EFFECT OF OZONE MICROBUBBLES WITH VARIOUS TEMPERATURES ON THE CHLORPYRIFOS INSECTICIDE REMOVAL IN TANGERINE CV. SAI NAM PHUENG

Abstract

Chlorpyrifos, a type of organophosphate insecticide, is widely used to destroy pests in the tangerine orchard to reduce the loss and maintain the quality of fruit. Consequently, the application of insecticides during production leads to the insecticide residues problem in tangerine that can be dangerous to human health. This study investigated the effect of ozone microbubbles (OMBs) on the removal of chlorpyrifos residues in the fruit. Tangerines were sprayed with chlorpyrifos solution at a concentration of 10 minutes. Then, they were treated with OMBs at different temperatures (15, 20 and 25 oC) for various exposing times (0, 10, 20, 30, 40, 50 and 60 minutes). Removal percentage of chlorpyrifos residues in tangerines was determined by gas chromatography-flame photometric detector (GC-FPD). The results showed that chlorpyrifos residues in tangerines were decreased at lower water temperature, especially at 15 oC resulting in the removal up to 81% after treating with OMBs for 30 minutes when compared to control (distilled water). After that, the fruits were stored at 25 oC for 7 days to determine quality changes. The percentage of weight loss, total soluble solids (TSS), titratable acidity (TA), disease incidence and ascorbic acid content in all treatments were not affected by OMBs. These results demonstrate that OMBs treatment at 15 oC is the most effective treatment for removing chlorpyrifos residues in tangerine and have no effects on the fruit quality.