Caracterização e estudo do perfil tecnológico de bactérias ácido láticas isoladas de queijos tipo Minas artesanais e leite cru

Abstract

The objective to develop a lactic culture to elaborate a cheese with regional characteristics, acid lactic bacterias were isolated and identified from cheese and milk samples and evaluated to the enzymatic activity, common clinical antibiotic resistance, antagonistic activity and acidification capacity. The genders Enterococcus, Lactococcus, Lactobacillus, Streptococcus and Pediococcus were identified by the Polymerase Chain Reaction analysis. The isolates Bal 3 (Enterococcus sp) (37°C) and Bal11 (Enterococcus durans) (20°C) presented the best enzymatic activity to tween 20, however, none of the isolates presented enzymatic activity to olive oil, neither to milk casein. All isolates were sensitive to vancomycin and resistant to streptomycin and only three isolates showed resistance to gentamicin. The most part of the studied BAL were capable to inhibit the pathogens growth as enteropathogenic E. coli, Salmonella enteritides ATCC 13076, Listeria innocua CLIP 12612 and Listeria monocytogenes CDC 4555, with the cultures from genders Enterococcus and Lactobacillus which presented better antagonistic activity. The S. aureus, E. faecalis and E. faecium were not inhibited by the tested isolates. All the isolates reduced the pH values and produced lactic acid at 20°C and 37°C with significant difference to all periods evaluated (6, 12, 24 and 48 hours). By means of the stated, it is possible to conclude that the isolated BAL has the potential use as a secondary culture to dairy products industry.