青核桃冷藏期间氧化状态分析

Analysis of oxidation status of walnutwith husk during cold storage

为了解青核桃在冷藏期间的氧化状态,该文以青核桃为材料,研究其在低温冷藏中果仁含水量、酸价(AV)、过氧化值(POV)、碘值(IV)、过氧化氢酶(CAT)、脂氧合酶(LOX)、丙二醛(MDA)的变化。结果表明:冷藏期间,青核桃果仁水分含量、IV呈逐渐降低趋势;CAT活性保持良好;AV、POV、LOX活性、MDA含量总体上表现为上升趋势;主体间效应检验得出,冷藏时间对青核桃品质影响显著(P<0.05)。IV、果实含水量两两之间均呈极显著性正相关(P<0.01),AV、POV、LOX及MDA两两之间表现为极显著性正相关(P<0.01);部分指标呈(极)显著性负相关;主成分分析结果表明,果仁含水量、AV、POV、IV、MDA、CAT、LOX与果实品质关系密切,可作为评价其氧化程度的重要指标。青核桃采摘预冷后,在温度为1~2℃、相对湿度为85%~90%的条件下可贮藏18 d。以上结果可为青核桃冷藏提供理论依据和基础数据。

In this research,the changes of moisture content,acid value(AV),peroxide value(POV),iodine value(IV),catalase(CAT),lipoxygenase(LOX)and malondialdehyde(MDA)of walnut with husk were studied to understand the oxidation status of walnut with husk during cold storage.The results were as follows:During cold storage,the moisture content and IV decreased gradually;The CAT remained good;The AV,POV,LOX activities and MDA content showed an increasing trend;The inter-subjectivity effecting test showed that the effect of cold storage time on the quality of walnut with husk was significant(P<0.05).Studies have shown that there was a very significant positive correlation between the IV value,moisture content with kernel(P<0.01),in addition,there was a very significant positive correlation between the AV,POV,LOX and the MDA(P<0.01);Some of the indexes were(extremely)negatively correlated with each other;The result of principal component analysis showed that the moisture content and AV,POV,IV,MDA,CAT,LOX were closely related to the quality of the fruit,and it could be used as an important index to evaluate the degree of oxidation.The walnut with husk could be stored for 18 days at 1-2℃and RH 85%-90%,after walnut with husk was picked and precooled.This research will provide theoretical basis and basic data for walnut with husk during cold storage.