Molecular and physiological characterization of natural microbial communities isolated from a traditional Southern Italian processed sausage.

The development of the natural microbial populations during traditional processing of the "Salame di Senise", a typical little known sausage produced in the South of Italy, was investigated by using molecular and physiological techniques for taxonomic identification and technological characterization of strains. The application of RAPD-PCR over more than 90 colonies made it possible to isolate 18 bacterial and two yeast biotypes identified by partial rDNA sequencing as belonging mainly to three species of Bacillus, three species of Lactobacillus, three species of Staphylococcus and Debaryomyces hansenii. The physiological analyses revealed that the isolates belonging to Lactobacillus genus were the most acidifying, whereas Staphylococcus strains did not develop significant proteolytic and lipolytic activities. Interestingly, some Bacillus strains produced the highest values of proteolytic and lipolytic activities. The results for the technological properties of Bacillus strains isolated from this Southern Italian sausage, made without a selected starter, suggest that Bacillus strains, always present in meat curing, could play a role in the development of texture and organoleptic characteristics of the sausages.