黄花鱼腌制加工过程的脂肪氧化分析

摘要

目的：阐明多脂黄花鱼(yellow croakers)腌制加工过程的理化变化对脂肪氧化的影响以及脂肪氧化的内在机制。方法通过测定大黄鱼腌制加工过程中鱼肉理化指标(水分、盐分、pH 值)，脂质氧化指标[硫代巴比妥酸值(TBARs 值)、过氧化值(POV 值)]及脂肪氧合酶(LOX)活力的变化，研究加工过程中脂质分解氧化规律及其与水分、盐分、pH、LOX活力的相关性。结果随着加工的进行，水分出现3次显著性减少(P<0.05)，分别在腌制3 d、烘干1 d以及成品；盐分在腌制3 d时达到最高值6.38%；氧化指标POV和TBARs都呈现先升后降的趋势，分别在腌制3 d和烘干1 d达到最高值为0.907 meq/kg和0.250 mg/kg； LOX活性则呈现递减的趋势。POV值仅和盐分呈显著正相关(P<0.05)， TBARs则分别和盐分、水分呈极显著正、负相关(P<0.01)， LOX酶活与盐分、TBARs呈极显著负相关(P<0.01)。结论在多脂黄花鱼的腌制过程中，适当的盐度和水分的减少可促进脂肪氧化，而脂肪氧合酶的活性可被盐抑制，酶促反应不是引起脂肪氧化的主要原因。%Objective To illustrate the physical and chemical changes on the influence of lipid oxidation and the inner mechanism of lipid oxidation during processing of salting fatty fish of yellow croaker. Methods Lipid oxidation during processing of salting fatty fish of yellow croakers were studied by evaluating the changes in physicochemical parameters(moisture content, salt content, pH), lipid oxidation index [peroxide value (POV), thiobarbituric acid reactive substances (TBARs)], and lipoxygenase (LOX) activities and their correlation.ResultsAlong with the processing, moisture content significantly decreased (P<0.05) at salting for 3 d, drying for 1 d and final product; the salt content reached the peak of 6.38% at salting for 3 d; POV and TBARs increased first and then decreased, and reached the peak at salting for 3 d and drying for 1 d, respectively. The peak value was 0.907meq/kg and 0.250 mg/kg, respectively; the LOX activity was decreased during processing. The correlation result showed that POV was only positive related to moisture content (P<0.05), and TBARs was significantly positive and negative related to salt content and moisture content (P<0.01), respectively, and LOX activity was only significantly negative related to salt content (P<0.01). ConclusionsProper salinity and reduction of water can promote lipid oxidation, but activity of LOX is inhibited by salt, and enzymatic reaction may not be the main cause of lipid oxidation in salting fish of fatty yellow croaker.