The objectives of this work were to verify the capability of Staphylococcus aureus of forming bio-film on stainless steel and glass surfaces; to evaluate the efficiency of sodium dichloroisocyanurate, hydrogen peroxide and peracetic acid in inactivating Staphylococcus aureus cells adhered onto these surfaces; and to visualize biofilm development by scanning electron microscopy before and after sanitizer treatment. The surfaces studied consisted of 10x20mm chips immersed in Petri dishes containing BHI broth inoculated with S. aureus ATCC 25923. Biofilm formation was observed after 15-day incubation, when the cells were removed using the swab technique, followed by Baird Parker agar plating. Also, the efficiency of the chemical sanitizers on the chip surfaces was tested and the non-removed cells were counted on the Baird-Parker agar. After biofilm formation and use of sanitizers, the chips were respectively observed by scanning electronic microscopy following a pre-existing protocol. The obtained results showed biofilm formation on both surfaces, with bacterial count in the order of 10 7 CFU/cm 2 on and 10 8 CFU/cm 2 on stainless steel and glass surfaces, respectively. Peracetic acid was the most efficient in removing adhered cells, presenting 5.26 and 4.5 decimal reduction for adhered cells on stainless steel and glass surfaces, respectively.

RESUMOCom o presente trabalho, objetivou-se avaliar a qualidade higiênico-sanitária de lingüiças tipo frescal, em função do potencial risco que estes produtos representam para a saúde pública. Para a condução de tal pesquisa, amostras foram aleatoriamente coletadas no município de Três Corações (n=20) e Lavras (n=20), ambos situados no Estado de Minas Gerais. As análises microbiológicas, conduzidas de acordo com o ICMSF (1982), constaram da enumeração de coliformes totais e termotolerantes (colimetria), quantificação e identificação bioquímica de Staphylococcus coagulase positiva e Salmonella spp. Não foi detectada a presença de Salmonella spp. em nenhuma das amostras. Os valores para contaminação por coliformes termotolerantes encontraram-se dentro do intervalo de 10 1 a 10 4 NMP/g. Em 14% das 40 amostras analisadas foi detectado Staphylococcus coagulase positiva acima do limite estabelecido pela legislação vigente. Pelos valores encontrados, as lingüiças analisadas não são produzidas dentro de padrões de higiene satisfatórios, sendo um potencial causador de toxinoses e infecções alimentares aos consumidores. Termos para indexação:Lingüiça tipo frescal, microbiologia, qualidade. ABSTRACTThe aim of this work was to evaluate the microbial quality of sausage in function of the potential involvement of these products in public health questions. Samples were randomly collected in Três Corações (n=20) and Lavras (n=20), both cities of Minas Gerais, Brazil. Microbiological analysis (ICMSF, 1982) were conduced to quantify, isolate and identify coliforms, Staphylococcus aureus positive coagulase and Salmonella spp. Salmonella spp was not found in none of samples. Counts of coliforms were between 10 1 to 10 4 MPN/g. Counts Staphylococcus positive coagulase were above the limit established by food legislation in 14% of the samples. In function of values found in this research sausages analyzed were elaborated under inappropriated conditions of hygiene and may represent risks to consumers.

Desenvolveu-se este estudo com a finalidade de verificar alguns microrganismos indicadores de contaminação e deterioradores em ricota cremosa durante sua vida de prateleira. No controle microbiológico do produto observaram-se os seguintes resultados: < 0,3 NMP/g de coliformes, <1,0 x 10² UFC/g de Staphylococcus produtores de coagulase e contagem total de aeróbios mesófilos entre 2,0 x 10² e 2,45 x 10(4) UFC/g. As contagens de aeróbios mesófilos diminuíram com o tempo de armazenamento, já que as amostras foram mantidas durante vinte dias sob temperatura de geladeira (7ºC). Os resultados do controle microbiológico da ricota cremosa demonstraram condições higiênico-sanitárias satisfatórias.

Shiitake mushroom consumption is increasing in Brazil. In addition to the implementation of new production methods, it is also important to increase productivity, quality and reduce production costs. In this study, six commercial Lentinula edodes strains were characterized for genetic diversity (rep-PCR analysis) and mushroom production (yield, number and weight of individual mushrooms) using different substrates and cultural conditions. All strains showed genetic differences by repetitive element palindromic based-polymerase chain reaction (rep-PCR). The richest substrate resulted in the greatest production under both environmental conditions. Strains LE4 and LE6 produced the majority of their mushrooms earlier than the other strains. The highest number of mushrooms was observed in the LE6 strain while the highest weights of individual mushrooms were observed in the LE4 strain. Controlled environmental conditions resulted in superior production for all strains, except for LE4, which had empirically greater yield in the semi-controlled environmental condition.

The composition and genetic diversity of fungal populations during phase II of compost production for the cultivation of Agaricus subrufescens was determined using culture-dependent and -independent methods on days 3, 6, 10, 12, and 14 of phase II composting. The isolates were morphologically characterized and subsequently analyzed using repetitive extragenic palindromic sequences (rep-PCR), and the intergenic region was sequenced to genetically identify the isolates. Changes on in the filamentous fungi population were analyzed using denaturing gradient gel electrophoresis (DGGE), and the resulting bands were sequenced. The population did not significantly change from day 3 to 10 (2.55 x 10(5) -6 x 10(5) CFU g(-1)), and maximum counts on day 14 of phase II composting (6.92 log CFU g(-1)). In the morphological characterization, Scytalidium thermophilum, Thermomyces lanuginosus, and Thermomyces ibadanensis were the most abundant identified species. The 26 most abundant isolates identified by morphological analysis were characterized using rep-PCR. A significant amount of genetic diversity was detected among the isolates of all three studied species. Based on the DGGE analysis, the diversity of the fungi was reduced during phase II composting, and S. thermophilum was the predominant species identified throughout the entire process. Thus, this study presents the first report of the involvement of T. ibadanensis in the production of compost for Agaricus mushroom cultivation.