Effects Of High Energy Electron Beam And Ozone On Kyoho Grape Storage Quality

Grape (Vitis vinifera Linn.) is one of the foremost cultivated, the most widely distributed fruit tree in the world. Grape fruits are easy to rotting, threshing, stem drying and stalk fading during storage, which have bad impact in the transport, storage, marketing and so on, result in great economic losses. Lots of pesticides are necessary to kill pests and diseases because of rich nutrients and susceptible during the cultivation. However, pesticide residues in food have caused widespread concern along with heavy use of pesticides. The article studied on physiological effect of high energy electron beam and ozone on Kyoho grape storage quality, in order to provide theoretical and practical base for application of new grape preservation methods. Meanwhile, we researched the degradation effect of high energy electron beam and ozone on chlorothalonil and beta-cypermethrin pesticide.1. The Kyoho grapes were put in cold storage of -0.5~0.5℃, RH 85%~95% after irradiation of 0.4, 0.7, 1.0, 1.5, and 2.5 kGy. The result showed that high energy electron beam could control the propagate of bacteria, mildew, yeast, coliform bacteria, alleviate putrefaction and deterioration of grapes during storage. Below the dosage of 1.0 kGy, the respiration intensity was restrained effectively, the decreaseing of titratable acid, ascorbic acid and tannin content was prevented, and higher activity of SOD, POD, CAT enzyme was maintained. The Vc content was 3.79 mg/100g of 0.7 kGy treatment, the titratable acid and total soluble sugar content were 0.348%, 11.44%, and the activity of SOD, POD was 14.89 U·g-1, 40.93 U·g-1·min-1,which higher than the the control significantly(P<0.05). Redundant free radicals were romoved by protective enzyme, which alleviated injury by MDA accumulating and inhibited PPO enzyme activity better. It could reduce the degree of browning, keep fresh state of peel, stem, accordingly control the maturity and senescence of grapes effectively.2. Pathogenic organisms were inhibited and killed more effectively, the reduce of titratable acidity, Vc and tannin content were slowered by electron beam combined with appropriate SO2. The Vc and tannin content of treatment 0.7 kGy were 4.03 mg·100g-1, 49.4 mg·100g-1at 98 d which significantly higher than the other treatments(P <0.01), and it could inhibit the fruit browning and the loss of green, to keep fresh appearance quality.3. Fruits were stored at temperture of -0.5 to 0.5℃, with RH 85 % to 95 %, and treated with ozone concentration of 21.04, 44.62, 81.41, 131.14 mg·m-3. The results showed that treatment of ozone concentration 81.41 mg·m-3 (250 mg·h-1, 2min), once a week, kept 1 h, could control the propagate of bacteria, mildew, yeast, coliform bacteria, alleviate putrefaction and deterioration of Kyoho grape markedly. The sound berry rate was 85.42% at 98 d, higher than the other groups(P<0.05). It could restrain respiration intensity, alleviate the decline of Vc, soluble solids, titratable acidity content. Meanwhile it could maintain higher activity of SOD, POD, CAT enzyme, alleviate the degree of membrane lipid peroxidation. Therefor it could delay the maturing and aging of fruit obviously.4. The high energy electron beam had notablely degradation effect on chlorothalonil and beta-cypermethrin. Pesticide degradability increased with higher dosage of electron beam. The degradation rate of chlorothalonil and beta-cypermethrin increased to 64.26%, 48.89% at 4.0 kGy. The degradation effect of ozone water was obviously with degradation rate up to 51.92%, 26.12% at 13.97 mg·L-1.