Prevalência de patógenos e de microrganismos indicadores em leite informal e processado comercializados no Recôncavo da Bahia

Abstract

CAPÍTULO 1 = This study verified the presence of microorganisms contamination indicators, as well as the prevalence of Escherichia coli O157: H7, Listeria monocytogenes and Staphylococcus aureus in raw bovine milk samples, informal sale, milk and Ultra High Temperature (UHT), marketed in five cities of Bahia Reconcavo. For the study, they were analyzed 20 samples of raw milk and 35 samples of UHT milk, totaling 55 samples. The total count of psychrotrophic, mesophilic and thermophilic was performed by plating method in depth (Pour plate) among PCA (Count Agar standard). For quantification of total coliforms and E. coli was used for a culture medium selective agar base HiCrome ™ ECC. For identification of E. coli O157: H7 was used fast method of immune screening Singlepath®- E. coli O157. The population of S. aureus was obtained by the rapid method Petrifilm™ and the identification of L. monocytogenes was performed using the rapid method immunochromatographic Singlepath L'Mono®. From the analysis carried out in fresh milk has been shown that populations of mesophilic ranged from <1 to 9.0 log CFU / mL and its presence was confirmed in 80.95% of the samples, of which 76.47% were above the amount allowed by the legislation of 5.87 log CFU / mL (BRAZIL, 2011). The psychrotrophic microbes were found in 85.7% of samples, with populations of <1 to 9.0 log CFU / mL and thermophilic microorganisms were present in 14.28% with variation in populations of <1 to 6.0 log CFU / mL in the evaluated municipalities. There was presence of total coliforms in samples of 100% and 66.6% with E. coli populations ranging from <1 to 9.0 log CFU / ml and <1 to 8.0 log CFU / ml respectively. As for the results of analyzes in UHT milk, the populations of mesophilic ranged from <1 to 1.68 log CFU / ml and were present in 14.28% of the samples, none of which exceeded the amount allowed by 2 log legislation CFU / mL (BRAZIL, 1997). As for thermophilic and psychrotrophic microorganisms, these are <1 log CFU / mL. Total coliforms were present at 14.28% and 7.14% of E. coli in samples with populations ranging from 0.85 to 2.93 and 0.99 to 1.64 log CFU / mL respectively. Through microbiological analysis of milk in natura, the presence of Staphylococcus aureus in 76.19% of the samples was observed with population variance of <1 to 9.0 log CFU / mL. In the UHT milk samples showed values below <1 log CFU / mL. For the presence of E. coli O157: H7 in samples of milk fresh and UHT revealed as being the presence of 6.12% and 2.04%, respectively. As the analysis of Listeria monocytogenes, the result of all the milk samples studied were negative. Thus, these results highlight the importance of prohibiting the marketing of fresh milk by the competent bodies, as well as monitoring of UHT milk production steps, emphasizing the need to use good hygiene practices during its processing to marketing, in order to secure food production. CAPÍTULO 2 = Abstract – This study aimed to evaluate the sanitary quality and the presence of pathogens of informal bovine milk samples and processed. In the period from May to July 2015 were analyzed 55 samples acquired in five municipalities in the Bahia Recôncavo. The count of psychrotrophic, mesophilic and thermophilic was performed by plating method in depth among count standard agar and for the quantification of total coliforms and Escherichia coli was used through HiCrome ™ selective ECC. The identification of the species Escherichia coli O157: H7 was performed using the fast method Singlepath®- E. coli O157. The population of Staphylococcus aureus was estimated using Petrifilm ™ plates and identifying the presence of Listeria monocytogenes by means of Singlepath L'Mono® kit. It was evident that there was a greater contamination and presence of pathogens in the informal raw milk when compared to processed milk. However it was observed the presence of total coliform 14.28 % Escherichia coli 7.14 % and Escherichia coli O157: H7 2.04 % in the processed milk. Therefore, it stresses the importance of authorities in enforcement against the illegal sale of informal milk, as well as the monitoring of milk production steps processed until marketing.