复热处理的鲈鱼挥发性成分分析

采用电子鼻和SPME-GC-MS联用技术对复热处理的鲈鱼挥发性成分及含量进行测定。结果表明:冷藏过程中,鲈鱼醛类含量呈现先降低后升高的趋势。与冷藏处理相比,复热处理在13 h后壬醛、1-辛烯-3-醇的总峰面积为29.98×10^7,增加了8.8×10^7,说明复热处理加速了鱼肉脂肪氧化,使得腥味增强。电子鼻可以较好地区分出冷藏3 h、8 h、13 h、18 h后鲈鱼肉气味的差别。DFA分析显示冷藏和复热处理均表现出3 h、8 h气味较为接近,13 h、18 h气味较为接近。主成分分析表明,较于冷藏处理,复热处理的鲈鱼随着处理时间的延长,使得鱼肉腥味加重,其中壬醛、1-辛烯-3-醇的特征向量分别为0.810、0.621,成为主要表现腥味的挥发性物质,并且这两种物质是冷藏13 h、18 h复热时鲈鱼的主要挥发性物质。

Volatile Components of Reheated Lateolabrax japonicus

The volatile components and their contents of reheated Lateolabrax japonicus were determined by SPME-GC-MS coupled with electronic nose. The results showed that the content of aldehydes in the fish flesh decreased first and then increased during cold storage. Compared with the cold storage treatment, reheating for 13 h increased the total peak area of nonanal and 1-octene-3-ol to 29.98×107 (increased by 8.8×107), indicating that reheating could accelerate the oxidation of fish fat and enhance the fishy smell. The electronic nose could distinguish the smell of the flesh refrigerated for 3 h, 8 h, 13 h and 18 h respectively. DFA analysis showed that the fleshes subjected to 3-h and 8-h treatment (reheating or cold storage) resembled in the smell, with those treated for 13 h and 18 h also having similar smell. The principal component analysis showed that compared with the cold storage treatment, reheating increased the fishy smell with the extension of time, with the eigen vectors of nonanal and 1-octene-3-alcohol b 0.810 and 0.621, respectively (which were the main volatile substances responsible for the fishy smell, and represented the major volatile compounds for the reheated flesh after a cold storage for 13 or 18 h).