Technological Study on Preparation of Low Caffeine Instant Black Tea with Fresh Tea Leaves

Key words: 
• fresh tea leaves，low caffeine，instant black tea，extraction /
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Abstract: This article is oriented in studying the process technology of low caffeine instant black tea by or‐thogonal test with fresh tea leaves as raw material .By means of comprehensive assessment ,the most ap‐propriate proportion of added fresh tea leavesis 7∶3 ,i .e .decaffeinated fresh leaves per 70 g by adding 30 g chopped fresh leaves ,working as a source of enzyme fermentation for making out the best quality de‐caffeinated tea embryo .Four factors affecting theaflavins extraction from primary to secondary are stated as follows :pH ,temperature ,solid‐liquid ratio ,time .However ,the factors affecting thearubigins extrac‐tion from primary to secondary are solid‐liquid ratio ,pH ,temperature ,time .The optimal process parame‐ter for extraction of processing low caffeine instant black tea is at the temperature of 95℃ ,for the duration of 30 min extraction time ,with a solid‐liquid ratio 1∶15 and pH5 .5 .Through organoleptic evaluation ,it has been found that the better quality low caffeine instant black tea is made of fresh leaves and that the yield is also coming to 21 .4% .Besides ,there is not much difference in comparison of tradition process technique .T hus ,this process can be applied to the industrialized production of instant black tea .