Techniques Of Determination And Degradation Of Pesticide Residues In Strawberry

With the gruadual increase of the cultivated area of anti-season strawberry, pesticides were abused by producer who didn't have enough knowledge about the safe and appropriate usage of pesticides so that the pesticide residue exceed standard limits and harm to human health. After entering into WTO, the standard of monitoring pesticide residue in China was enhanced. Therefore, in order to ensure the quality and reduce the hazard of pesticide, the analysis of the pesticide residue was needed, which was important on imposing management of pesticide, guiding safe and scientific use pesticide, preventing pollution and safeguarding human health.The research utilized strawberry as test material. Degradative effects of chlorphrifos in strawberry and the changes of strawberry quality by dipping strawberry in 2,4,6,8,10% hydrogen peroxide and 0.02%,0.2%,1%,2% peroxyacetic acid for 5min,10min,20min were studied. The main results were as follows:1. To some extent, the hydrogen peroxide had effect on degradation and removal to dispose of chlorphrifos in strawberry . The treatment of dipping in 10% hydrogen peroxide for 20 min was the best to dispose chlorphrifos. The degradation rate was 71.99%。But the appearance of the strawberry were fade and wiltingContrasting with all treatments, the effect on destroying quality of strawberry by dipping in 2% hydrogen peroxide for 5min and 10min were relatively weak. Meanwhile, dipping in 2% hydrogen peroxide for 10 min was the best way to dispose chlorphrifos which could be used as pesticide residue remover in strawberry.2. The peroxyacetic acid had effect on degradation and removal to dispose of chlorphrifos in strawberry . With the increase of add amount of peroxyacetic acid and the prolong of treatment time, the pesticide residue was decreased. The degradation effect was the best by dipping in 2% peroxyacetic acid for 20 min in strawberry. But owing to the effect of peroxyacetic acid on the qulity of strawberry, whether use it to dispose of chlorphrifos in strawberry or not need more synthetical researches.The research indicated that with the increase of add amount of peroxyacetic acid and the prolong of treatment time,the content of reducing sugarand Vc in strawberry declined gradually ;the titrable acidity advanced gradually .The effect of destroying the strawberry quality by dipping in 0.02% peroxyacetic acid for 5min,10min,20min and 0.2% peroxyacetic acid for 10min are relatively minor. Meanwhile, dipping in 0.02% peroxyacetic acid for 20 min was the best way between the several treatments above to dispose chlorphrifos which could be used as pesticide residue remover in strawberry.