Optimizing Enzymatic Processes for Enhanced Nutritional and Organoleptic Properties of Chicken Bones

The increasing demand for poultry products has led to significant by-products, with chicken bones being a rich source of proteins and minerals. The protease hydrolysis of chicken bones has emerged as a key method for extracting chicken bone protein. The objective of this study was to optimize enzyme combinations and hydrolysis reaction conditions to enhance both the nutritional value and quality of the product. Through univariate experiments and response surface methodology, the optimal enzymatic hydrolysis conditions were determined as follows: 55 °C, 1.5 h, and composite enzymes comprising papain (2.53%), bromelain (4%), and flavorzyme (4%) (w/w). The peptide content of the hydrolysis product obtained with the composite enzyme reached 336.78 mg/g, with small molecular peptides (<500 Da) accounting for 95% of the composite enzyme hydrolysis product. These small molecular peptides are more readily absorbed by the human body. Additionally, the free amino acids significantly increased, particularly those more easily absorbed by the human body such as glutamic, glycine, and aspartic. Moreover, there was a notable increase in the volatile flavor compounds including aldehydes and alcohols, which enhanced the flavor profile by producing fatty or mushroom-like aromas. This method enhances protein recovery and sample quality, converting chicken bone waste into valuable ingredients, contributing to sustainable food practices and innovative consumables for both pet and human consumption.