Implementación de una guía técnica para la pasteurización de leche y evaluación de su efectividad mediante análisis microbiológico en la planta de lácteos “VIGLAC” ubicada en el cantón Tambo

Abstract

Pasteurization is a thermal process is to reduce the microbial load to safe levels and/ or the total destruction of pathogenic microorganisms that may be present in milk or other foodstuff, guaranteeing safety and avoiding diseases transmitted by food (ETAS). Based on a pilot study conducted at the VIGLAC Dairy Plant, it was determined that the pasteurization process at 72 ° C for 4 seconds was deficient, given that the microbial load present in the pasteurized product exceeded the values of mesophilic aerobes, Total coliforms and Eschericha coli allowed by the NTE INEN 10: 2012. Observing this reality, it was proposed to structure and implement the Technical Guide for milk pasteurization. To test its effectiveness, a new test was carried out, taking samples of raw milk (25) and samples of pasteurized milk (360) for a period of 5 weeks. The analysis of the samples shows that the application of a pasteurization process accomplished at 72 ° C for 20 seconds reduces the bacterial load to an average value of 5,8 x101 UFC/cm3 (σ = 9,11 x100) for mesophilic aerobes and <1 UFC/cm3 (σ =  0,9) for total coliforms / E.coli. In addition, kinetic equation of bacterial inactivation and the calculation logarithmic reductions were applied, same that corroborate the time and temperature used in pasteurization described in the Technical Guide were adequate to reduce the bacterial to what is indicated in the norm in force in Ecuador.