Diversity and enzymatic profile of yeasts isolated from traditional llama meat sausages from north-western Andean region of Argentina

Abstract

Llama meat fermented sausages are traditional products consumed in the Andean region of South America. The diversity and dynamics of yeasts present in these meat products were evaluated in two productions. The results demonstrated that yeast population increased during fermentation and it remained stable throughout the ripening period. A total of 414 yeasts isolated during different stages of production were identified and characterized by molecular methods. In both productions, Debaryomyces hansenii was found as the dominant species followed by Candida zeylanoides, although other species of the genera Candida, Cryptococcus, Metschnikowia, Rhodotorula, Rhodosporium, Trichosporon and Yarrowia also contributed to the fermentation. The fingerprinting analyses by RAPD-PCR of M13 minisatellite revealed the presence of different genotypes within D. hansenii and C. zeylanoides throughout the manufacturing process. Assay of proteolytic activity revealed that Yarrowia lipolytica from production A and Candida deformans, Cryptococcus curvatus, Rhodotorulamucilaginosa and Rhodosporiumdiobovatum from production B were able to hydrolyze meat proteins. All yeast species, excluding Torulaspora delbrueckii, exhibited lipolytic activity, whereas esterase activity was detected only in few species. A correspondence between enzymatic activity and RAPD M13 profiles was observed for yeasts of production A but this correspondence was not found in production B. An appropriate selection of yeast strains as starter cultures is fundamental for quality improvement of artisanal meat products.