Identificación de bacterias acidolácticas antagónicas de Salmonella enterica var. Typhimurium aisladas de queso artesanal

Abstract

For the safety in dairy products, some Mexican regulations  make different operations compulsory, one of them is  pasteurization; however, many of the genuine cheeses  could not be made under this operation, since in many  cases their characteristics of typicality and genuineness  are generated by the native microorganisms coming  from the so-called raw milk; therefore, the reason for this  research was the contribution of evidence that acidolactic  fermentation could be an alternative to pasteurization.  In order to achieve this, the objective was to identify in  genus and species some acidolactic bacteria native to a  genuine Mexican artisanal cheese that had an antagonistic  capacity against Salmonella enterica var. Typhimurium  and to study its technological characteristics. To achieve  this, strains of BAL in MRSA were isolated from a genuine  artisanal cheese, antagonism tests were performed on TSA  searching for those with some inhibitory effect against  salmonella. Subsequently, the genus and the species with  the greatest effect were identified and their technological  characteristics were studied. The research was performed  in the UA-Zootecnia livestock microbiology laboratory,  UACh, from March-June 2015. 11 strains of BAL with antagonistic activity were identified and the species  Lactococcus lactis subspecies cremoris and Leuconostoc  spp. were identified as the ones that had greater inhibition  effect. Having BAL in artisanal cheese with antogonic  activity against a pathogen such as salmonella provided  evidence that acidolactic fermentation is an alternative to  pasteurization.