抗氧化乳酸菌对发酵腌干带鱼脂肪氧化的影响及其主成分分析

摘要

将从传统腌干鱼中筛选出的3株具有抗氧化活性乳酸菌(干酪乳杆菌、植物乳杆菌和戊糖片球菌)作为发酵剂加入到腌干带鱼中,测定pH值、过氧化值、酸值、硫代巴比妥酸值和正己醛含量等指标,以监测发酵腌干带鱼加工过程中脂肪的氧化程度,并分析了乳酸菌发酵对腌干带鱼成品脂肪酸组成的影响.结果表明,在腌干带鱼生产过程中抗氧化乳酸菌对不饱和脂肪酸的氧化有一定的抑制作用,接菌发酵的腌干带鱼过氧化值、硫代巴比妥酸值、正己醛含量和饱和脂肪酸含量显著低于传统腌干带鱼,而酸值和不饱和脂肪酸含量高于传统腌干带鱼.对测定的指标进行主成分分析的结果表明,第1主成分能反映脂肪水解程度,其线性回归函数为:Y1=0.131X1+0.208X2+0.360X3+ 0.2 44X4+ 0.083 X5-0.38 8X6+ 0.32 4X7+ 0.343 X8;第2主成分能反映脂肪氧化程度,其线性回归函数为:Y2=0.330X1 +0.406X2+0.182X3+0.440X4+0.294X5-0.205X6+0.135X7+0.157X8.本研究为提高发酵腌干鱼的安全性提供理论依据.%Three lactic acid bacterial (LAB) strains (namely Lactobacillus casei,Lactobacillus plantarum and Pediococcus pentosaceus) with antioxidant activities,screened from traditional dry-cured fish,were used as starter culture to ferment drycured hairtail.The changes in lipid oxidation of dry-cured fermented hairtail during processing were determined in terms of pH value,peroxide value,acid value,thiobarbituric acid reactive substances (TBARS) value and hexanal content.Moreover,the effect of LAB fermentation on the fatty acid composition of dry-cured hairtail was analyzed.All indices were analyzed by principal component analysis (PCA) eventually.The results indicated that LAB fermentation could inhibit the oxidation of unsaturated fatty acids.The peroxide value,TBARS value,hexanal content and staturated fatty acid content of fermented dry-cured hairtail were significantly lower than those of traditional dry-cured hairtail,but the acid value and unsaturated fatty acid content were significantly higher than those of traditional dry-cured hairtail.The first principal component reflected the degree of lipolysis,while the second principal component reflected the degree of lipid oxidation.And the principal component functions were Y1=0.131X1 + 0.208X2 + 0.360X3 + 0.244X4 + 0.083X5-0.388X6+ 0.324X7 + 0.343X8 and Y2=0.330X1 + 0.406X2 + 0.182X3 + 0.440X4 + 0.294X5-0.205X6 + 0.135X7 + 0.157X8,respectively.These results provide a good theoretical basis for controlling the safety of fermented dry-cured fish.