Study On The Effect Of Pile Degree Of Dark Tea On Fuzhuan Tea "Fungus Growing" And Quality Of Finished Product

Fuzhuan tea is made of raw black tea,processed by sieving,steaming,piling(post fermentation),pressing,fungus growing and drying.and the production and processing of fuzhuan tea includes two parts: processing of dark tea and processing of fuzhuan tea.Special fuzhuan is made from second-grade and third-grade dark tea.Due to the relatively low tender degree of fresh leaves,there is often a phenomenon of uneven quality in the long-term piling process,which is prone to the phenomenon of insufficient piling or excessive piling.In actual production and processing,follow-up processing is often carried out by blending,which makes different standards of the raw materials of Fuzhuan tea,resulting in large differences in the quality of dark tea on the market,which affects the sales and reputation of dark tea.It is relatively large,and the quality of the Fuzhuan tea produced after being blended is also difficult to stabilize.Therefore,In this study,we use Zhuyeqi breed of one bud,three or four leaves as the main raw material,according to the fixing,rolling,pile-fermentation and dry process processing,five kinds of black tea with different degrees of pilling were prepared by controlling the time of pillowage for 0h,4h,16 h,21h and 26 h,probe into its quality and sensory differences,and further processed into fuzhuan tea,its corresponding markers for F-DT0、F-DT1、F-DT2,FDT3 and F-DT4 tea samples,explore pile-fermentation of degrees of fuzhuan tea finished product quality and the influence of the process of "fungus growing".The main results are as follows:(1)There are large difference between the composition and sensory quality of the degrees of different pile-fermentation,which contain quality content exist significant difference,the study found that,with the deepening of the pile-fermentation,the quality indexes content in amino acids,water extract,soluble sugar,tea polyphenol content and total catechins composition of non-ester type,and showed a trend of decrease in dark tea,flavonoids,caffeine content and the ester type catechins composition and its total volatility change,its content increased slightly.In terms of volatile components,the aroma components of dark tea are mainly alcohols and ketones,followed by hydrocarbons,aldehydes and acids.In this experiment,a total of 20 aroma compounds,including 1-pentene-3-alcohol,were measured and shared by five samples of dark tea with different degrees of piling,and they are considered to be important aroma compounds that constitute the characteristic aroma of black hair tea.Combined with the results of sensory evaluation,it is believed that the dark tea which moderate pile-fermentation is more excellent in physical and chemical indicators and senses.(2)The degree of the dark tea has an impact on the quality components and sensory qualities of the fuzhuan tea during the "fungus growing" process.During the " fungus growing" process of the five fuzhuan tea samples,amino acids,flavonoids,tea polyphenols,The content of water extracts and soluble sugars tended to decrease.Among them,the decreasing trend of tea polyphenols and soluble sugar content was more obvious,and the content of amino acids decreased only slightly,but F-DT2 tea samples and F-DT3 tea samples were in their process of "fungus growing ",the content of water extracts showed an upward trend,and the soluble sugar content of the F-DT3 tea sample also increased slightly,indicating that the quality of the moderately preformed green tea has a certain degree of quality during the " fungus growing " process of the fuzhuan tea improve.Combined with the results of sensory evaluation,it is found that the finished tea brick tea finished with a certain degree of green tea has a more mellow taste,a richer floral fragrance,and a more orange and bright soup.In summary,it is believed that the moderate green tea slabs have better quality during the processing of fuzhuan tea,and "fungus growing" has a better effect on improving its quality.(3)The degree of dark tea has a greater influence on the aroma components of Fuzhuan tea.The results show that the number of aroma components in the tea samples of F-DT2 and F-DT3 is the largest,with 47 kinds,indicating that the pile is moderate and the black is lighter.Fuzhuan brick tea made from raw materials of raw tea has the largest number of aromas.Among them,linalool with other fourteen aroma compounds are five kinds of aroma compounds commonly owned by fuzhuan tea.Combined with sensory evaluation,these aroma components are considered as the main component of the floral aroma of fuzhuan tea fungus.The aroma components in fuzhuan tea are mainly composed of alcohols.With the increase of the raw materials of fuzhuan tea,the relative content of alcohol aroma in fuzhuan tea products shows a "W" type change;the relative content of hydrocarbon aromas is "M" type change;ketone aroma,aldehyde aroma,acid aroma,ester aroma and other aromas all fluctuated;ether aroma was not detected in the finished Fuzhuan tea made from dark tea raw materials The overall trend was an upward trend and a downward trend after moderate accumulation;phenolic aromas were only detected in F-DT0 and F-DT3 tea samples,and the contents were relatively low,at 0.17% and 0.07%,respectively.