金枪鱼鱼白的植物乳杆菌发酵脱腥增香作用研究

Studies on the Deodorization during Fermentation of Tuna's Milt by Lactobacillus plantarum

目的:利用植物乳杆菌发酵金枪鱼鱼白来改善其风味,研究脱腥增香的效果,为水产品加工提供参考。方法:利用主成分分析(PCA)和特征风味雷达图来确定新鲜鱼白和发酵不同时间的鱼白及其发酵液的挥发性物质变化趋势,采用顶空固相微萃取与气-质联用仪(HS-SPME-GC-MS)对这个过程中的挥发性风味成分进行分析,结合感觉阈值,相对气味活度值(ROAV)确定发酵鱼白的主体风味成分。结果:PCA和雷达图显示新鲜鱼白与发酵鱼白的气味差异明显,发酵液的气味变化相对较小,较稳定。通过GC-MS在新鲜鱼白、种子发酵液、发酵12 h、24 h、36 h和48 h的鱼白及其发酵液中分别检测出22,13,12,23,35,34,11,13,15,17种挥发性物质。经过发酵的鱼白中庚醛、己醛、1-辛烯-3-醇等具有腥味的物质减少,具有奶香气味的己酸、2,3-丁二酮、乙偶姻等物质含量增加。这些物质是发酵鱼白中的主体风味物质。结论:植物乳杆菌发酵鱼白24 h后,其风味得到改善,脱腥增香的效果非常明显。

Objective: To analyze the effect of deodorization and aroma enhancement about the fermentation of Tuna’s milt by Lactobacillus plantarum and to provide a theoretical reference for processing. Methods: The change trend of volatile substances in milt and its fermented liquid was detected by principle component analysis(PCA) and features flavor radar. Then flavor of the volatile composition in the process was identified by head solid-phase microextraction(HSSPME) coupled with gas chromatography-mass spectrometry(GC-MS). The relative odor activity value(ROAV) in association with odor threshold was applied to confirm the key compounds of the fermented milt. Results: The PCA and radar map showed distinctly difference between the smell of fresh milt and fermentation milt. the smell of the fermented liquid change was relatively small and steady. A total of 22, 13, 12, 23, 35, 34, 11, 13, 15, 17 volatile substances were identified in fresh milt, seed fermented liquid, fermentation milt and its fermented liquid in different time. After fermentation of milt the main fishy smell compounds of heptyl aldehyde, hexanal, 1-octene-3-alcohol were reduced, while the milk fragrance compounds of caproic acid, 2,3-butyl ketone, ethyl benzoin were increased. These substances were main flavor of fermentation milt. Conclusion: After fermenting 24 h by Lactobacillus plantarum, the effect of deodorization and aroma enhancement was very remarkable.