(1.天津科技大学 食品科学与工程学院, 天津 300457;2.天津鸿腾水产科技发展有限公司, 天津 301800)
(1.College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China;2.Tianjin Hongteng Aquatic Science & Technology Development Co Ltd, Tianjin 301800, China)
以解冻损失率、蒸煮损失率、解冻pH值、蛋白质溶解性、水分分布等为指标,研究4 ℃解冻、室温解冻、流水解冻、微波解冻、超声解冻5 种解冻方式对冷冻泥鳅肌肉组织理化性质和微观结构的影响,并分析了各指标之间的相关性。研究结果表明:不同解冻方式对泥鳅鱼肉解冻损失率存在显著性差异(P<0.05)；流水解冻对泥鳅鱼肉解冻损失率、蒸煮损失率、pH值、蛋白质的溶解性影响最小；对各指标进行相关性分析,发现肌浆蛋白的溶解度与其他指标的相关性较好,都呈显著相关；采用扫描电镜观察解冻后的鱼肉的微观结构,解冻后泥鳅鱼肉的肌肉纤维间隙变大,其中,超声解冻的间隙最大,微波解冻后出现部分蛋白变性；采用低场核磁共振测定横向弛豫时间,发现解冻后泥鳅鱼肉的水分状态和含量发生变化。5种解冻方式中,流水解冻后的泥鳅鱼肉解冻损失率和蒸煮损失率最小,质构特性好,最终确定冷冻泥鳅的最优解冻方式为流水解冻。
Based on the thawing loss rate, cooking loss rate, thawing pH, protein solubility, water distribution and other indicators, the effects of 5 different thawing methods on the physicochemical property and microstructure of frozen loach muscle tissue were studied, including thawing with 4℃, room temperature, mobile water, microwave and ultrasonic, and the correlation between the indicators was analyzed. The results showed that there was a significant difference in thawing loss rate of loach muscle tissue thawing with different methods. In comparison with other thawing methods, there was the least influence on thawing loss rate, cooking loss rate, pH and solubility of protein after mobile water thawing. The correlation analysis of each index showed that the solubility of myogen was significantly correlated with other indexes. The microstructure of thawed loach muscle tissues was observed by scanning electron microscope. After thawing, the intramuscular space of loach was enlarged, and the largest space was found after ultrasonic thawing, and microwave thawing resulted in partially protein denaturation. The transverse relaxation time was measured by low-field nuclear magnetic resonance. And it was found that the water state and content of the thawing loach meats changed compared with the fresh sample. Among the five thawing methods, the thawing loss rate and cooking loss rate of water thawing were the least, and the texture characteristics were excellent. Finally, water thawing was the optimal thawing method for frozen loach.