Food science and Technology Letters

32-35

Authors: SHEIKH S.A., NIZAMANI S.M., MIRANI B.N., MAHMOOD N

The study was conducted to assess the effect of household processing methods such as washing, sun drying, cooking/ frying and blanching on the decontamination of bifenthrin and profenofos residues in experimentally grown bitter gourd. Simple washing of bitter gourd with tap water reduced the residues of bifenthrin to 50.62% and that of profenofos to 53.66%. Subsequent washing with detergent solution indicated a reduction of 59.78 and 65.85% in bifenthrin and profenofos residues respectively in the bitter gourd. Blanching as a processing tool has exerted a more protective effect with a drop of 80.71% in bifenthrin and 78.05% profenofos residues. A significant decrease in bifenthrin (89.65 %) and profenofos (87.92%) residues was also observed by plain washing followed by sun drying. Frying appeared to be the most effective technique to minimize bifenthrin and profenofos residues to the extent of 93.41% and 88.68%, respectively, suggesting that frying is the most potent protective food processing approach to curtail bifenthrin and profenofos in bitter gourd.

41-45

Authors: SHEIKH S.A., NIZAMANI S.M., PANHWAR A.A., MIRANI B.N

Pesticide residues were determined in marketed samples of different vegetables. Samples were collected from different markets of southern Sindh during 2012-13. Residues were extracted with QuEChERS method and were analyzed with Gas Chromatography (GC) coupled with Mass Spectrometry Detector. However, emamectin benzoate and imidacloprid were analyzed with High Performance Liquid Chromatography (HPLC) coupled with Ultraviolet (UV) detector. The insecticide residues in vegetable samples were quantified by using the standards. Results showed that seven vegetables namely okra, bitter gourd, brinjal, tomato, onion, cauliflower, and chilies, were heavily contaminated with chlorpyrifos, profenofos, endosulfan, imidacloprid, emamectin benzoate, lufenuron, bifenthrin, diafenthiuron, and cypermethrin. Moreover, every vegetable was contaminated with more than one pesticide and majority of samples violated the Japanese MRLs. Desi spinach, lettuce, bottle gourd, fenugreek, peas, and cluster bean are not sprayed with pesticides normally, but these were found contaminated with trace level residues within MRL(s). This could be due to contaminated soil (from previous crops) and/or may be due to vegetable vendors’ mishandling as they use the same water for washing vegetables in series which is a common practice all over Sindh. Present study recommends that vegetables may be washed thoroughly prior to use and water may be changed after each vegetable wash or washing of vegetables may be done under running tap water in order to minimize pesticide contamination.