比较2种蓝圆鰺腌干工艺中脂质氧化与挥发性风味物质形成的关系

为探明鱼类腌制过程脂质氧化与特征风味物质形成的关系,以蓝圆鰺(Decapterus maruadsi)为原料,采用2种不同的腌干方法,传统高盐(traditional high salt,HS)法和低盐乳酸菌(low-salt lactic acid fermentation,LAF)法对其进行加工。测定2种工艺的腌干鱼加工过程中不同加工阶段脂肪氧合酶(lipoxygenase,LOX)、过氧化值(peroxide value,POV)、硫代巴比妥酸(thiobarbituric acid reactive substances,TBARS)值、主要挥发性风味物质的变化规律,利用Person相关系数分析2种工艺加工过程中脂质氧化、挥发性风味物质形成规律及两者之间的关系。结果表明:LOX活性均呈现先增加后降低趋势,除烘干末期之外酶活性HS法大于LAF法(P0.05),成品中LOX活性较鲜鱼分别增加了25%(HS)、34.8%(LAF);POV、TBARS值变化趋势与LOX变化趋势基本相同,烘干后期POV急速下降;成品中主要挥发性风味物质为醛、酮、烃、醇类物质,挥发性风味物质主要形成于烘干期间;LAF法生产的产品在HS法产品风味基础上增加了花香味;LOX与脂肪的氧化、风味物质形成之间具有一定的正相关性且脂肪氧化对风味物质的形成具有重要作用;LAF法更利于LOX发挥酶活力,促进风味物质特别是醛类物质的形成。

Comparison of the Relationship between Lipid Oxidation and the Formation of Volatile Flavor Components in Decapterus maruadsi during Two Different Dry-Salting Processes

In order to understand the relationship between lipid oxidation and the formation of flavor components in Decapterus maruadsi during two different dry-salting processes, i.e. traditional high salt (HS) and low-salt lactic acid fermentation (LAF), the changes in lipoxygenase (LOX), thiobarbituric acid reactive substance (TBARS) value, peroxide value (POV), and flavor components were measured. The relationship between lipid oxidation and flavor components was analyzed by the Pearson correlation coefficient. The results showed that LOX activity increased in the first three stages and then decreased in the final stage for both dry-salting processes, and it was higher in HS samples in the first three stages but lower in the final stage compared with LAF samples. LOX activities in the final dried products produced by HS and LAF were increased by 25% and 34.8% in comparison with fresh fish, respectively. The values of POV and TBARS showed similar changes to LOX, but POV decreased sharply in the final stages for both processes. The major volatile compounds of the final products, which were generated mainly during the drying period, were aldehydes, alcohols, ketones and hydrocarbons. Compared with HS, LAF additionally produced a floral flavor. A positive correlation was seen between LOX and fat oxidation as well as the formation of flavor substances, and fat oxidation played an important role in the formation of flavor substances. LAF could improve the activity of LOX and thus promote the formation of flavor substances, particularly aldehydes.