Evaluación de la calidad fisicoquímica y microbiológica de la leche cruda almacenada en centros de acopio de la provincia de Chimborazo

Abstract

The objective of this research work was to evaluate the physicochemical and microbiological quality of raw milk stored in three collection centers (CC) located in Guano Canton, province of Chimborazo. A checklist of the sanitary hygienic conditions issued by Agrocalidad applied to the collection centers, the transport that delivers the milk and the one that takes the product to the Dairy Industry was used. Duplicate milk samples were taken from the storage tank in each CC for three days to perform the physicochemical analyzes using the LACTOSCAN equipment and rapid tests. The count of health quality indicator microorganisms was carried out: Enterobacteria, Staphylococcus aureus, mesophilic aerobes, molds and yeasts, and the lactic acid bacteria count using the relevant Ecuadorian technical standards. The genus and species of bacteria isolated from Enterobacteria cultures were identified through Gram staining and biochemical tests. The results show that milk quality is affected by the lack of infrastructure and hygiene in the CAs, and by the low level of compliance with the transport delivered by the milk to the center. The results regarding the physicochemical analysis showed that pH and cryoscopic point were outside the permissible limits. The results of the count of Enterobacterias, mesophilic aerobes, mold and yeast and Staphylococcus aureus, exceeded the values in log 10UF/g 5.11; 6.18, 4.48; 3 to 4, respectively. The genus and species identified Enterobacteria were inactive Escherichia coli and Klehsiella pneumomae. In conclusion, raw milk has low microbiological quality, attributed to inadequate handling conditions. More research on the health status of animals is recommended, especially related to mastitis and the importance of the effect of containers to determine their contribution to microbial quality.