Microbiological quality of organic and conventional tomatoes

Abstract

In view of the need to inform the producers, dealers and consumers about the capability of the vegetables in being a vehicle for microorganisms, they should receive suitable hygienic and sanitary treatment. This paper aimed at evaluating the microbiological quality of organic and conventional tomatoes (Lycopersicon esculentum Mill.) commercialized in Curitiba city, southern Brazil. Eight samples of conventional tomatoes and four samples of organic tomatoes were collected from different sites. The microbiological analyses for detecting Salmonella spp and molds and yeasts were conducted according to the Compendium of Methods for Microbiological Examination of Foods. Total coliforms and Escherichia coli were analyzed by the PetrifilmTM methodology. The data were analyzed by variance analysis and Tukey tests. No Salmonella sp was isolated from 25 g of tomato samples. The total coliform counts ranged up to 1.4x103 CFU/g and Escherichia coli up to 2.3x102 CFU/g in conventional tomatoes. Yeasts and molds were found in conventional tomato samples up to 2.1x10, and up to 1.04 x 1012 CFU/g in organic tomato samples. This study clearly shows that the tomatoes ought to receive suitable hygienic and sanitary treatment before being commercialized.