Study Of Selection Of Excellent Special Yeast For Lemon Wine Made Of Lemon Juice And Sugar Cane Juice & The Fermentation Process

Lemon from An'yue county in Sichuan province and sugarcane from Yuunanprovince are the experimental materials for fermented lemon wine. Three major researchsare done in this study:The adaptability of different yeast to the fermentation of lemon wineare tested, and an excellent special yeast germ is suitable for the fermentation of lemonwine;The best conditions of primary fermentation,clarification and removing of bittercomponents of lemon wine are studied;The aroma component of wine lemon isdetected,and the flavour enhancing technology is studied initially.The main contents andresult on this study are as follows:1. The selection of excellent yeast germ: 3 in 7 kinds of different yeasts are proofbetter according to their fermentation performance in fermenting test,and then theirefficency of producting alcohol and antireversion force are tested. Result indicat:In 7 kindsof yeasts, 1^#,6^#,7^# have better fermentation performance than others.The yeast 6^# fermentmost quickly, and has a higher alcohol-producting alcohol rate. It's performance ofanti-high osmotic concentration,anti-sulfur, acid-proof and alcohol-proof are excellent. Theoriginal lemon wine fermented by the yeast 6^# tastes best,and has best senses evaluation.Itis proof that the yeast 6^# were most suited for lemon wine's fermentation.2. The assurance of the fermenting conditions of lemon wine: The temperatureinoculum concentration,sugar-concentration and acidity of the mixed juice of lemon andsugarcane are studied with orthogonal design-L₉(3⁴),and the results show: to the quality oflemon wine,the sugar-concentration is the most influential factor.The acidity of mixed juiceis secondary.The fermenting temperature is third, and the inoculum concentration is the lestinfluential factor.The best fermenting condition is that: the sugar-concentration of mixedjuice 22%,pH3.8,fermenting temperature 17℃and inoculum concentration 6%(inoculumconcentration is equivalent to 0.8～1×10⁸ yeast cell per milliliter).3. The clarification of lemon wine:Firstly, the lemon wine is dealed with 6 kinds ofclarifiers. Then,the clarifiers with better clarifying effects are used to clarify compositelylemon wine. The results show:In 6 kinds of clarifiers, Bentonite is the best clarifier, and thehighest transmission-rate of Lemon Wine was 96.7% when the dosage of bentonite is 0.15%.Chitlsan and glutin have better clarifying effects.Diatomite,pectinase and PVPP have worseclarifying effects;The result of Compound clarification show: the best clarifying effect isachieved when bentonite and chitosan are used together to clarify lemon wine.The bestdosage of bentonite is 0.125%,and chitosan's is 260mg/L; The best clarifying effect oflemon wine dealed solely with bentonite is better than that of lemon wine dealed with bentonite and chitosan together. Lemon wine clarified is gold andflavous,clear andtransparent,and its aroma is pleasing and good.The flavor is distinctive and purity.4. The removing of bitter components of lemon wine:The pretreatment of lemon withenthylene of of different dosage,Removing of bitter components of lemon with magnesiumsilicate andβ—cyclodectrin,the conditions and effect of Naringinase and Hesperidinase toremove the bitter components of lemon wine are studied in this study.The resultsshow:Ethephon(ethrel) acts insidiously to remove the bitter components of lemon wine,andthe eliminating rate is relatively low. Magnesium silicate andβ—cyclodectrin have adverseeffect to the quality of lemon wine seriously, and they are not suitable for the removing ofbitter components of lemon wine.The effect of Naringinase and Hesperidinase to removetogether the bitter components of lemon wine is better than that of Naringinse orHesperidinase to treat the lemon wine independently.The best condition for Naringinse orHesperidinase to treat the lemon wine together is that:dosage of Naringinase is 1.75 g/L;thedosage of Hesperidinase is 0.5 g/L;the treating temperature is 50℃,and the processingtime is 90 mins.5. Flavour enhancing of lemon wine and detection of aroma components:The aromacomponents of lemom juice,sugar juice,lemon wine and lemon wine dealed withβ-glucosidase with two kinds of methods are detected in this study.The results show:(1) The major aroma ingredients of lemon wine are as follows:Alcohols are 3-methyl-butylacohol,2-methyl-butylacohol and phenethyl alcohol,andthe content is individualy 56.31%,8.82% and 4.43%.Acids are lactic acid, pelargonicacid,Butanoic acid, and the total content of acid is 9.07%.Ester are ethyl isovalrate andisoamyl acetate, and the total content of ester is 8.32%.The aroma components from lemoninclude mainly terpineol and its derivatives: Terpineol,Nerol, 1-p-Menthen-9-al, 1-Terpinen-4-ol 1,8-Terpin and so on, and the total content is 6.08%. The aroma conponents fromsugarcane are acetosyringone,lactic acid,palmitic acid and alkane and so on.(2)The major aroma components of lemon wine treated byβ-glucosidase are stillalcohols,esters and acids.Compared to the lemon wine which have not been treated byβ-glucosidase,the aroma ingredients of lemon wine treated byβ-glucosidase from lemonincrease in kinds and relative content. The relative content of aroma ingredients fromlemon in lemon wine treated directly byβ-glucosidase is higher than that in lemon winefermented by the mixed juice treated byβ-glucosidase made of lemom and sugarcane.