Microbiological quality of organic and conventional vegetables sold in Brazil

Abstract

While searching for healthier diets, people became more attentive to organic produce. Yet, organic foods may be more susceptible to microbiological contamination because of the use of organic fertilizers, a possible source of pathogenic bacteria. In this study, 130 samples of different organic and conventional vegetable varieties sold in Brazil were analyzed for mesophilic aerobic bacteria, yeasts and molds, total coliforms, Escherichia coli and Salmonella spp. Most of the mesophilic aerobic bacteria counts in organic and conventional vegetables ranged from 6 to 7 log10 CFU/g; most of the yeasts and molds counts ranged from 5 to 6 log10 CFU/g and most of the total coliforms counts ranged from 4 to 5 log10 CFU/g. E. coli was found in 41.5% of the organic and 40.0% of the conventional vegetables, and most samples had counts ranging from 1 to 2 log10 CFU/g. Salmonella spp. was not found in any sample. Comparative analyses of the microbial counts of organic and conventional vegetables showed that some organic varieties have greater counts. However, the global results show that this is not a trend. These results indicate the need of good farming practices, and proper sanitization before consumption, to ensure food quality and safety.

Microbiological Quality of Organic and Conventional Leafy Vegetables

“…A range from 4 to >7 log CFU/g for yeasts and molds in organic and conventional vegetables was reported by the literature [26,27]. In the present work mean counts for yeasts and molds for each leafy vegetable were lower than 4 log CFU/g; however the samples were sanitized before analysis.…”

“…Some studies refer to the absence of Salmonella spp. in fresh vegetables from the Brazilian market [26,30]; however other researchers found the presence of Salmonella in a range from 0.7 to 20% of the samples [7,28,31].…”

“…In some Brazilian studies, higher microbial counts were observed for organic vegetables [7,26,28,32] than for conventional ones. However, the microbial comparison of organic and conventional vegetables is controversial and depends on several factors including inadequately composted or raw animal manure and irrigation with bad quality water [7,8,33].…”

Genetic heterogeneity of Escherichia coli isolated from pasteurized milk in State of Paraná, Brazil

“…coli has been isolated from various foodstuffs, such as meat, vegetables, milk, and milk derivatives, which can serve as a vehicle for the transmission of diseases by food (Lee et al, 2009;Solomakos et al, 2009;Brooks et al, 2012;Maffei et al, 2013).…”

Fresh-Cut Produce: Comparasion Between Sanitation And Production Methods: Organic Versus Conventional

“…As for which is safer? Both contain known and potent risks to human health and much attention needs to be drawn on how to prevent or minimize them, especially microbiological contamination which is the most common (Forman and Silverstein, 2012;Maffei et al, 2013;Smith-Spangler et al, 2012;Magkos et al, 2006). FC are not a low risk choice.…”