Study On Fermentation Technology Of Inoculate Eurotium Cristatum Into White Tea Artificially And It's Quality Evaluation

White tea is very popular among overseas consumers because of its health benefits.Most people in China prefer to drink tea with strong aroma and rich taste,which limits the expension of white tea in domestic market.Eurotium cristatum is a kind of microorganism found in Fuzhuan tea,and it decreases bitterness and astringent flavor of old tea.The focus of this study is to inoculate E.cristatum into white tea artificially to improve tea quality and create a brandnew white tea product.The sensory,volatile compounds and un-volatile compounds were then analyzed.In the meantime,microorganism diversity and motabolomics were analyzed too to predict potential food safety problem.The results were as follows:1 Fermentation technology of inoculate E.cristatum into white tea artificially are studiedThe best condition to ferment white tea is 27?,90%environmental humidity and inoculate E.cristatum 1.8×103cfu.Ifter 7days,E.cristatum fermented white tea is ready.After that way,white tea turns to a small,four-side appearance and E.cristatum blossomy inside.The E.cristatum fermented white tea tastes mellow and has a Chinese date flavor.The Brewed leaves are tippy,tender,soft and reddish-brown.The amount of inoculant is the most influential factor in flowering.In terms of biochemical ingrediants,temperature is the most significant factor,followed by humidity and inoculum concentration.2 Volatile compounds are changed during white tea fermentation by means of inoculation of E.cristatumThe amount and variety of white tea volatile compounds decreases during fermentation by means of inoculation of E.cristatum.The refreshing aroma compounds such as licareol,phenylethyl alcohol and geraniol drops significantly while the mellowed aroma compounds including cedrene and cedrol increased.Inoculate E.cristatum into white tea speeds up the process of changing new white tea flavor into old white tea flavor.Alcohols take up the largest proportion of volatile compounds in new white tea and the white tea after sterilization.Without inoculate E.cristatum,Esters are the greatest volatile compounds in the fermented white tea Hydrocarbons are the most significant volatile compounds in E.cristatum fermented white tea.The Mellowed and Chinese date flavor is probably due to the existence of cedrene,cedrol and naphthalene.3 Bitter and astringent components decreased during white tea fermentation by means of inoculation of E.cristatumChanges of taste compounds are analyzed by HPLC and SP.It is found that bitter taste compounds epigallocatechin gallate(EGCG)and epicatechin gallate(ECG)plummet in number,while epigallocatechin(EGC),Asp,His,caffeine and kaempferol rise considerably.EGCG may transform into gallocatechin gallate(GCG)during the sterilization process and coexist with the same amount.Bitter taste compounds could drop during E.cristatum fermentation process,bringing about a new flavor and enriching the variety of white tea.4 Microorganism diversity and motabolomics analysis of E.cristatum fermented white teaMicroorganism diversity of E.cristatum fermented white tea are analyzed and found that E.cristatum is dominant(99%)in fungus.There is no superior bacteria.But the diversity of bacteria is more than that of fungus.Motabolomics analysis found that most key ions after E.cristatum fermentation decreased,including amino acids and carbodydrates.The amount of metabolite of amino acids and some of vitamins go up.There might be slight increase in some flavonoids and metabolite of microorganism.