Study On Pressing Cake And Storage Of Old Shoumei

The purpose of this paper is to study the changes of pressing cake on the aged white tea cake and the effect of different temperature conditions on the storage of the aged white tea cake.In this paper,the experimental materials of aged white tea are aged Shoumei loose tea and aged Shoumei cake tea.The aged Shoumei cake tea is divided into aged Shoumei cake tea(xianya)means taht the new tea procesed cake tea,and aged Shoumei cake tea(houya)is Shou loose tea stoed before pressing cake tea.The materials were three different years of aged Shoumei loose tea,aged Shoumei cake tea(xianya)and aged Shoumei cake tea(houya).The differences between aged Shoumei loose tea and aged Shoumei cake tea,and between aged Shoumei cake(xianya)and aged Shoumei cake tea(houya)were compared and analyzed.Aged Shoumei cake tea was used as the test material.Three different conditions were set up:indoor natural conditions,25 ℃(humidity 10-20%)and 45 ℃(humidity 10-20%)storage of aged Shoumei cake tea for 10 months.The effect of temperature on the storage of aged Shoumei cake was investigated.The main results are as follows:1.The biochemical components of aged Shoumei loose tea changed after pressing cakes.The contents of caffeine,catechin,flavonoids,theaflavins and thearubin in aged Shoumei cake tea(xianya)and agedShoumei cake tea(houya)increased,while the contents of tea polysaccharide,soluble sugar and thearubin decreased.After cake pressing,the total amount of free amino acids in aged Shoumei cake tea showed a decreasing trend,but aspartic acid showed an increasing trend.After cake pressing,the total organic acids of aged Shoumei cake tea decreased,but caffeic acid in organic acids showed an increasing trend.2.The aroma characteristics of aged Shoumei cake tea become more prominent after pressing cakes,which is different from Shoumei loose tea.The results of PLS-DA analysis showed taht the aroma difference between aged Shoumei cake tea(xianya)and aged Shoumei cake tea(houya)was small.Compared with the aged Shoumei loose tea,the major changes in aroma components of the aged Shoumei cake tea(xianya)and the aged Shoumei cake tea(houya)were the decrease of linalool compounds and methyl salicylate.Pressing cake may accelerate the aging of aged Shoumei tea,and is more conducive to the promotion of the quality of aged Shoumei tea.3.The aging degree of aged Shoumei cake stored at 45℃ was higher in different indoor natural conditions,25℃ conditions and 45℃conditions.The overall difference between indoor natural conditions and25 C conditions was small.4.The flavor and aroma components of the aged Shoumei cake tea vary greatly during storage.Tea polyphenols,catechins,soluble sugarsand the total content of organic acids showed a downward trend,while the content of caffeine increased slightly,and the content of flavonoids increased substantially.In aroma components,cis-3-hexenol,linalool,1-pentene-3-alcohol and methyl salicylate showed a decreasing trend,while hexanal showed an increasing trend.5.During the storage of aged Shoumei cake tea,the dynamic changes of methyl salicylate and salicylic acid are prominent in the flavor and aroma components.During the storage of aged Shoumei cake tea,methyl salicylate showed a decreasing trend,while salicylic acid showed an increasing trend.The dynamic change between the methyl salicylate and salicylic acid may be an important feature of aging of aged Shoumei cake tea.6.The result of economic benefit analysis shows that the storage of aged Shoumei cake tea not only contributes to the improvement of the tea quality,but also increased economic benefit.The research on the storage of aged Shoumei cake tea has certain guiding significance for the actual production of enterprises.