臭氧处理对洞庭青鲫鱼肉挥发性成分的影响

Effects of ozone floatation on volatile components of Carassius auratus var.Dongting meat

为探究臭氧处理对洞庭青鲫鱼肉的脱腥效果,采用顶空固相微萃取结合气质联用仪分析脱腥前后洞庭青鲫鱼肉的挥发性成分变化,通过气味活度值(odor activity value,OAV)和正交偏最小二乘判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)确定腥味物质和脱腥效果。结果表明,洞庭青鲫鱼肉检测到的30种挥发性物质中,(E)-2-壬烯醛、正壬醛、(E)-2-癸烯醛、正己醛、(E,E)-2,4-癸二烯醛和1-辛醛对鱼腥味贡献较大;经臭氧脱腥处理后,挥发性成分减少,鱼腥味主要物质的含量和OAV均有所降低或脱除。OPLS-DA共筛选出6种特征标志物(VIP>1),分别为正庚醛、(E,E)-2,4-癸二烯醛、(E)-2-癸烯醛、(E,E)-2,4-庚二烯醛、(E)-2-壬烯醛和(E)-石竹烯。OPLS-DA和聚类分析表明,臭氧处理能有效减轻洞庭青鲫鱼肉腥味,可根据特征标志物含量有效区分不同脱腥程度的样品,最佳处理时间为5~10 min。该研究可为洞庭青鲫脱腥及加工提供参考。

To investigate the deodorization effect of ozone floatation on Carassius auratus var.Dongting meat,the volatile components in it before and after deodorization were investigated by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME-GC-MS).The odor activity value(OAV)analysis and orthogonal partial least squares-discriminant analysis(OPLS-DA)were used to determine fishy components and the deodorization effect.Results showed that 30 volatile substances were detected in the Carassius auratus var.Dongting meat.(E)-2-nonenal,1-nonanal,(E)-2-decenal,hexanal,(E,E)-2,4-decadienal,and 1-octanaldehyde contributed greatly to fishy odor.The volatile components were less by ozone floatation,and the content and OAV value of fishy components were reduced or not detected.Six characteristic markers(VIP>1)were screened by OPLS-DA,including heptaldehydehyde,(E,E)-2,4-decadienal,(E)-2-decenal,(E,E)-2,4-heptadienal,(E)-2-nonenal,and(E)-caryophyllene.OPLS-DA and cluster analysis showed that ozone floatation could effectively reduce the fishy odor of Carassius auratus var.Dongting meat,the sample at different deodorization time could be distinguished according to the content of characteristic markers,and the deodorization time should be controlled in the range of 5-10 min.This study provides a reference for the utilization and deodorization of Carassius auratus var.Dongting.