Technological properties and flavour formation potential of yeast strains isolated from traditional dry fermented sausages in Northeast China

The technological properties and flavour formation potential of yeast strains isolated from traditional dry fermented sausages were evaluated. A total of 46 yeast strains were isolated and characterized at the strain level by genotyping. Among them, 34 strains were selected for evaluation of technological properties (tolerance to acid, salt, and sodium nitrite stresses; proteolytic and lipolytic activities; and biogenic amine formation capacity) based on their genetic profiles. Then, seven strains (Debaryomyces hansenii HRB2, SH4, and HG2; Torulaspora delbrueckii DQ3 and HG7; Pichia kudriavzevii MDJ1; and Candida zeylanoides DQ7) were selected to investigate their flavour formation potential in a fermented sausage model. A total of 56 volatile compounds were detected in all models, of which 17 volatile compounds were the most important flavour contributors with an odour activity value (OAV) > 1. The most remarkable result was the significant production of acid, alcohol, and esters in the inoculated models, such as acetic acid, hexanoic acid, ethanol, phenethyl alcohol, ethyl acetate, and ethyl hexanoate. Of all the strains, D. hansenii SH4 was considered to be the best flavour producer because it produced multiple compounds with the highest OAVs, which are associated with the development of desirable sensory characteristics in dry sausages.