Isolation and technological properties of coagulase negative staphylococci from fermented sausages of Southern Italy

Abstract

The aims of this study were to characterize the population of Micrococcaceae in different types of fermented sausages of Southern Italy and to determine the technological properties of Staphylococcus strains in order to evaluate the suitability of selected strains as starter cultures in the processing of dry fermented pork sausages. Ninety-six strains were studied to evaluate nitrate reductase, proteolytic, lipolytic and antioxidant activities as well as growth ability at different temperatures, pH's and NaCl concentrations. All the strains were classified as Staphylococcus except for one isolate assigned to Kocuria spp. The species most often isolated were S. saprophyticus, S. xylosus and S. equorum, although they were not equally distributed within the different sausages. Other species isolated were, in descending order of abundance, S. succinus, S. warneri, S. lentus, S. vitulus, S. pasteuri, S. epidermidis, and S. haemolyticus. In general, the S. xylosus strains exhibited the best technological properties that would make them eligible as good starter cultures for fermented meat products. However, strains belonging to other species also showed good technological properties. Finally, all strains grew at 10, 15 and 20 °C, in the presence of 10% and 15% of NaCl and at pH 5.0 and 5.5. The results showed that it is possible to formulate a broad variety of staphylococcal starter cultures, adaptable to different technological conditions and sausage manufacture practices.