Comparative studies on the fermentation performance of autochthonous Saccharomyces cerevisiae strains in Chinese light-fragrant liquor during solid-state or submerged fermentation

AimTo explore the metabolic characteristic of autochthonous Saccharomyces cerevisiae strains in Chinese light-fragrant liquor fermentation. Methods and ResultsInter-delta amplification analysis was used to differentiate the S. cerevisiae strains at strain level. Twelve biotypes (I-XII) were identified among the 72 S. cerevisiae strains preselected. A comparison was conducted between solid-state fermentation (SSF) and submerged fermentation (SmF) with S. cerevisiae strains had different genotype, with a focus on the production of ethanol and the volatile compounds. The degree of ethanol ranged from 280 to 452gl(-1) in SmF and from 148 to 256gkg(-1) in SSF, and SSF was found to be more suitable for the production of ethanol with higher yield coefficient of all the S. cerevisiae strains. The metabolite profiles of each yeast strain showed obvious distinction in the two fermentations. The highest amounts of ethyl acetate in SmF and SSF were found in genotype VII (3282gl(-1)) and genotype V (672gkg(-1)), respectively. In addition, the generation of some volatile compounds could be strictly related to the strain used. Compound -damascenone was only detected in genotypes I, II, X and XII in the two fermentation processes. Furthermore, laboratory scale fermentations were clearly divided into SSF and SmF in hierarchical cluster analysis regardless of the inoculated yeast strains, indicating that the mode of fermentation was more important than the yeast strains inoculated. ConclusionThe autochthonous S. cerevisiae strains in Chinese light-fragrant liquor vary considerably in terms of their volatiles profiles during SSF and SmF. Significance and Impact of the StudyThis work facilitates a better understanding of the fermentative mechanism in the SSF process for light-fragrant liquor production.