PESTICIDE-RESIDUES IN RAISIN PROCESSING

The fate of the residues of benalaxyl, dimethoate, iprodione, metalaxy l, phosalone, procymidone, and vinclozolin in sunlight and oven raisin processing was studied. The drying process caused a fruit concentrati on factor of 4, while the decreases in residue with the two drying pro cesses were different for the different pesticides. In sunlight-drying the residue level in the raisins was identical to that in the fresh f ruits for benalaxyl, metalaxyl, and phosalone, whereas it was higher f or iprodione (1.6) and lower for vinclozolin and dimethoate (one-third and one-fifth, respectively). The oven-drying process was preceded by washing, which caused residue decreases for iprodione and procymidone of 57 and 41%, respectively, whereas no decrease was observed in all of the other pesticides. During oven-drying pesticide residues in rais ins with respect to fresh fruits showed an increase of 2.7 for phosalo ne, the same values for benalaxyl, metalaxyl, and procymidone, and low er values for vinclozolin and dimethoate. Sunlight-drying was more eff ective for phosalone and vinclozolin, whereas oven-drying was more eff ective for iprodione and procymidone, which was due to the washing eff ect rather than to dehydration. The experiments carried out with a mod el system showed that the decrease in dimethoate is attributable to he at, whereas in benalaxyl, procymidone, and phosalone it is due to codi stillation and in iprodione and metalaxyl to the combined action of he at and codistillation.