冷热激处理对不同鲜切蔬菜衰老生理机能的影响

Effects of cold shock and heat shock treatments on senescence physiological of fresh-cut vegetables

为探究冷激和热激处理抑制鲜切蔬菜衰老的效果及机制,选取生理生态特性差异较大的甘蓝、洋葱和胡萝卜作为试材,冷热激处理后于20℃贮藏,比较了不同冷热激处理的感官品质,分析了冷热激处理对衰老生理指标及抗氧化酶活性的影响。结果表明,甘蓝冷激0℃ 20min和热激35℃ 1min,洋葱冷激0℃ 5min和热激48℃ 10min,胡萝卜冷激0℃ 50min,可以有效抑制感官品质下降;这些冷热激处理可延缓鲜切蔬菜衰老,可溶性糖和蛋白质的减少及丙二醛(MDA)的积累被抑制,并伴随有超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性提高及过氧化物酶(POD)活性降低。适宜的冷热激处理可诱导调节鲜切蔬菜抗氧化酶活性,延缓衰老和品质下降,不同鲜切蔬菜的冷热激保鲜处理条件差异较大,不适宜的冷热激处理可能会加速组织衰老。

Preservation effects and the mechanism of cold and heat shock treatments on fresh-cut vegetables were investigated to promote practical application. Cabbage,onion and carrot with different physiological and ecological characters were fresh-cut and treated by cold and heat shock treatments,then stored at 20℃. Sensory quality, senescence physiological indicators （soluble sugar, soluble protein and malondialdehyde （MDA）） and antioxidative enzymes （superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD）） activities were analyzed during storage. Experimental results showed that 0℃ 20min and 35℃ lmin for cabbage,0℃ 5min and 48~0 10min for onion and 0℃ 50min for carrot all could delay the decline of sensory score. These treatments could inhibit the accumulation of MDA,delay the reduction of soluble sugar and protein,induce the SOD and CAT activities and inhibit POD activity. Moderate cold and heat shock treatments could induce and regulate antioxidative enzymes activities,delay senescence and quality deterioration, Instead ,high intensity cold and heat shock treatments might accelerate deterioration of fresh-cut vegetables. Cold and heat shock treatments suitable for different vegetables had significant difference.