不同冷冻温度对鲅鱼理化指标及新鲜度的影响

Effects of Different Freezing Temperatures on Physicochemical Properties and Freshness of Spanish Mackerel

以pH、挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、硫代巴比妥酸值(thiobarbituric acid,TBA)和肌原纤维蛋白含量等理化指标,结合感官评价,分析了-50、-30和-18℃3种冻结温度下鲅鱼新鲜度差异。采用电子鼻技术,获取了不同冻结温度处理后鲅鱼的气味信息,利用主成分分析(principal component analysis,PCA)法处理了电子鼻气味信息数据,建立一种快速区分鲅鱼新鲜度的方法。结果表明,不同冻结温度处理后鲅鱼的新鲜度存在显著差异(p <0.05),-50℃冻结组综合新鲜度显著优于另两组,其中TVB-N和TBA值显著低于另外两组(p <0.05),而pH和肌原纤维蛋白含量显著高于另外两组(p <0.05),同时,-50℃冻结组感官评分也优于其他两组。电子鼻结果显示,电子鼻对各个温度下冻结的鲅鱼肉响应灵敏,区分结果同理化和感官评价结果相一致,能有效区分出不同冻结温度下鲅鱼肉气味差异,表明电子鼻技术可以作为一种区分冻结鲅鱼新鲜度的快速检测手段。

To investigate the effects of freezing temperatures（-50,-30 and-18 ℃ ）on fi＇eshness of Spanish mackerel, indexes such as pH, volatile basic nitrogen （ TVB- N ） value,2- thioharbituricacid （TBA） value, the content of myofibrillar protein of the mackerel samples and sensory evaluation were measured.Using electronic nose technology, the smell information of Spanish mackerel ＇after different freezing temperature treatment was obtained.The information data of electronic nose odor was analyzed by principal component analysis（PCA） , and a rapid method to distinguish the freshness of Spanish mackerel was established. The results showed that there was significant distinction on freshness of the Spanish mackerel between different freezing temperatures（p 〈 0.05 ）.The freshness of mackerel samples under -50 ℃ freezing with fridge freezer was the best,the TVB-N and TBA value were significantly lower than the other two groups （p 〈 0.05 ） , while the pH and content of myofibrillar protein was significantly higher than the other two groups（p 〈 0.05 ）.At the same time, the sensory score of the freezing group at -50 ℃ was also better than the other two groups.According to the results of electronic nose,electronic nose could sensitively response to mackerels which well distinguish the different freezing temperatures. And the results were consistent with the results of physical and chemical and sensory evaluation.So the electronic nose could he used as a rapid detection method to distinguish the freshness of Spanish mackerels.