Effects of Environmental Factors during Temporary Rearing on Physicochemical Properties and Texture Characteristics of Ictalurus punctatus Muscles
CHEN Yanan, LI Hailan, ZU Xiaoyan, LIAO Tao, LI Meijin, HUANG Jiajun, XIONG Guangquan
1.Institute of Agricultural Products Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; 2.School of Food and Biological Engineering, Hubei University of Technology, Wuhan 430000, China
Abstract：In this work, the effects of different environmental factors during temporary rearing on the physicochemical properties such as moisture content, pH and water-holding capacity and texture properties of Ictalurus punctatus muscle were investigated by controlling temperature at 12, 16, 20 or 24 ℃, ammonia nitrogen concentration at 0, 5, 10 or 20 mg/L and density at 1:2, 1:3, 1:4 or 1:5 (m/V). Our results demonstrated that in the 24 ℃ group, the water content and waterholding capacity of fish muscle were significantly (P < 0.05) lower than those in the other temperature groups. In the 12 ℃ group, the physicochemical properties were more stable, and the springiness and chewiness were significantly (P < 0.05) higher than those in the other temperature groups. When the concentration of ammonia nitrogen in the water was 0 mg/L, the pH of fish muscle was stable in the range of 7.12–7.15, and the water-holding capacity was maintained about 65%; the hardness decreased significantly with increasing rearing time (P < 0.05), and the springiness and chewiness increased, whereas the resilience and cohesiveness remained at a stable level. Moreover, the water content and water-holding capacity increased significantly (P < 0.05) with decreasing temporary rearing density up to 1:4 (m/V). At most temporary rearing times, the springiness of fish flesh in the 1:4 density group was significantly (P < 0.05) higher than that in the other density groups. With the extension of rearing time, the springiness and chewiness increased, and the resilience and cohesiveness decreased, while there was no significant change in the hardness or adhesiveness. In conclusion, the muscle quality of Ictalurus punctatus could be maintained or even improved in a temporary rearing environment with a temperature of 12 ℃, an ammonia nitrogen concentration of 0 mg/L and a density of 1:4 (m/V).
2021, Vol. 35 
