扁舵鲣脂肪氧化分析及其对肌红蛋白氧化的影响

Analysis of fat oxidation of auxis thazard and its effect on myoglobin oxidation

研究了扁舵鲣肌肉中几种挥发性成分对肌红蛋白(Mb)氧化的影响。采用气相色谱分析扁舵鲣脂肪酸的组成特点,再利用顶空固相萃取和气质联用仪(GC-MS)分析贮藏中鱼肉挥发性物质的组成及变化规律,并从中挑选七种脂质氧化代谢产物,在不同p H值下研究其对Mb氧化的影响。由GC分析结果可知,扁舵鲣脂质中不饱和脂肪酸的比例较高,在暗色肌和普通肌中的比例分别为62. 76%和47. 75%。GC-MS分析结果显示鱼肉挥发性物质主要以醛类、醇类、酮类和杂环类物质为主,其相对含量呈现较规律变化趋势(醇类逐渐增加、醛类逐渐减少)。各氧化产物对Oxy Mb具有促进氧化的作用,影响为醛类>呋喃类>酮类>醇类,醛类中不饱和醛的促氧化作用大于饱和醛((E,E)-2,4-庚二烯醛>苯甲醛>壬醛>己醛),且各物质在低p H值条件下更能促进Mb氧化。

The effects of several volatile components in the muscles of the auxis thazard on myoglobin(Mb)oxidation were studied.Gas chromatography was adopted,and the composition characteristics of auxis thazard fatty acids were analyzed,and headspace solid phase extraction and gas chromatography-mass spectrometry(GC-MS)were used,and the composition and change law of volatile components in fish during storage were analyzed,and seven kinds of lipid oxidative metabolites were selected from them,and the effects of them on Mb oxidation were studied at different p H.According to the analysis results of GC,the proportion of unsaturated fatty acids in the lipids of the auxis thazard was higher,and the proportions in the dark and normal muscles were 62.76%and 47.75%,respectively.The results of GC-MS analysis showed that the volatile components in fish were mainly aldehydes,alcohols,ketones and heterocyclics,and relative contents showed a relative regular change trend(alcohols gradually increased and aldehydes gradually decreased).Each oxidation products had an effect on promoting oxidation of Mb,and the effect was in sequence of aldehyde,furan,ketone and alcohol.The prooxidant effect of unsaturated aldehydes in aldehydes was greater than that of saturated aldehydes((E,E)-2,4-heptadienal>benzaldehyde>furfural>hex-anal),and each substance could promote Mb oxidation in low pH conditions.