Avaliação microbiológica de hortaliças orgânicas, alface (Lactuca sativa) e rúcula (Eruca sativa), comercializadas na região metropolitana de Cuiabá-MT

Abstract

The production of organic food is based on techniques that dispense with the use of inputs such as synthetic pesticides, chemical fertilizers, veterinary drugs, genetically modified organisms, preservatives, additives and irradiation. However, there is the use of organic matter as a form of fertilization and soil fertilization, using vegetable compost and animal waste such as cattle, poultry and swine manure; chicken litter, which may be contaminated with intestinal parasites, viruses and pathogenic bacteria such as Escherichia coli and Salmonella spp., these being indicators of poor hygienic-sanitary quality during some stage of the production chain. This study aimed to verify the presence of pathogenic indicator microorganisms (thermotolerant coliforms and Salmonella spp.) in organic lettuce (Lactuca sativa) and organic arugula (Eruca sativa) produced and marketed in the metropolitan region of Cuiabá- MT, as well as to identify the main sources of microbiological contamination in this production system. For this, 10 samples of each vegetable (lettuce and arugula) were collected in a farm and supermarket, in addition to 5 samples of each agricultural adjuvant (irrigation water, organic vegetable and animal fertilizers). Microbiological analyses of organic leaves were performed according to APHA (American Public Health Association) methodologies. For the determination of total coliforms and thermotolerant coliforms (ISO 7251:2005) and Salmonella spp. (ISO 6579: 2002). Of the total samples analyzed, all showed absence of Salmonella spp., however, thermotolerant coliform counts above the maximum acceptable limit of the Commission for Microbiological Specifications for Food (ICMSF) were observed in 90% (9/10) of the arugula samples and 50% (5/10) of lettuce samples on the farm, organic animal and vegetable fertilizers 60% (6/10), irrigation water 40% (2/5). The results suggest that the microbiological quality of vegetables, fertilizers and irrigation water in the field are not satisfactory, which indicates a deficit in good agricultural practices. The samples analyzed in the supermarket showed low counts of Coliforms at 45 °C, being 20% (2/10) and 10% (1/10) in the arugula and organic lettuce samples, respectively. These results can be justified by the precleaning in the field with running water, removal of lettuce roots, spraying of water with a hyperchlorinated solution and storage in a refrigerated vegetable exhibitor in the supermarket. However, it is important to highlight that if the correct hygiene of these vegetables is not adopted before consumption, the consumer public of these products is at risk of contamination by pathogenic microorganisms.