O Manual de métodos de análise microbiológica de alimentos e água é um manual de laboratório ilustrado contendo os métodos recomendados por órgãos internacionais (APHA, FDA, USDA, AOAC, ISO) aceitos pela Agência Nacional de Vigilância Sanitária (ANVISA). Cada capítulo traz uma revisão profunda e atualizada sobre o(s) microrganismo(s) tratado(s), incluindo posição taxonômica, mudanças na nomenclatura, características morfológicas e bioquímicas e epidemiologia. Oferece também comparações esquemáticas entre os métodos disponíveis, destacando suas diferenças e similaridades. A apresentação didática do passo a passo dos métodos em figuras esquemáticas permite uma rápida apreensão dos procedimentos, facilitando sua execução no dia a dia dos laboratórios.

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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.

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Bacteriophages specific for Leuconostoc oenos were isolated from four red wines undergoing malolactic fermentation in one winery. Bacteriophages were not found in samples of 16 other wines. The morphology of the phages was examined by electron microscopy. The phages did not lyse all strains of L. oenos, and susceptibility correlated to some extent with the colony morphology of the strain. Phage survived in wines at pH values greater than 3.5 but was inactivated in wines of lower pH and by the addition of sulfur dioxide or bentonite. Phage did not affect the growth of a sensitive strain of L. oenos in filter-sterilized wine.