| Jasmine scented tea is one of special kinds of tea in our country. To study on the theory of adsorption by tea will provide the theoretical references on improving the processing techniques and the quality of jasmine scented tea.In the paper,the capacity of aroma adsorption by water and tea soup was clearly expounded for the first time. Infused tea was also studied in order to explain the effect of the water-extract in tea on aroma adsorption. Meanwhile,the correlation between aroma adsorption and water adsorption by tea was discussed. Four principal factors,that's the water content of tea dhool,the rate ofjasminum sambac to tea dhool,the temperature in tea stack and scenting time,were studied respectively and synthetically. And the software of Data Processing system (DPS) was used in statistical analysis. The results showed:Free water had great capacity of aroma absorption. Most of the dominant compounds in jasminum sambac could be absorbed by free water. They were linalool,p -phenylethyl acetate,phenyl methyl acetate,cis-3-hexen-l-ol acetate,Methyl salicylate,Benzaldehyde etc.. Tea soup had greater capacity of aroma absorption. Besides of the compounds absorbed by water,alcohol methyl benoate,Benzyl alcohol,cis-jasmone and nerolidol could also be absorbed by tea soup. According to organoleptic evaluation,both scented water and scented tea soup smelt like jasminum sambac. But the aroma of scented tea soup was stronger and more natural.The effect of water extract on the total amount of aroma absorption by tea was not notable,but that on the kinds and the compounding ratio of the aroma compounds were remarkable. Water extract made contributions to wards theadsorption of the aroma compounds such as linalool,phenyl methyl acetate,a -farnesene,methyl anthranilate and cis-3-hexenyl benzoate. The amount of the adsorption by normal tea dhool for three dominant aroma compounds in jasmine scented tea,that's linalool,phenyl methyl acetate,a -farnesene,was 22.42% more than that by infused tea dhool. The results of organoleptic evaluation showed that the quality of jasmine scented tea made of normal tea dhool was better by far than that made of infused tea dhool.The mechanisms of aroma adsorption and moisture adsorption were different. The results showed that the rate of the moisture adsorption by tea was higher with lower water content of tea,but for aroma adsorption,it was not the case. The rate of aroma adsorption reached the maximum while the water content of tea was 20-25%. Even if the water content of tea dhool was as high as 35.6%,the amount of aroma adsorption by tea was still high but the rate of the adsorption of moisture by tea was actually negative.The effects of the water content of tea dhool and the temperature in tea stack on the vitality ofjasminum sambac and the amount of released aroma from it were notable. In case tea dhool was too dry,they would adsorb a large quantity of water from flowers,which caused untimely wilting of flowers,and then the hydrolase activity was inhibited and jasminum sambac couldn't released free aroma adequately. Prohibitive temperature in tea stack was quite disadvantageous to the vitality ofjasminum sambac. At lower temperature jasminum sambac could still bloom,but the aroma they released was relative light,which was also disadvantageous to the adsorption for jasmine scented tea.Four principal factors in scenting process for jasmine scented tea were correlated notably. The optimal level of a factor would be changed while the level of another correlative factor was altered. Factor levels hi integration test were optimized by DPS. Provided that the maximum amount of aroma adsorption by tea dhool was aimed at,the optimal combination of factor levels was that:the water content of tea dhool was 17.9%-20.0%,the rate of jasminum sambac to tea dhool was 73.7%-77.6%,the temperature hi tea stack was 27.2-29.7 and scenting tune was 12.7h-14.0h. Provided that best organoleptic quality of jasminescented tea was aimed at,the optimal combination of factor lev...
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