Residues of pirimicarb and dichlofluanide in apple processing to juice and wine

The fate of the insecticide pirimicarb and the fungicide dichlofluanide applied under field conditions was studied during apple processing to cloudy and clear juices and to cider. An untreated control was compared with raw material from usual application of active substances upon needs and with a sample from overconcentrated spraying. The residues in the clear juices and ciders from all variants were below the determination limit of 5 mu g/kg. Pressing and clarification by fining and filtration are important reduction steps for residues. During apple processing, the highest residue levels were found in the pomace of the overconcentrated treated sample. For cloudy juices, no values are given. Because of an insufficient cleanup and matrix effects, the methods used here for residue analysis are not suitable for cloudy apple juices. Cloud particles from cloudy juices of the overconcentrated treated sample were isolated preparatively and subjected to residue analysis. It could be demonstrated, that pirimicarb is able to enrich in the particles.