LIANG Shihui, FENG Yumin, DENG Huarong, LIU Qiaoyu, BAI Weidong, WU Junshi, CHEN Haiguang
From the aspects of protein oxidation characteristics, aggregation degree, protein structure, and histological characteristics, the effects of different thawing methods (room temperature thawing, flow thawing, cold storage thawing, and microwave thawing) on the physical and chemical properties of frozen chicken thigh myofibrillar protein were explored. Results showed that the carbonyl content of thawed at room temperature was the highest, 3.63 nmol/mg, and the sulfhydryl content and Ca2+-ATPase activity were the lowest, 110.55 μmol/g and 0.72 U/mg, respectively, indicating that the protein oxidization in the room thawed group was the most severe. The light chain band was fuzzy and slightly degraded. The content of β-turn (26%) and the content of random curl (31%) in the Raman spectroscopy results were relatively high, and the stability of the protein structure was poor. The degree of protein oxidation of hydrolyzed fluid was lighter, which was characterized by its lowest carbonyl content and surface hydrophobicity, 0.97 nmol/mg and 10.36 μg, respectively, and the highest Ca2+-ATPase activity at 2.95 U/mg. At the same time, the tissue structure was tight, the α-helix content was the highest (58%), and the protein secondary structure was relatively complete. The loss of sulfhydryl groups in cold storage and thawing was the smallest, the content of sulfhydryl groups was 258.23 μmol/g, the color of the myosin light chain was darker, there was an aggregation phenomenon, and the tightness of tissue structure was not significantly different from that in the fluid thawing group. The tissue structure of microwave thawing was severely damaged, the muscle fiber gap was large, the protein secondary structure was disordered, and the α-helix content was the least, which was 29%. Therefore, flow thawing could be used as the main thawing method for thawing chicken thigh meat.
