Caracterização físico-química e microbiológica do queijo minas artesanal na região de Uberlândia-MG

Abstract

This study aimed to characterize the Minas Artesanal cheese produced in Uberlândia and check the minimum maturation period in which they reached the microbiological standards required by law. The physico-chemical characteristics (humidity, fat, fat in dry extract, acidity, sodium chloride, protein, ash and foreign material) and microbiological (total coliforms, E. coli, yeasts and molds, positive coagulase Staphylococcus, Salmonella spp were evaluated., and Listeria monocytogenes) of cheeses produced in rainy and dry season for up to 26 days of maturation, before and after the best practices training. In addition, to assess the hygienic-sanitary conditions in which the cheeses were produced was also performed analyzes of hands, equipment, water potability, pingo and milk. The strains identified as positive coagulase Staphylococcus were tested for antimicrobial susceptibility. We observed a large amount of foreign material in cheese as hairs, insect fragments and particles not identified, featuring none of the properties were in accordance with the standards of good manufacturing practices. The maturation period and % of cheeses humidity influenced (p <0.05) to total coliform and E. coli reduces over time, whereas for positive coagulase Staphylococcus there was no significant influence. We defined that microbiological parameters required by law have been achieved on day 26 of maturation. Listeria monocytogenes was not found in all samples and only one sample analyzed on the first day of maturation was positive for Salmonella spp. The maturation influenced the increase of the average values of chloride, protein, acidity, ash and fat and decreased humidity (p <0.05) in both cheeses produced in the dry and rainy seasons. All samples of water, pingo, milk and equipment presented counts for coliform and in hands were identified positive coagulase Staphylococcus. Among 77 strains isolated from coagulase positive cheeses, 48 (62.34%) were resistant to penicillin G and 42 (54.55%) to ampicillin, while for the other antibiotics tested, the resistance was lower, 1 (1.3%) to gentamicin, 25 (32.47%) for Oxacillin, 12 (15.58%) for Azithromycin, 6 (7.79%) for Clindamycin, 1 (1.3%) to Sulphazotrim and 14 (18.18%) to Erythromycin. Antimicrobial resistance to oxacillin and ampicillin was influenced by aging time (p <0.05). The sizes of inhibition zones for the antibiotic oxacillin decreased throughout maturation, but increased when ampicillin was tested. We conclude that 26 days are required for the maturation of cheeses meet the microbiological standards recommended by the legislation, but only this criterion is not sufficient to ensure safety in the consumption of food, requiring strict control and supervision in all production stages.