| Meat from spent hens is generally tough and poor in functional properties. Hence, the value of the spent hens is low. Therefore, utilizing spent hens as flavoring should increase the value. This study was conducted to investigate spent hen composition and effects of various enzymes (papain, bromelain, trypsin, and Aspergillus oryzae protease) in hydrolysis of spent hen breast meat. Spent layer carcasses were obtained from a commercial spent hen processing plant in North Mississippi. Each portion and composition of spent hen carcass were determined. Ground breast meat, water, and enzyme were mixed and hydrolyzed in a water bath at 50°C for four hours. The enzyme activity was terminated by placing the reaction bottles in boiling water for 15 min. Optimal pH and concentration condition were determined by proteolytic activity of each enzyme. Proteolytic activities of selected enzyme combinations were also investigated. A quantitative descriptive analysis (QDA) technique was used for aromatic, feeling factor, and taste analyses of spent hen hydrolysates. Based on the proteolytic activity, sensory characteristics, and enzyme cost, two optimal enzyme combinations were selected for product manufacture. Yields, moisture content, and microbiological analyses (Total aerobes, Salmonella , and E. coli/Coliform) of final hydrolysate products were determined.; Optimal pH for enzyme hydrolysis of spent hen breast meat suspension was 5.0--7.0 for all enzymes. Papain and Aspergillus oryzae protease at the 1.0% level showed the highest (P < 0.05) hydrolysis efficacy, followed by 0.5% (w/w) and 0.1% (w/w). Papain + Aspergillus oryzae protease and papain + Aspergillus oryzae protease + bromelain were chosen for product manufacture. Salmonella and E. coli/Coliform were not detected in all final products. |
