Differences in the levels of pesticides, metals, sulphites and ochratoxin A between organically and conventionally produced wines.

Organic products are generally recognized to be healthier and safer than conventional products. However, the actual scientific data regarding the importance of organic production on particular contaminant/additive content of wines is scarce. This study aimed to evaluate contents of pesticides, metals, sulphites and ochratoxin A in organically (org) and conventionally (conv) produced wines from eleven locations in different winegrowing regions of Croatia. All wines contained significantly lower levels of residues as compared to the maximum limits (MLs) with the exception of excessive amounts of Cu and Zn in one sample. Pb and Mg were mainly significantly less represented in org wines. There were no significant differences in the content of sulphite or ochratoxin A between org and conv wines. Significantly lower total pesticide concentrations and average number of pesticides per sample were obtained in org wines. The majority of ochratoxin A positive wines were from conv wine producers.

Novel multiresidue method for determination of pesticides in red wine using gas chromatography-mass spectrometry and solid phase extraction.

A new multiresidue method was developed for determination of 25 pesticide residues in red wine by gas chromatography coupled to mass spectrometry with a single run of 23.63 min. Samples were extracted from wine with solid phase extraction using Oasis HLB. Mixture of methanol and water was used for rinsing, while acetonitrile and n-hexane were used as elution solvents. Method was validated according to SANCO/12571/2013 criteria in wide linearity range (limit of quantification - 400 µg L(-1)). Limits of quantification (LOQ) were well below 10 µg L(-1) for most pesticides and recoveries at 2×LOQ and 10×LOQ concentration levels were in range 70-120%. Precision, expressed as a relative standard deviation, was always under 14%. The method was applied to 32 red wine samples from Croatia. Pesticides were detected in 30 samples with a total of 15 pesticides found, 7 of which were at a high concentration.