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Background and Aims: Terpenes are major varietal aroma compounds significantly contributing to wine quality and style. Autochthonous microbial starters can promote the formation and release of the terpenes and thus highlight the terroir typicality of wines. This study compared the physicochemical parameters, changes in the terpene concentration, β‐D‐glucosidase activity and sensory attributes of Chardonnay wines fermented individually by the Saccharomyces cerevisiae autochthonous MQ3 strain isolated from spontaneous fermented grape must and by three commercial S. cerevisiae strains. Methods and Results: The evolution of terpenes during alcoholic fermentation was followed with ultrasound‐assisted liquid–liquid extraction combined with GC. The physicochemical parameters of wine fermented by the MQ3 strain were significantly different from those of the wines fermented by other yeasts. The pattern of the terpenes detected, including linalool, α‐terpineol, farnesol, geraniol, nerol and citronellol, varied during alcoholic fermentation. The MQ3 strain induced greater accumulation of terpenes with increased concentration of α‐terpineol, geraniol and (E,E)‐farnesol. Besides, the MQ3 strain exhibited an enhanced ability to produce β‐D‐glucosidase compared to that of the other three strains. With the exception of α‐terpineol and (E,E)‐farnesol, there was no significant correlation between the concentration of the other terpenoids and β‐D‐glucosidase activity as shown by Pearson's correlation analysis. Wine produced with the MQ3 strain was characterised by a distinctive complex flavour with enhanced floral and fruity aromas. Conclusions: The autochthonous MQ3 strain had a positive effect on the varietal aroma and sensory quality of the wines. Significance of the Study: Due to its aroma enhancing ability, the MQ3 strain could be applied to produce quality Chardonnay wine with terroir typicality. [ABSTRACT FROM AUTHOR]

Abstract: This study reports an ethanol yield of 270L/ton wood from lodgepole pine pretreated with sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) using an adapted strain, Saccharomyces cerevisiae Y5, without detoxification. The enzymatic hydrolysate produced from pretreated cellulosic solids substrate was combined with pretreatment hydrolysate before fermentation. Detoxification of the pretreatment hydrolysate using overliming or XAD-4 resin before being combined with enzymatic hydrolysate improved ethanol productivity in the first 4h of fermentation and overall fermentation efficiency. However, detoxification did not improve final ethanol yield because of sugar losses. The Y5 strain showed excellent ethanol productivities of 2.0 and 0.8g/L/h averaged over a period of 4 and 24h, respectively, in the undetoxified run. The furan metabolization rates of the Y5 strain were significantly higher for the undetoxified run than those for the detoxidfied runs, suggesting it can tolerate even higher furan concentrations than those studied. Preliminary mass and energy balances were conducted. SPORL produced an excellent monomeric sugar recovery value of about 85% theoretical and a net energy output of 4.05GJ/ton wood with an ethanol energy production efficiency of 178% before distillation. [ABSTRACT FROM AUTHOR]