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出 处:《黑龙江八一农垦大学学报》2013年第2期85-87,共3页journal of heilongjiang bayi agricultural university
摘 要:乙醇作溶剂从茶叶中提取咖啡因,以咖啡因产率为评价指标,采用先超声、后采用浸提提取工艺,考察乙醇体积分数、料(茶叶)液(乙醇)比、超声频率、超声时间、后浸提温度和后浸提时间影响。结果表明:在乙醇体积分数95%,料液比1∶12,超声频率25.00 kHz,超声时间10 min,后浸提温度70℃,后浸提时间100 min时,得到产率为34.81%、熔点为236℃的白色针状晶体。With caffeine yield as index and ethanol as solvent extraction of caffeine from tea, first using ultrasound, then extracting technology, effect of ethanol volume fraction, the ratio of solid (tea) to solution (ethanol), ultrasonic frequency, ultrasonic time, post-extraction temperature and post-extractiontime were studied. The white needle crystal caffeine with 34.81% yield, melting point of 236 ℃ was obtained under the conditions of ethanol volume fraction 95%, solid-liquid ratio 1:12 ,ultrasonic frequency 25.00 kHz, ultrasonic time 10 min, post - extraction temperature 70 ℃ and post-extraction time 100 min.
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