Microbiological analysis and Nitrite and Nitrate content in cheese

Abstract

Objective: This study aimed to analyze the amount of thermotolerant coliforms, Salmonella, Staphylococcus coagulase positve, nitrite and nitrate content, pH and water activity, in cheese type prato and colonial, with municipal and state inspection from Taquari Valley - RS. Materials and Methods: The residual levels of nitrates and nitrites, pH and water activity of the samples were performed using the offical analytical methodologies under the Normative Instruction No. 20, dated July 21, 1999 of the Ministry of Agriculture, Livestock and Supply. Microbiological analyzes were performed in a certified laboratory in the Ministry of Agriculture. Results: Of the 24 cheese samples 18.2% had thermotolerant coliforms above the law with Municipal Inspection and 61.5% of the samples with the State Inspection. The Staphylococcus coagulase positive was not found in any of the samples with Municipal Inspection, and 46.2% with State Inspection. Salmonella was not found in any sample. The levels of nitrites and nitrates were presented respectively by 33.3% and 100% above the upper limit of the total samples. Conclusion: It was concluded that the cheese samples produced with state inspection results showed more concern regarding contamination by Staphylococci coagulase positve and thermotolerant coliforms compared with Municipal Inspection. In this study, it was concluded, therefore, that all the samples showed concentrations above recommended for legislation to nitrite and over one third are not presented as relative concentration of nitrate. In relation to water activity and pH, most of the samples met according to the criteria of the legislation.