不同干燥方法对海鳗鱼片几种内源酶活力的影响

干燥能赋予水产品独特风味,而这些风味物质的形成与内源酶有关。本实验通过检测冰温真空干燥,真空冷冻干燥和热风干燥海鳗鱼片中对滋味起主要作用的内源酶(AMP脱氨酶、酸性磷酸酶、组织蛋白酶B和亮氨酰氨肽酶)活力和其催化形成的滋味物质(IMP和游离氨基酸)的含量,以探究不同干燥处理对内源酶的影响。结果表明:干燥后AMP脱氨酶、酸性磷酸酶、组织蛋白酶B和亮氨酰氨肽酶潜在活力均降低,真空冷冻干燥鱼片的4种酶活力保存率最高,分别为92.99%、85.58%、65.53%和54.26%,冰温真空干燥次之,热风干燥最低。不同干燥方法鱼片中IMP含量间有显著性差异,冰温真空干燥鱼片含量最高,从最初的174.37mg/100 g(干基)增加到625.08 mg/100 g,且游离氨基酸含量增幅最高,达33.07%。因此,冰温真空干燥的海鳗鱼片,4种酶活力保存较好,滋味物质含量最高。

Effect of Different Drying Methods on Several Endogenous Enzyme Activities of Muraenesox cinereus Fillets

Drying can endow aquatic products with unique flavor, whose formation is related to endogenous enzymes. In this study, the effects of different drying methods on enzyme activities and their metabolites inosinemonpho sphate (IMP) and free amino acid contents of Muraenesox cinereus fillets were investigated. Several enzymes playing the leading role in taste substances (such as AMP deaminase, acid phosphatase, cathepsin B and leucyl aminopeptidase) were selected. The drying methods included controlled freezing-point vacuum (CFVD), vacuum freeze drying (VFD) and hot air drying (HAD). Results showed that potential activities of the four enzymes mentioned above were decreased after drying. The highest retention of enzyme activities of fillets was observed in VFD, representing 92.99%, 85.58%, 65.53% and 54.26%, respectively, followed by CFVD. While HAD fillets had the lowest enzyme activities. The IMP and free amino acid contents in CFVD fillets were significantly higher than those in other treatments. IMP content increased from 174.37 mg / 100 g (dry basis) to 625.08 mg/100 g and free amino acid content increased by 33.07%. Therefore, four kinds of enzyme in CFVD fillets reach better retention in activities and the highest conversion rate.