A survey of yeasts in traditional sausages of Southern Italy

The evolution of the yeast population during manufacturing and ripening of `salsiccia sotto sugna', a typical salami of the Lucania region (southern Italy), was investigated. Four different batches, produced in four farms in Lucania, were studied. Each batch showed a specific yeast population, and the most frequently isolated yeasts belonged to Debaryomyces hansenii and its anamorph Candida famata, and Rhodotorula mucilaginosa. Yarrowia lipolytica was isolated from three sausage batches. The Y. lipolytica isolates were further characterised, in particular for their lipolytic activity on pork fat. Lipolytic activity was maximal at pH 5.5, with oleic and palmitic acids as major free fatty acids produced. The use of randomly amplified polymorphic DNA-polymerase chain reaction allowed the detection of a high genetic heterogeneity among the isolates phenotypically assigned to the species Y. lipolytica.