Study On Application Of Yeast Strain (X16) In White-wine Brewage

Origin,wine grape varieties,yeast characteristics affect the wine type,quality and typical.They are the key factors of the wine production.Alcoholic fermentation is an important process of wine brewing.Moreover,property of yeast strain is closely associated with the quality of the wine.This work mainly focused on the factors including fermentation temperature,yeast inoculation sizes,grape juice sugar,and grape varieties how to impact white wine alcohol fermentation process of yeast strain(X16),so that we could screen fermentation process to produce high quality white wine with regional characteristics in Tianjin.The results were as following:Firstly,the results showed that the start times of fermentation were all 1 to 2 days under fermentation temperature at 16℃,18℃and 20℃,indicating that different fermentation temperatures did not impact the start times of yeast strain(X16).However,the decrease in sugar degree was significant.Fermentation rate increased about 20% with temperature increasing of 2℃.Meanwhile,the whole fermentation time was shortened about 2-3 days at high temperature.Additionally,we also found that the fermentation rates increased 50% under inoculation sizes 0.2 g/L,0.25 g/L compared with 0.15 g/L,although the different inoculation sizes did not significantly start time of fermentation.Particularly,0.15 g/L inoculation size resulted in increase(about 4-5 day)of the total fermentation time.The fermentation was not fully completed under 0.15 g/L inoculation size.With the grape juice of sugar degree increases,fermentation time extend under the condition of different temperatures.Fermentation rate of three varieties grapes: Muscat Hamburg > Riesling > Chardonnay,high acidity inhibit fermentation.Secondly,different fermentation temperatures did not significantly impact the dry white wine reducing sugar,total acid,and free SO2.Dry white wine sour content at 20℃ fermentation was higher than that at 16℃ and 18℃,which was up to 0.4 g / L.At the same time,we also found that the brewing wine aroma rich delicate elegance,taste the pure cool,net lively,typical of the strongest,and sensory evaluation were the highest at 18℃ fermentation.Alcoholic level with inoculation size(0.15 g/L)was only 0.5%vol.Moreover,the content of wine reduction sugar residue was much more 4g / L,indicating that fermentation is not complete.The volatile acid levels reached to 0.4-0.5 g/L under inoculation size(0.15 g/L).Interestingly,there were no significant different in wine indexes between 0.25 g /L and 0.2 g/L of the inoculation sizes.However,the wine in aroma was full-bodied,alcohol positive,and fresh taste of relatively cool net,coordination,typical strong,comprehensive sensory evaluation of highest under the inoculation size 0.2 g/L.Grape juice sugar high wine taste more mellow;Italian Riesling and Chardonnay varieties in high glucose fermentation degree of the wine aroma is more full-bodied,and Muscat Hamburg to the contrary.Taken together,these results showed that the suitable fermentation temperature for yeast(X16)was ideal yeast for liquor and aged white wine brewing with 18℃,suitable additive quantity was 0.2 g/L,with strong high sugar,high alcohol tolerance,more suitable for brewing with ageing potential Chardonnay dry white wine.