Survival of Salmonella spp. in minced meat packaged under vacuum and modified atmosphere

Abstract The effect of different modified atmosphere packaging regimes on the behavior of Salmonella spp. on minced meat was studied. Minced meat was experimentally contaminated with a Salmonella spp. cocktail (S. Enteritidis, S. Typhimurium, S. Infantis and S. Arizonae), packaged under vacuum or modified atmosphere with initial headspaces containing 20%O2/50%CO2/30%N2 and 20%O2/30%CO2/50%N2) and stored at 3 ± 1 °C for 12 days. Samples were analyzed for Salmonella spp., viable and lactic acid bacteria count every third day. Salmonella spp. counts decreased during storage in all packaging types, with reductions of about 1.5 log CFU/g. A significant difference (p < 0.01) was noted between Salmonella spp. counts in meat packaged in vacuum and modified atmospheres, although there was no significant difference in Salmonella spp. count between meat packaged in 50%CO2, and meat packaged in 30%CO2. At the end of the study, there were significant differences (p < 0.01; p < 0.05) in total viable and lactic acid bacterial counts between meat packaged in vacuum and modified atmosphere, and the lowest counts were noted in meat packaged in modified atmosphere with 50%CO2.

Pesquisa de salmonella spp, staphilococcus aureus, coliformes totais e coliformes termotolerantes em carne moída comercializada no Município de Umuarama - Pr / Investigación de salmonella spp, staphylococcus aureus, coliformes totales y coliformes termotolerantes en carne molida comercializada en el Municipio de Umuarama - Pr / Salmonella spp, staphylococcus aureus, total coliforms and fecal coliforms in ground meat commercialized in Umuarama - Pr

Devido ao excesso de manipulação e a utilização de equipamentos e utensílios com higienização deficiente, a carne moída é um produto que se contamina facilmente, estando frequentemente envolvida nos surtos de doenças transmitidas por alimentos. Os objetivos deste trabalho foram detectar a contaminação por Salmonella spp, coliformes totais, coliformes termotolerantes e Staphilococcus aureus de carne moída bovina vendida no comércio de Umuarama, PR e comparar os resultados com a legislação vigente. Para tal fim, foram coletadas 10 amostras de carne bovina moída em estabelecimentos comerciais (supermercados e açougues). Neste estudo, 100% das amostras de carne moída apresentaram S. aureus e coliformes totais, 90% coliformes termotolerantes e em nenhuma amostra foi detectada a presença de Salmonella spp, estando em conformidade com a legislação vigente, embora represente risco para a saúde da população consumidora.

Due to excessive handling and use of equipment and utensils with poor sanitation, ground meat is a product that is easily contaminated. It is frequently involved in outbreaks of foodborne diseases. The objectives of this study were to detect the contamination by Salmonella spp, total coliforms, fecal coliforms and Staphylococcus aureus in ground meat commercialized in Umuarama, PR and compare the results with the current Brazilian legislation. Therefore, we collected 10 samples of ground meat from commercial establishments (supermarkets and butcher shops) in Umuarama. In this study, 100% of ground meat samples showed S. aureus, total coliforms. For fecal coliforms, 90% of samples were positive, and no sample was positive for the presence of Salmonella spp. The samples were in accordance to the current legislation, although they represent risks to the consumers? health.

Debido a exceso de manipulación y utilización de equipamientos y utensilios con higienización deficiente, la carne molida es un producto que se contamina fácilmente, estando a menudo involucrada en brotes de enfermedades transmitidas por alimentos. Esta investigación buscó detectar la contaminación por Salmonella spp, coliformes totales, coliformes termotolerantes y Staphylococcus aureus de carne molida bovina vendida en el comercio de Umuarama, PR y comparar los resultados con la legislación vigente. Para ello, se recogieron 10 muestras de carne molida bovina en establecimientos comerciales (supermercados y carnicerías). En este estudio, 100% de las muestras de carne molida bovina mostraron S. aureus y coliformes totales, 90% coliformes termotolerantes y en ninguna muestra fue positiva para la presencia de Salmonella spp cumpliendo con la legislación vigente, aunque representa riesgo a la salud de la población consumidora.

Contaminação microbiana em carne moída de açougues da cidade de Santa Maria, RS, Brasil / Microbial contamination in minced meat of butcher shops of Santa Maria city, RS, Brazil

Foram coletadas aleatoriamente, 10 amostras de carne moída bovina em açougues da cidade de Santa Maria, RS, para determinar a presença de microorganismos totais, coliformes e Staphylococcus aureus. Respectivamente, usou-se os meios ágar para contagem total (PCA), ágar cristal violeta vermelho neutro bile e ágar bairdparker. Na contagem de microorganismos totais, 60% das amostras apresentaram entre 1,7 a 8,8 x 10(4) uFC/g de carne moída. Para Coliformes, 20% das amostras apresentaram um número menor que 1,0 x 10² uFc/g, 40% entre 1,0 a 3,2 x 10³ uFC/g, 30% entre 3,7 a 9,6 x 10(4) uFC/g e em 10% houve acidente laboratorial. Para Staphylococcus aureus, 100% das amostras resultaram positivas, sendo 50% entre 1,0 a 4,0 x 10³ uFC/g, 40% entre 1,3 a 2,8 x 10(4) e 10% entre 1,5 a 4,0 x 10(5) uFC/g de carne moída.

Ten samples of minced meat beef were collected in butcher shops of Santa Maria City, RS, Brazil, to determine the presence of total microorganism, total coliforms and Staphylococcus aureus. Respectively, PCA (Plate Counter Ágar), violet cristal red neutral bile and baird parker ágar was used. In the ágar plate counter for total microorganism. 60% of the samples presented a number between 1.7 a 8.8 x 10(4) CFU/g of minced meat. For Coliforms, 20% of the samples presented a number less than 1.0 x 10² C FU/g, 40% were among 1.0 and 3.2 x 10³ CFU/g, 30% between 3.7 to 9.6 x 10(4) CFU/g and in 10% had laboratory acidental. For Staphylococcus aureus, 100% of the samples turns positives with 50% of that between 1.0 a 4.0 x 10³ CFU/g, 40% among 1.3 to 2.8 x 10(4) CFU/g and 10% among 1.5 to 4.0 x 10(5) CFU/g of minced meat beef.