Antimicrobial activity of potential starter cultures towards food pathogens for the production of fermented meats without nitrate or nitrite

The ability of two coagulase-negative staphylococci (Staphylococcus sciuri I20-1 and Staphylococcus sciuri VT-S8-8) to inhibit food-borne pathogens in view of their application as functional starter cultures for the production of clean-label fermented meats was investigated. Both strains were active towards Clostridium botulinum and Staphylococcus aureus, two pathogens that may represent a risk in fermented meats prepared without added nitrate and nitrite. The inhibitory compounds were heat-stable, proteinaceous, and displayed primary metabolite kinetics, indicating a bacteriocin-like nature. During fermentation in meat models, the competitiveness of S. sciuri I20-1 and VT-S8-8 and production of their bacteriocins within the meat was confirmed. In meat models that also contained a rifampicin-resistant S. aureus strain, an immediate two-log reduction of the latter pathogen was found upon the inoculation of S. sciuri I20-1. This was probably due to an instant desorption of bacteriocin molecules from the added producer cells. Yet, a bacteriocin-resistant sub-population was found that grew out to the same final levels as in the control experiment, underlining the need to verify resistance phenomena when applying starter cultures that produce bacteriocin molecules.

ISBN:2-7380-1379-1

Jaar van publicatie:2015

Trefwoorden:starter cultures, fermented meat, nitrate, nitrite