热处理减轻黄瓜冷害作用机理的研究

Mechanism of heat treatment in reducing chilling injury of postharvest cucumber

以黄瓜(锦丰2号)为试材,研究热处理(37℃)对低温贮藏过程中黄瓜冷害发生、贮藏品质、生理生化变化等的影响,探讨热处理抑制黄瓜冷害发生的作用机理。研究表明,在0℃下,黄瓜贮藏3d后即出现冷害症状,9d后冷害发生严重,膜透性迅速上升,活性氧清除酶活性降低。热处理可以减轻黄瓜低温贮藏过程中的冷害指数,减缓叶绿素降解；热处理可以显著抑制黄瓜膜渗透率的升高,减少丙二醛的积累；提高自由基清除酶(SOD、POD、CAT)的活性。研究表明,热处理诱导活性氧清除酶活性,抑制膜脂过氧化作用,提高细胞内膜系统的稳定性,提高黄瓜对低温的适应和抵抗能力。

The cucumber “No.2 JINFENG” which was sensitive to chilling was selected as the testing material to investigate the role of HT（37℃） in inhibiting CI of cucumber. The occurrence of CI in cucumber, quality deterioration and the changing of physiological and chemistry after the treatment of HT during storage were also studied, Cucumber stored at 0℃ had slight chilling injury（CI） symptom only after 3 days and suffered severe CI when the storage duration exceeded 9 days with rapid increase in membrane permeability and reduction in activated oxygen scavenging enzyme activity, The index of CI and the content of chlorophyll in cucumber were all declining slowly in cold storage （0℃） after HT. The HT could retard the increase of membrane permeability significantly and decrease accumulation of MDA. The HT could improve the activities of POD, SOD and CAT during storage. The result showed that HT could maintain stabilities of cell membrane systems, retard the perexidation of membrane lipid, improve the ability of resistance and adaptation of cucumber to CI.