The ability of the meat isolate Staphylococcus sciuri I20-1 to inhibit food-borne pathogens in view of its
application as a functional starter culture for the production of clean-label fermented meats was
investigated. The strain produced a heat-stable antibacterial compound of a proteinaceous nature that
was released following primary metabolite production kinetics. Its specific inhibitory spectrum included
different strains of Staphylococcus aureus and both vegetative cells and spores of Clostridium botulinum.
These two species pose potential biosafety hazards, in particular when producing fermented meats with
a mild pH and without added nitrate and nitrite salts. Up till now, starter-culture based strategies to
restrain S. aureus and C. botulinum have barely been explored in fermented meats, in contrast to the
frequently investigated use of antilisterial cultures of lactic acid bacteria. When added to a fermented
sausage model, S. sciuri I20-1 acted as a persistent culture throughout the fermentation process, during
which it was able to produce its antibacterial compound in situ. In co-culture experiments, an immediate
two-log inactivation of a S. aureus strain was found, even before production of the antibacterial compound
could be detected. This was probably due to an instant pH-driven desorption of the antibacterial
molecules from the producer cells when added to the meat batter. However, a sub-population of S. aureus
that was resistant to the antibacterial compound was able to grow out to the same final counts as in the
control experiment performed with a non-inhibitory strain of S. sciuri. This finding is indicative of the
potential pitfalls when extrapolating promising in vitro results to the true complexity of fermented food