Diversity of staphylococcal species in pork and beef Kitoza

Abstract

International audienceKitoza is a traditional product from Madagascar manufactured either with strips of pork or beef meat. lt is an artisanal product manufactured in rural and urban regions. The first step of the process is salting with coarse salt mixed with spices and then either a drying or smoking step is carried out. Samples from pork and beef and both processes have been analysed. The microbiological analyses revealed the process allowed the selection of microorganisms with potential technological interest. Thus a high level of coagulase negative staphylococci (CNS) was noticed: between 5 to7 log CFU/g. These technological bacteria seemed well adapted to the two processes drying or smoking. 811 isolates of presumed CNS from Manitol Salt agar have been identified. Two approaches have been applied: a PCR multiplex as developed by Corbière Morot-Bizot et al. (2004. J. Appl. Microbial. 97, 1087-1094) or a staph array developed by Giammarinaro et al. (2005. J. Clin. Microbiol., 3673-3680) allowing the identification of 36 CNS species. A total of 9 species of CNS were identified in the Kitoza with 7 species for the beef and 8 for the pork meats. Staphylococcus saprophyticus was the dominant species in all the products and the major one in dried pork and beef smoked or dried. While in smoked pork, in addition of S. saprophyticus (50%), S. xy/osus (13%), S. equorum (15%), S. succinus (13%) and S. epidermidis (9%) were identified. This study highlighted that the process: salting and drying or smoking allowed the selection of coagulase negative staphylococci. These CNS are well described in the literature as contributing to the quality of meat products, with some species such as S. xylosus already used as starter cultures for the manufacture of meat products. This work was funded by EU, 7th Framework Programme, AFTER project (grant agreement 245025). (Résumé d'auteur