Study On Manufacturing Process Of Pu-erh Tea Drink

Pu-erh tea is a kind of after-fermentation tea which is of many kinds of health care functions, such as reducing blood lipids, weight loss, anti-microbes and anti-cancer. Up to now, the researches on Pu-erh tea mainly focused on the pharmacology function through animal test, however, there was few report on its application, especially Pu-erh tea drink development. In order to establish the manufacture technique of Pu-erh tea drink which has the merits of transparent, long preservation, low cost and meeting the safe standard of health food, this paper studied on the technology of material extraction, clarification with membrane, drink confection and sterilization according to the characteristic of Pu-erh tea. The results showed:1. Use distilled water as solvent of material extraction, through comparing with extracting efficiency and operating costs, the optimal extraction condition of Pu-erh tea was ratio of tea to water was 1:30, extracting temperature and time was 85℃ and 15 minutes respectively, one time extraction was chose.2. In order to determine the optimal operating parameters of clarification, the clarification effect of different physical filtration methods including ordinary filter paper filtering, centrifuge filtering, vacuum filtering, filtering after low temperature treating and micro-filtering were compared, especially the permeation ability of Pu-erh tea liquid and contents of main taste components of tea liquid filtered with different aperture membranes under different operation condition was studied. The results showed that membrane filter clarification solved the problem of muddy and sediment more effectively, and high-molecule substances were obstructed with 0.2μm micro-filter membrane and clarification of Pu-erh tea liquid was increased markedly, and the retaining rate of main components was high in the case of optimal micro-filtration process accompanied with good organoleptic quality.3. This paper mainly studied on confection of pure Pu-erh tea drink and developed compound tea drink. The results showed that tasteless pure tea should be micro-filtration liquid diluted five times. That is, solid substantial content 750-792mg/L, polyphenol content 340-363mg/L, and caffeine content 160-189mg/L; strong pure teashould be micro-filtration liquid diluted four times. That is, solid substance content 960-980mg/L, polyphenol content 410-432mg/L, caffeine content 200-210mg/L. Compound tea drink should added 5 X 10-5 % special essence of Kang Shi-fu black tea and 5 X 10-4% stevia into the tea liquid.4. On the base of former study, following six sterilization methods were tried, 108 ℃(M0), 110℃(Mi), 112℃(M2), 115℃(M3), 121℃(M4) and 121℃(M5). The effect of different sterilization methods on physical properties of Pu-erh tea drink was studied and the microbe was cultured. Results showed that the effect of temperature and time on the brightness and sedimentation of Pu-erh tea was significant. Higher temperature and longer time was, darker color and lower permeation rate was got; what's more, macroscopic sedimentation could be seen after 24 hour storage. The optimal sterilization method should be 112 ℃ sterilization (Ma) (rise temperature 7min, constant temperature 12min, reduce temperature 7min); 115℃sterilization (Ms) (rise temperature 8min, constant temperature 10min, reduce temperature 8min).