Selection of Staphylococcus carnosus strains based on in vitro analysis of technologically relevant physiological activities

The focus of this study was the taxonomic identification of a collection of 40 Staphylococcus carnosus strains to the species, subspecies and strain level. These strains were screened for physiological activities suitable for their use as starter cultures, in particular as starter cultures for the processing of raw ham. Consequently, the strains were tested for their ability to grow in Brain Heart Infusion broth at different NaCl and NaNO2 concentrations. We found that most of the S. carnosus strains tested were able to grow at NaCl concentrations of up to 150 g l(-1) and at NaNO2 concentrations of up to 400 mg l(-1). Essential metabolic activities, such as nitrate reduction, proteolysis and lipolysis, were analysed in vitro. Three S. carnosus subsp. carnosus strains produced > 0.6 mol NO2 per 1.0 x 10(7) colony forming units. Twenty-six S. carnosus strains showed proteolytic activity on calcium caseinate agar, and one S. carnosus subsp. utilis strain showed activity on agar supplemented with sarcoplasmic proteins. Lipolytic activity was found in 34 strains. Of these 40 S. carnosus strains four were found to fulfil the multiple metabolic requirements necessary for their use in industrial meat fermentation processes.