Kinetics of growth and 3-methyl-1-butanol production by meat-borne, coagulase-negative staphylococci in view of sausage fermentation

Abstract

Five species of meat-borne, coagulase-negative staphylococci were screened for their in vitro production of 3-methyl-1-butanol. The highest production level was encountered for Staphylococcus sciuri alphaSG2, despite its poor growth. With respect to Staphylococcus species that are generally applied in sausage starter cultures, production of 3-methyl-1-butanol was higher with Staphylococcus xylosus 3PA6 than with Staphylococcus carnosus 833. Mathematical modelling was used to link the kinetics of 3-methyl-1-butanol production by S. xylosus 3PA6 and S. carnosus 833 in meat simulation medium to bacterial growth and environmental factors, in casu temperature and pH. The specific production rate of 3-methyl-1-butanol was about ten times higher for S. xylosus 3PA6 than for S. carnosus 833, indicating a higher production rate per amount of biomass. This explains the higher concentrations of 3-methyl-1-butanol in the medium with S. xylosus 3PA6, despite its poorer growth.