be used to produce high amino acid products for food processing. In this study, after formulating the bone soup by heating it in water, we optimized the hydrolyzing process of the bone soup using three commercial enzymes (Flavourzyme, Protamex, and Alcalase). Alcalase hydrolysis gained the highest soluble protein recovery efficiency of 70.45% at the optimum condition, including hydrolysis temperature of 56°C, hydrolysis time of 138 min, and E/S ratio of 2.3%. The Alcalase hydrolysate achieved the peptide average molecular weight of 532 Da. In terms of nutritional value, the amino acid content gradually increased from the samples hydrolyzed with Alcalase, Flavourzyme, and Protamex (15.96, 16.60, and 20.71 mg/ml, respectively). However, the hydrolysate using Alcalase was the most favorable sample in sensory evaluation. Novelty Impact Statement Optimized soluble protein recovery of amino acids and peptides via enzymatic hydrolysis is essential to attain the highest possible nutritional value from raw materials like pig bone. Besides, thermal pretreatment and fat removal were implemented to identify soluble protein recovery efficiency (SPRE) precisely.