高能电子束辐照对巨峰葡萄生理品质的影响

【目的】探讨高能电子束辐照对巨峰葡萄的保鲜效果,为电子束在葡萄等果蔬类保鲜领域的应用提供理论及实践依据。【方法】以400、700、1000、1500、2500Gy等不同剂量电子束处理巨峰葡萄,置于温度-0.5—0.5℃、相对湿度85%—95%冷库中贮藏,研究不同处理对巨峰葡萄生理品质的影响。【结果】400、700、1000Gy剂量电子束辐照巨峰葡萄并结合低温冷藏能够有效抑制Vc及单宁含量的下降,维持较高的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性,抑制膜脂过氧化进程,进而达到保鲜的目的。其中700Gy处理组贮藏后期Vc含量达3.79mg/100g,SOD、POD活性分别保持在14.89U.g-1、40.93U.g-1.min-1,显著高于其它处理组(P0.05),且能维持较低的腐烂率和落粒率;而1500、2500Gy电子束对葡萄的品质产生一定负面影响,贮藏期间Vc、单宁含量快速降低,果粒落粒现象较重。【结论】700Gy电子束处理巨峰葡萄其生理品质及保鲜效果最佳,在-0.5—0.5℃冷库中贮藏98d,与对照相比极大提高了贮藏品质。

Effects of High Energy Electron Beam on Physiological Quality of Kyoho Grape

Objective] The preservation effects of high energy electron beam on Kyoho grapes were studied for providing a theoretical and practical basis of application in the fruits and vegetables storage field. Method] The Kyoho grapes were put in cold storage of-0.5-0.5℃, RH 85%-95% after irradiation of 400 Gy, 700 Gy, 1 000 Gy, 1 500 Gy, and 2 500 Gy and the physiological quality was studied during storage. Result] The results showed that the dosages of 400 Gy, 700 Gy, and 1 000 Gy could control the decline of ascorbic acid and tannin content effectively, maintain higher activity of superoxide dismutase(SOD), peroxidase(POD), catalase(CAT) enzymes, restrain the degree of membrane lipid peroxidation with low temperature. The treatment of 700 Gy couldmain lower rotting rate and shattering rate.The V_c content was 3.79mg/100g and the activity of SOD and POD were 14.89U·g~(-1) and 40.93U·g~(-1)·min~(-1),witch were higher than the other groups observably(P<0.05).However,the treatments of 1 500 Gy and 2 500 Gy had undesirable effects on product quality. The content of Vc and tannin decreased rapidly, and the phenomenon of shattering was more serious than other groups. Conclusion] The Kyoho grape could keep its physiological quality and fresh-keeping effect at the best state under 700 Gy irradiation. The storage quality was improved obviously compared with the control group preserved for 98 days at -0.5-0.5℃.