Study on Microwave-assisted Extraction Process for the Caffeine from the Green Tea

The solubilization characteristics of caffeine in green tea was studied.The effect of the ratio of solid to liquid,the extraction temperature,the extraction time,the pH value of the extraction liquid,the microwave powder,the microwave treatment time on the solubilization characteristics of caffeine in green tea were tested.Microwave-assisted extraction process for the caffeine from the green tea was studied by the orthogonal experiment.The result of quantitative analysis of the extracting rate of caffeine indicated that the extracting rate of caffeine in green tea was more than 3.90% under the condition was: the ratio of solid to liquid was 1:30,the extraction temperature was 90℃,the extraction time was 30min,the pH value of the extraction liquid was 6,the microwave powder was 350W,the microwave treatment time was 20s.