| Abstract:To explore the yeasts growth kinetics and glycosidase activities change,as well as to evaluate application potential of the selected Rhodotorula mucilaginosa in mixed fermentation of wine with Saccharomyces cerevisiae,‘Ecolly’ grape must was used as the material. Sequential inoculation treatments of R.mucilaginosa and S. cerevisiae with the time gap of 0 h, 24 h, 48 h, and 96 h were conducted. During alcoholic fermentation, total biomass, live yeasts and glycosidase activity including β-glucosidase, rhamnosidase, galactosidase, and xylosidase were measured by hemacytometer counting method, plate counting method and p-NPG method, respectively. With single inoculation of S.cerevisiae as the control, samples were taken every 24 h.The kinetics of biomass showed that sequential inoculation protocol could slow down the fermentation rate, and the later S.cerevisiae yeast was inoculated, the longer of the survival duration,the higher biomass of R.mucilaginosa.The four glycosidases exhibited higher activity at the earlier period of fermentation and mixed fermentation improved the accumulated activity of rhamnosidase, galactosidase and xylosidase. In conclusion, by inhibiting fermentation rate, lengthening survival time of R.mucilaginosa and improving the glycosidase activity, mixed fermentation, especially S48 inoculation protocol showed great potential to improve the wine aroma. |
