Evaluación microbiológica y resistencia antimicrobiana de quesos frescos comercializados en el mercado privado de la ciudad de Macas

Abstract

The main objective of this research study was to determine the microbial load of dairy products (cheese) sold in the private market of the city of Macas to determine its food quality. Fresh cheese is a product that is mainly produced in an artisanal way. Its characteristic flavor is especially due to the presence of lactic acid bacteria, such as Lactococcus spp., Lactobacillus spp., Leuconostoc spp., and Enterococcus spp., which inhibit the growth of pathogenic microorganisms. The methodology implemented had a quantitative approach, a non-experimental design of transversal type was used because no independent variable was manipulated and it was carried out within the established time; the study population was the private market of the city of Macau, located in the province of Morona Santiago, where samples of fresh cheese were taken from 5 stalls, together with documentary research of the regulations NTE INEN 4, NTE INEN 1529-5 and NTE INEN 1529-13, as well as the review of documentation provided by MicroFast®. Using this methodology, the results obtained from the investigation were: mesophilic aerobic bacteria (4.15 x 107 CFU/mL); the number of Enterobacteriaceae (7.34 x 106 CFU/mL); Escherichia coli count (6.50 x 104 CFU/mL); Staphylococcus aureus count (1.44 x 106 CFU/mL), and the presumptive presence of Salmonella was also detected in the fresh cheese samples from stand no. 5. These results were compared with the permissible limits established in the NTE INEN 1528 Standard. The antibiogram showed resistance to ampicillin, tetracycline, and oxacillin. In this context, it is concluded that the values obtained from the microbial counts of the fresh cheese samples exceed the permissible microbiological limits so that the dairy products do not present acceptable food quality for population consumption.