Systematic analysis of the aroma profiles produced by Zygosaccharomyces rouxii Y-8 in different environmental conditions and its contribution to doubanjiang (broad bean paste) fermentation with different salinity

This study aimed to provide a systematic analysis of the effect of environmental factors on the growth and volatile flavor compounds (VFCs) production ability of Zygosaccharomyces rouxii Y-8 and further elucidate its contribution to doubanjiang fermentation in different salinity. Lower salinity (0–9%), acidic pH (4.5–5.5), moderate temperature (25–35 °C) and air exposure favored the growth and VFCs accumulation of Z. rouxii Y-8, which also had higher concentrations of key jiang flavor contributing compounds benzene ethanol, 2-methoxy-phenol and pyrazines. Interestingly, samples with higher VFCs concentration were found to contain less kinds of VFCs. When inoculated into doubanjiang fermentation, Z. rouxii Y-8 showed critical roles on the formation of VFCs in doubanjiang. Among doubanjiang samples fermented in different salinity, doubanjiang with 9% salinity had the highest kinds of VFCs. Moreover, its flavor was more balanced and the jiang flavor was stronger. This indicated that the presence of adequate salinity was necessary for Z. rouxii Y-8 to produce critical VCFs responsible for doubanjiang flavor. The results would provide researchers and manufacturers with a deeper understanding of the characteristics of Z. rouxii Y-8 and rationales to utilize Z. rouxii Y-8 as starter to produce high quality BBFFs.