Studies On The Preservation Technology Of Fresh Zanthoxylum Schinifolium Sieb Et Zucc. And Degradation Thchnology Of Pesticides On Z.S.sieb Et Zucc.

In this paper, using the fruits of Zanthoxylum schinifolium sieb et Zucc. as raw materials, we discussed the effects of degradation methods of pesticide residues, technology of modified atmosphere packaging with cold storage, and preservation at room temperature in long term.The research work mainly included as follow:(1) The technology of modified atmosphere packaging with cold storage of Z.S.sieb et Zucc. was established. In this paper, researched the influences of fungicides, preservatives, temperature,and different original atomosphere of modified atmosphere on the color, and rotting rate.Then the orthogonal test results show that:Z.S. sieb et Zucc. was treated 30min by ozone, then painted by 1% chitosan, kept them at 0℃by using modified atmosphere,the original atomosphere of modified atmosphere was 5%O2+15%CO2+80%N2. At this situation, Z.S. sieb et Zucc. could be kept as long as one month.(2) In this paper, researched the influences of preservatives, sterilization temperature,and sterilization time on the color, and PPO activity. Results show that after immersing in 400 mg/L zinc acetate solution for 30 min, we had 100g Z.S. sieb et Zucc.within 5 g/L Vc solution vacuum packed, then kept them at 100℃for 8 min. The final products can be kept 2 months.(3) We used 4 pesticides which were dimethoate,chlorothalonil,acetochlor,deltamethrin as the main pesticides on Z.S. sieb et Zucc.The method of detecting 4 pesticide residues on the gas chromatography(GC) was optimized.Conditions:the detector and injection port temperatures were set at 300℃and 265℃, respectively. The column temperature program:from 80℃(holding for 2 min) to 212℃at 40℃/min (holding for 7 min), then rose to 280℃at 20℃/min (holding for 8 min). The carrier gas flow rate was 1.63 mL/min, and tail-blowing flow rate was 50.8 mL/ min. The injection volume was 1μL, and inject mode was non shunt injection. Under these conditions, we detected the volume of 4 pesticide sandards. Their standard plasmids have good linear range. The corrlation coefficient was 0.9947-0.9992, and the recovery was 78.1%-121.6%, and the coefficient of variation was 2.51%-14.58%. The precision and accuracy of the method is good enough.so the method could be used in pesticide residues analysis of Z.S. sieb et Zucc.(4) The effects of six different degradation methods of pesticide residues in Z.S. sieb et Zucc. were discussed. The methods are ozone treatment, ultrasonic treatment, ultraviolet irradiation, detergent immersion,brine immersion,sodium carbonate solution immersion. The results indicated that the best method was using ozone treated 60min.The average degrading rate was over 80%,meanwhile the quality of Z.S. sieb et Zucc. has little changes. After the ozone treatment,△a was 1.04, loss quantity of volatile oil was 0.7146 mL/1 OOg; on the third day after treatment,△a was 1.52.