Anti-Escherichia coli effect of Hibiscus sabdariffa L. in a meat model

Abstract Hibiscus sabdariffa L. is used in traditional medicine because of its bioactive properties, such as antioxidant and antibacterial. Escherichia coli is a Gram-negative bacteria and as an indicator of contamination in food. The aim of this work was to evaluate the anti-Escherichia coli effect and the change in pH on the control of aerobic mesophilic microorganisms, using hydroethanolic extract of H. sabdariffa L. in different concentrations in a meat model, verifying its potential as food additive for microbiological stability on ground beef during cooling storage. For the preparation of the treatments, the meat experimental units were elaborated with different concentrations of the vegetal extract (5, 10, 15 and 20%), ground beef and contaminated with E. coli. For pH evaluation, the meat experimental units were added different percentages of hydroethanolic extract. The H. sabdariffa L. antibacterial action reduced two logarithmic levels in practically all treatments. The best pH result was obtained in the meat containing 30% of the extract. The hydroethanolic extracts of Hibiscus sabdariffa L. showed anti-Escherichia coli activity in the presence of refrigerated ground beef. Analyzing the pH results and the count of aerobic mesophilic bacteria, it is possible this extract to be used as a natural food additive.

Qualidade microbiológica de queijo ricota comercializado na região Noroeste do Rio Grande do Sul / Microbiological quality of ricotta cheese marketed in Rio Grande do Sul the Northwest region

O objetivo deste estudo foi analisar a qualidade microbiológica de quatro marcas de ricota comercializadas na região Noroeste do Rio Grande do Sul, sendo analisados cinco lotes de cada marca. Avaliou-se a presença de coliformes totais e termotolerantes, Escherichia coli, Staphylococcus coagulase positiva, bolores, leveduras, e de Salmonella spp., além da temperatura de armazenamento e pH. Constatou-se que, 85% das amostras apresentaram contaminação por coliformes totais e 75% por coliformes legislação brasileira, RDC nº 12 de 2001. Leveduras foram encontradas em 90% das amostras e Staphylococcus coagulase positiva e Salmonella spp. não foram detectados. 80% das amostras estavam armazenadas em temperaturas superiores a 8ºC, favorecendo o desenvolvimento microbiano e 25% apresentaram valores de pH ácido. Os resultados obtidos indicaram haver falhas no processamento que, quando aliadas ao mau armazenamento, promovem o desenvolvimento de micro-organismos, os quais aceleram a deterioração do produto e representam sério risco à saúde do consumidor. Maior controle por parte das indústrias e fiscalização pelos órgãos competentes são necessários, a fim de garantir o consumo de ricotas de qualidade.

The aim of this study was to analyze the microbiological quality of four trademarks of ricotta commercialized in the northwestern of Rio Grande do Sul The samples (five lots of each brand) were evaluated for the total and thermotolerant coliforms, Escherichia coli, coagulase-positive Staphylococcus, yeasts and molds, Salmonella, storage temperature and pH. Results showed contamination by total and thermotolerant coliforms in 85% and 75% of the samples, respectively, and 50% were inappropriate for human consumption according to the Brazilian legislation (RDC nº 12, 2001). Yeasts were found in 90% of samples, but coagulase-positive Staphylococcus and Salmonella were not identified. 80% of the samples were stored at temperatures above 8°C favoring microbial growth and 25% showed acid pH values, indicating the presence of fermenting microorganisms. The results showed flaws in the ricotta in the processing environment that, allied to inadequate storage at sale points, promote the growth of microorganisms and can accelerate the deterioration of the product, besides it is a risk to consumer health. Greater control by industries and supervision by the competent agencies are required to ensure the quality of ricotta consumption.

Microbiological quality of ricotta cheese marketed in Rio Grande do Sul the Northwest region / Qualidade microbiológica de queijo ricota comercializado na região Noroeste do Rio Grande do Sul

The aim of this study was to analyze the microbiological quality of four trademarks of ricotta commercialized in the northwestern of Rio Grande do Sul The samples (five lots of each brand) were evaluated for the total and thermotolerant coliforms, Escherichia coli, coagulase-positive Staphylococcus, yeasts and molds, Salmonella, storage temperature and pH. Results showed contamination by total and thermotolerant coliforms in 85% and 75% of the samples, respectively, and 50% were inappropriate for human consumption according to the Brazilian legislation (RDC nº 12, 2001). Yeasts were found in 90% of samples, but coagulase-positive Staphylococcus and Salmonella were not identified. 80% of the samples were stored at temperatures above 8C favoring microbial growth and 25% showed acid pH values, indicating the presence of fermenting microorganisms. The results showed flaws in the ricotta in the processing environment that, allied to inadequate storage at sale points, promote the growth of microorganisms and can accelerate the deterioration of the product, besides it is a risk to consumer health. Greater control by industries and supervision by the competent agencies are required to ensure the quality of ricotta consumption.(AU)

O objetivo deste estudo foi analisar a qualidade microbiológica de quatro marcas de ricota comercializadas na região Noroeste do Rio Grande do Sul, sendo analisados cinco lotes de cada marca. Avaliou-se a presença de coliformes totais e termotolerantes, Escherichia coli, Staphylococcus coagulase positiva, bolores, leveduras, e de Salmonella spp., além da temperatura de armazenamento e pH. Constatou-se que, 85% das amostras apresentaram contaminação por coliformes totais e 75% por coliformes legislação brasileira, RDC nº 12 de 2001. Leveduras foram encontradas em 90% das amostras e Staphylococcus coagulase positiva e Salmonella spp. não foram detectados. 80% das amostras estavam armazenadas em temperaturas superiores a 8ºC, favorecendo o desenvolvimento microbiano e 25% apresentaram valores de pH ácido. Os resultados obtidos indicaram haver falhas no processamento que, quando aliadas ao mau armazenamento, promovem o desenvolvimento de micro-organismos, os quais aceleram a deterioração do produto e representam sério risco à saúde do consumidor. Maior controle por parte das indústrias e fiscalização pelos órgãos competentes são necessários, a fim de garantir o consumo de ricotas de qualidade.(AU)

Avaliação físico-química e microbiológica de salames artesanais / Physical-chemical and microbiological handmade salamis

Entende-se por salame, o produto cárneo obtido de carne suína ou bovina, adicionado de toucinho, ingredientes, embutidos em envoltórios naturais e/ou artificiais, curado, fermentado, maturado, defumado ou não dessecado. Este trabalho teve por objetivo analisar micro-organismos indicadores, através da análise de coliformes totais e fecais, verificação do pH e atividade de água em salames artes anais comercializados na região da serra gaúcha. Dentre as amostras analisadas houve contaminação tanto para coliformes totais quanto para fecais, todas, porém, dentro dos níveis aceitáveis pela RDC 12. Na verificação de atividade de água somente três amostras demonstraram não estar nos limites que a legislação permite de até 0,92, já na medição de pH foram encontrados valores normais para produtos cárneos. Embora fabricados e comercializados em condições higienicossanitárias, por vezes, questionáveis, a maioria das amostras de salames oriundos da região da serra gaúcha, avaliados, estavam aptas para consumo, considerando os padrões microbiológicos e físico-químicos analisados. (AU)

It is understood as salami, the meat eating product obtained from swine or bovine, lard added, ingredients, embedded on natural wraps and/or artificial, cured, fermented, matured, smoked or not dried. The study has as objective to analyze indicators microorganisms, trough analysis of total fecal coliforms, verification of pH and activity of water in artisanal salami commercialized in mountain region of Rio Grande do Sul. Among the analyzed samples it has contamination as total as well as fecal coliforms, all of them, however inside accepted levels by RDC 12. On verification of water activity only three samples not being inside legal limits of Max 0.92, on pH was found values normality for eating products. Although manufactured and commercialized in hygiene and sanitary conditions, some times, questionable, the most of the salami sample from mountain region of Rio Grande do Sul, evaluated, was able to consume considering the standard microbiological and physic-chemical analysis. (AU)