Study On Degradation Technologies Of Pyrethroids And Carbamate Pesticides In Apple Juice

Pesticide residue is one of the bottleneck problems to restrict the international development of apple juice concentrate (AJC), and also is the chief security problem of AJC's export to America and European Union. Studying and developing new high efficiency, safe, environment-benefiting, economical and practical pesticide residue decrease or elimination techniques are urgent needed in the AJC industry, and also has important significance on constructing green and security protection barrier of apple-apple juice. The degradation of pyrethroids and carbamate pesticides in clean apple juice and the influence of main chemical and physical indexes of apple juice(soluble solid concentration, total sugar, total acid, transmittance and color value ) after treatment of ultralsonic wave, 60Co-γray irradiation and ultra high pressure was studied systematically in this paper. The main experiment results are as the following:1. Ultrasonic wave can degrade pyrethroids and carbamate pesticides in apple juice greatly. The optimal treatment condition of pyrethroids is power 300W, time 45min, temperature 55℃, the degradation rate of pyrethroids by this condition is: permethrin 96.42%, cyfluthrin 92.97%, flucythrinate 91.76% and deltamethrin 100.00%; The optimal treatment condition of carbamate pesticides is power 240W, time 30min, temperature 50℃. the degradation rate of carbamate pesticides by this condition is: lannate 66.74%, primicarb 77.51% and carbofuran 75.84%; Ultrasonic wave treatment has little influence on the quality of apple juice, the color value reduced slightly, the soluble solid concentration, the total sugar,the total acid and the transmittance almost unchanged.2. 60Co-γirradiation can degradate pyrethroids and carbamate pesticides both effectively: when the irradiation dose is 9kGy, the degradation rate of pyrethroids is Permethrin 65.72%, cyfluthrin 94.14%%, flucythrinate 72.41% and deltamethrin 67.84%; When the irradiation dose is 7kGy, the degradation rate of carbamate pesticides is lannate 61.64%, primicarb 76.55% and carbofuran 63.17%; 60Co-γirradation could affect main chemical and physical indexes of apple juice to some extent, the soluble solid concentration and the total sugar decreased slightly, the total acid increase slightly, the transmittance and the color value significantly increased.3. The effect of ultra high pressure treatment on the degradation of pyrethroids and carbamate pesticides in apple juice is significantly. When the pressure is 300MPa, time is 45min, the degradation rate of permethrin, cyfluthrin, flucythrinate is 100%, and deltamethrin is 96.28%; when the pressure is 300MPa, time is 5min, the degradation rate of carbamate pesticides is lannate 61.86%, primicarb 66.91%, carbofuran 74.27%. Ultra high pressure treatment also has little influence on the quality of apple juice.