Study On The Technology And Chemical Compositions Of Lactobacillus Fermented Tea

It is a long history that use lactic acid bacteria to produce fermented food.Lactic acid bacteria are also widely applied in tea,such as Japan of pickled tea,suancha and?-amino butyric acid tea,etc.In this study,we chose FuYun 6 as the test materials.The lactic acid bacteria which was suitable for tea fermentation was selected.The strain ratio wasdetermined by mixture design,and the parameter of fermentation process were optimized by response surface method.The test results showed that:1.Lactobacillus acidophilus,Lactobacillus brevis,Lactobacillus plantarum,Leuconostoc mesenteriodes were chosen as the fermentation strains which has excellent characteristics in growth speed?capacity of acid production?tolerable acidity andantibacterial property from 6 strains of lactic acid bacteria2.This study use mixture design to optimize the ratio of fermentation strains with the viable count and lactic acid production the response values,and the regression models of the ratio of fermentation strains on the viable count and lactic acid production were built.Viable count(Y1)=+1.582E+008*A+3.408 E+008*B+9.488 E+008*C+1.157E+009*D+2.939 E+009*AB+2.539 E+009*AC+3.916 E+009*AD+1.671 E+009*BC+2.088E+009*BD+1.660 E+009*C DLactic acid production(Y2)=+6.64*A+6.77*B+7.05*C+7.15*D+1.42*AB+1.40*AC+1.96*AD+0.71*BC+1.00*BD+0.78*C D+2.088 E+009*BD+1.660 E+009*CDBy prediction,the optimized ratio of strains were that Leuconostoc mesenteriodes:Lactobacillus brevis:Lactobacillus acidophilus=2:1:3 through the regression models,and under the ratio of fermentation strains,the viable count was 1.73106 cfu/mL,the lactic acid production was 7.42827 mg/g.3.The parameter interval of processing technology was obtained by single factorexperiment with the viable count as indicator,and the results show that the saline quantity of 8%~12%?inoculation quantity of 1.5%~2.0%,the fermentation temperature of34?~38?,the fermentation time of 3.5 d~4.5 d is appropriate.4.The glucose quantity and inoculation quantity,the fermentation temperature and time were chosen as main influential parameters.To optimize this factors above on the basis of single factor experiment results by response surface method,and establish the models equation of the lactic acid production by Box-Behnken experimental design.Lactic acid production(Y3)=+7.99+0.19A-0.18B+0.20C+0.41D-7.500E-003AB-0.42AC+0.022AD-0.49BC+0.097BD+0.42CD-0.78A~2-0.55B~2-0.54C~2-1.04D~2By the predition of regression model,the best fermentation condition was that theglucose quantity was 8.88%,inoculation quantity of 1.83%,the fermentation temperature of 36.5?,the fermentation time of 4.005 d,and the lactic acid production was 8.12061mg/g.5.As the detection of fermented tea's biochemical co mponents showed,the aqueous extract during fermentation had a drop process in the first place,then increased whenfermentation time prolongs,and there is no significant difference compared with control group in the end;tea polyphenols was on the decline,felled to 26.89%after 5 daysfermentation;the change of amino acid is not obvious,total catechin amount decreased after fermentation,two types of esterscatechin content decreased,two types ofnon-galloylated catechins content increased,theanine content decreased significantly,all the essential amino acids showed a trend of rise,aspartic acid content increased,glutamate levels droped,?-aminobutyric acid increased from 0.051 mg/g to 0.126 mg/g,49 kinds of aroma components was detected,of which 29 kinds of aroma components were decreased,20 kinds in rise after fermentation,alcohols which was the main types of aromacomponent,accounts for 54.63%.