Study On Residues Dynamic Transformation Rules And Removing Methods Of Zeranol And Acetamiprid

Nowadays, the food safety problems related to the fresh food have always broken out in China. Especially, the residues of pesticides and veterinary drugs caused the most negative impact to human health. Therefore, in order to ensure food safety, some simple, fast and reliable detection methods must be established to monitor the drug residues in food. Studying on degradation rules and removal methods could be helpful to guide the use of pesticides and veterinary drugs, reduce the residues and ensure food safety. The main research results were as follows:1. The enzyme-linked immunosorbent assay (ELISA) for zeranol has been optimized. The conditions for experiment are as follows:the dilutions of coating antigen and antibody are1:500and1:5000; the concentration of coating antigen is2μg/mL; coating time is4℃overnight; blocking solution choose3%OVA in PBS, blocking time is2h; solvent is10%methanol in PBS.The relationship between ELISA and HPLC was studied (y=1.025x+0.1353, R2=0.9839). The coefficient of variation in ELISA and HPLC is less than6.37%and3.44%, respectively. Although the precision in ELISA is lower than HPLC, it was suitable for detection of zeranol. The pretreatment of zeranol for ELISA was also studied, and proved suitable for detecting.2. In order to reveal zeranol degradation rules under different conditions, spiked pig livers were treated by different methods at different storage conditions. With increase of storage time, degradation speed of zeranol became flat. The zeranol in the samples stored at4℃was degraded faster than in the ones stored at-20℃, and the residues of zeranol in the steamed samples was lowest. Nevertheless, final residues of zeranol in three samples were less than30.1%. In order to safeguard consumers’ interests, we must decrease the residues of veterinary drugs.3. The residues of acetamiprid on cucumbers was determined under different removal treatments, including storage, water rinse at different temperature for different time, water rinse plus ultrasonic wave and detergents with different concentration. The results indicated that:the degradation rates increased with temperature rose and time prolonged, and with increase of storage time, degradation speed of acetamiprid became flat. Consider of the cucumber quality and time rationality, the best treatment has been determined, the best way is water rinse at40℃for15min, with removing rate of71.75%. Water rinse at20℃for10min plus0.1%detergent treatment may remove50.65%of acetamiprid residues in cucumbers, and the removing rate in0.2%detergent treatment is52.13%. In order to decrease the pollution of detergents,0.1%detergents treatment was chosen to be the better way. Water rinse plus ultrasonic wave was also effective to remove acetamiprid residue, the maximum removing rate is56.76%. The effects of cooking methods on degradation were also found out. The results indicated that:among the three ways of cooking (steam, boil, and fry), the degradation were different. Boiling was the most effective method on degradation, and the removing rate is82.41%.