Study On The Selection Of Superior Saccharomyces Cerevisiae And The Effect Of Deacidification For Kiwi Wine

The study aimed at two problems to be solved, one is that Kiwi wine in industrial production lacks of the specialized and excellent Saccharomyces cerevisiae to ferment; the other is that the raw Kiwi wine has high acidity. Using wild kiwi fruits of Tian Quan as raw material, We carried the study on the selection of superior Saccharomyces cerevisiae and the effect of Deacidification for Kiwi fruit. The results of this experiment has a certain theoretical and practical significance to improve the quality and taste of Kiwi fruit. The main results of this paper are as follows:(1) Respectively from the fermentation force, liquor yield, fermentation rate, SO2 tolerance, acid resistance, alcohol resistance, sugar resistance to compare the properties of Lalvin EC 1118 Saccharomyces cerevisiae, Clos Saccharomyces cerevisiae and White Saccharomyces cerevisiae which three strains of Saccharomyces are often used in wine fermentation. The results showed that three strains of wine yeasts all can meet the requirements of the maximum amount of SO2 added in wine fermentation, in addition, Lalvin EC1118 Saccharomyces cerevisiae possess largest fermentation force, highest acid resistance, highest alcohol resistance, highest sugar resistance, the moderate fermentation rate and liquor yield, while Clos Evolution Saccharomyces cerevisiae has worst fermentation force, ferment too fast, lowest liquor yield and the weak tolerance of varieties; as the control group, White Saccharomyces cerevisiae s characteristics centered. After comparing and considering, EC1118 Saccharomyces cerevisiae has the excellent characteristics.(2) With the three strains of Saccharomyces cerevisiae to ferment the same Kiwi puree, comparing the effect of quality and flavor of the Kiwi wine fermented by different yeasts through measuring physical and chemical indicators, the sensory evaluation and volatile substances. The results showed that:the Kiwi wine fermented by EC1118 Saccharomyces cerevisiae has minimum residual sugar, highest alcohol, minimal Vc loss, the moderate color and acidity, the highest clarity; the main flavor substances of Kiwi wine are alcohols, esters, as well as a small amount of alkenes, aldehydes, ketones, etc; the Kiwi wine fermented by EC1118 Saccharomyces cerevisiae has the most alcohols and esters, while the Kiwi wine fermented by White Saccharomyces cerevisiae has the least alcohols and esters; sensory evaluation results are Kiwi wine fermented by EC1118 Saccharomyces cerevisiae has the smallest acidity and astringency as well as most concentrated aroma. After comparing and considering, different yeasts fermented the same kiwi puree can produce different quality and flavor of Kiwi wine and the Kiwi wine fermented by EC1118 Saccharomyces cerevisiae has the best quality and flavor.(3) In the study of deacidification of Kiwi wine, the separate deacidification experiments show that at room temperature, Na2CO3 and Chitosan have good effect on deacidification of or Kiwi wine, especially 1.8g/L and 2.0g/L of Na2CO3,5.0g/L and 6.0g/L of Chitosan, while Potassium has little effect; Seen from compound deacidification experiment,2.2g/L of Na2CO3 and 6.0g/L of Chitosan has the best effect of deacidification. Its result was that the total acid of Kiwi wine dropped to 7.63g/L, deacidification rate was 43.9%, the light transmission rate of Kiwi wine was 99.7%.