Presence, changes and technological properties of yeast species during processing of pastirma, a Turkish dry-cured meat product

In this study, alterations in yeast dynamics during pastirma processing, and technological (growth at different pH, temperature and NaCl conditions, lytic and enzymes activity) properties of yeast strains were investigated. The pH values of pastirma samples increased throughout pastirma processing, while moisture and water activity (aw) decreased. Initial yeast population decreased from 4.42 log cfu/g to 3.61 log cfu/g during the curing process. Considering the genotypic identification, a total of 100 isolates were obtained from pastirma samples. The dominant yeast species was Candida zeylanoides (58%) which was followed by Candida deformans (12%) and Candida galli (11%), respectively. These yeast species were found at all sampling points. Trichosporon japonicum (2%), Cryptococcus curvatus (1%) and Debaryomyces hansenii (1%) were the least frequent species isolated from the pastirma samples. C. zeylanoides and T. japonicum did not show any proteolytic activity, and their lipolytic activity was weak. Twenty-one of the yeast isolates had nitrate reductase activity.