Study Of Production Technology On High Active Dry Kiwifruit Wine Yeast

One kiwifruit wine yeast stain which has been breeded was selected as experimental strain and malt wort was selected as basal medium in this study. Making use of JMP,Box-Behnken response surface quadratic and orthogonal design , fertile medium and freeze-drying protestant formula were definited,fertile cultivation and trehalose accumulative conditions were optimized. At last a kind of kiwifruit wine active dry yeast matching to standard was developmented.The result of study is aimed to provide experimental basis for industrialized production of kiwifruit wine. The result indicated:1.The result of JMP design of fertile medium and fertile cultivation conditions indicated:glucose,(NH4)2HPO4,MgSO4,vitamin B1,vitamin B2,pantothenic acid,temperature,initial pH, volume of medium,rotated speed and time have significant influence on cell proliferation,FeSO4 and biotin have no influence.2.The result of Box-Behnken response surface quadratic design of fertile medium indicated: optimum fertile medium formula of cell proliferation is glucose8.39g/L ,(NH4)2HPO40.53g/L , MgSO40.07g/L , vitamin B11.75mg/L , vitamin B20.60mg/L , pantothenic acid0.57ml/L,the prediction value of biomass reach to 3.01785×108.3.The result of Box-Behnken response surface quadratic design of fertile cultivation conditions indicated : optimum cultivated conditions of cell proliferation are temperature28.5℃,initial pH4.5,rotated speed 175r/min,volume of medium65mL and time30h,the prediction value of biomass reach to 3.06352×108.4.The growth curve of experimental strain under optimum fertile medium and optimum cultivated conditions indicated:lag phase of yeast growth is from 0h～10hexponential growth phase is from 10h～22h,after 22h it reach to stabilization period.5.The result of orthogonal design of trehalose accumulative conditions inside cell indicated:. The importation of temperature time pH and rotated speed factors is temperature>time>pH>rotated speed,optimum conditions are temperature37℃,pH5,time5h,rotated speed50r/min.6.Using normal saline as suspended,the protective effects of sugar,trehalose,skim milk powder and ascorbic acid were studied. The result of JMP design indicated:All of protestants have significant influence on freeze-drying of yeast. 7.The result of Box-Behnken response surface quadratic design of freeze-drying protestant formula indicated: optimum freeze-drying protestant formula is sugar121.1g/L,trehalose93.9g/L,skim milk powder145.4g/L and ascorbic acid10.5g/L,the prediction value of living yeast rate can reach to 92.2075%.8.The kiwifruit wine active dry yeast obtained from this study matched to trade standard of brewing active dry yeast(QB 2074-1995) in both sensory and physical-chemical characteristics.