Effects of processing parameters on the caffeine extraction yield during decaffeination of black tea using pilot-scale supercritical carbon dioxide extraction technique.

摘要: In this pilot-scale study supercritical carbon dioxide (SCCO2) extraction technique was used for decaffeination of black tea. Pressure (250, 375, 500 bar), time (60, 180, 300 min), temperature (55, 62.5, 70 °C), CO2 flow rate (1, 2, 3 L/min) and modifier quantity (0, 2.5, 5 mol%) were selected as parameters. Three-level five-factor response surface methodology experimental design with a Box–Behnken type employed to generate 46 different processing conditions. 100% caffeine from tea removed under two conditions; one which consist 375 bar pressure, 62.5 °C temperature, 300 min time, 2 L/min 5 mol% concentration the other composed same pressure conditions 2.5 mol% concentration. Results showed that had great impact on yield.