Estudio de las propiedades tecnológicas de bacterias aisladas de leche maternaaplicación para el desarrollo de alimentos funcionales

Resum

In this work, a variety of biochemical properties of Enterococcus faecium LJx4, which had been isolated from breast milk, were analyzed. Its acidifying capacity and proteolytic activity were low but, in contrast, remarkable peptidase and esterase activities were observed. Ethanol and 3-hydroxy-2-butanone were the most abundant volatile compounds found in experimental model cheese manufactured with E. faecium LJx4. This strain inhibited the growth of several Listeria monocytogenes and Listeria innocua strains in vitro. Model fermented milk and cheeses were manufactured from milk inoculated or not with L. innocua SA1 (2.5-3 log10 colony forming units mL-1) using E. faecium LJx4 or Lactococcus lactis ESI 153 as starter cultures. Although E. faecium LJx4 controlled Listeria growth in both dairy models, it led to lower reduction in Listeria counts when it was compared with L. lactis ESI 153. In conclusion, our results indicate that E. faecium LJx4 could be useful as adjunct and/or bioprotective culture in dairy products