【摘 要】
：
The extraction of caffeine from Korean green tea was performed by various extraction methods such as dipping,stirring,ultrasonic and supercritical CO2 extraction.The extracts were analyzed by reversed
【机 构】
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Chungbuk Teehnopark Chungbuk Health Industry Center,Chungbuk-do 2 10-340,Korea
【出 处】
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The 6th International Conference on Separation and Technolog
论文部分内容阅读
The extraction of caffeine from Korean green tea was performed by various extraction methods such as dipping,stirring,ultrasonic and supercritical CO2 extraction.The extracts were analyzed by reversed-phase high performance liquid chromatography (RP-HPLC).From the experimental results,the amount of caffeine extracted by supercritical CO2 extraction using water as co-solvent was 2 times larger than that by all of the different extraction methods applied.Moreover,the amount of caffeine extracted by supercritical CO2 extraction increased with increasing co-solvent content such as water and ethanol,and increased markedly by the addition of water as co-solvent.This may be due to swell of Korean green tea tissue by the addition of water and facilitation of caffeine diffusion out of that [1,2].The amount of caffeine extracted by ultrasonic at intensity of 400 W was larger than 200 W,and it was much larger than that by dipping.This is caused by the mechanical effect of ultrasonic to disrupt plants cell walls.It allows greater penetration of solvent into the green tea matrix and increases the contact surface area between solid and liquid phase.In other words,it facilitated the release of extractable compounds and enhanced mass transport of the solvent into plant cells [3,4].
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