Análisis de la contaminación microbiológica por patógenos alimentarios en quesos frescos sin marca en los mercados de la zona urbana del cantón Ambato

Abstract

The food pathogens Salmonella spp. and Escherichia coli have been linked to foodborne diseases (FBD). The sources of contamination are mainly food handlers at different stages in the production process, food transportation, storage at the point of sale, cold chain failures and poor hygiene. For this research, 24 unbranded fresh cheeses were analyzed in the 8 markets of the urban area of Ambato. At three points in time, day 0, day 7 and day 15. The cheeses were stored refrigerated for 7 and 15 days. For the analysis of Salmonella spp., the methodology NTE INEN 1529-15 was used, this method consists of the application of the following stages: Pre-enrichment, selective enrichment, plate seeding and biochemical identification. On the other hand, for the identification of Escherichia coli, the AOAC 991.14 methodology was used, which consists of sowing by dilutions in petrifilm EC plates. The conclusion was that 25 percent of the markets met optimal storage conditions. On the other hand, none of the samples analyzed complied with the maximum permissible limit for Escherichia coli. However, those samples that had proper storage had no E. coli on day 0. On day 15, 50 percent of the markets had Escherichia coli. On the other hand, the Salmonella spp. analysis was negative in all 24 samples, complying with NTE INEN 1528:2012.