Research On The Process Optimization Of Purple Sweet Potato Wine

Purple sweet potato (Ipomoea batatas),is a Convolvulaceae annual herb,containing a large number of anthocyanins.The Present thesis was focused on the fermentation conditions,changes of compositions in the fermentation and security of purple sweet potato wine,which was used purple sweet potato as raw material. The conclusions are as follows:1.Processing technology of purple sweet potato wine was identified.Choose fresh,non-moldy purple sweet potato via cooking and beating into sweet potato plasm with water twice volume or use the purple sweet potato cooked powder with water five times,then liquefy and saccharify the plasm with liquid a-amylaseo,glucoamylase respectively,and inoculate and yeast finally.Through single factor and orthogonal trials,the primary and secondary factors were yeast species>fermentation temperature>yeast inoculum volume>pH of purple sweet potato plasm.Optimal conditions for fermentation were the Dutch yeast,fermentation temperature26℃,yeast inoculum2.5%,pH4.5.Selection of fine yeast strains.Study the morphology of five known yeast strains.Through WL med ium,meanwhile,further identify the best yeast strain by five tolerance experiments (-high sugar tolerance ethanol tolerance of high permeability Resi-stance alkali tolerance and SO2tolerance),in the five tolerance experiments,Saccharo-myces Cerevisiae HL1-3have strong resistance,and in the non-hypertonic environment,Saccharomyces Cerevisiae YYl-3i s a fine yeast strain for purple sweet potato wine fermentation;morphology on WL medium:Saccharomyces Cerevisiae HL1-3community is blue bump,rough,the edge is fluffy,cells are spindle and Small,liquid culture is clarifyi-ng,precipitated,with membrane; Saccharomyces Cerevisiae YY1-3community is white bu-mp and smooth.2.Component changes during the fermentation of purple sweet potato wine.Physicochemical indexs were as follows:reducing sugar was going down quickly at6d below4g/L;while alcohol degree increased,and later the rate of increase was slow and tended to balance;the pH value went down was smallest at the forth day,then going up;The total acid kept increasing and was stable at last.