摘要 |
<p>A simple, operationally reliable and economic process is described for decaffeinating green coffee, which ensures a high degree of decaffeination, avoids denaturation of further constituents of the green coffee and permits isolation of the caffeine. In this process, green coffee beans, optionally moistened to 20% by weight to 40% by weight, are first extracted with a carbon dioxide-saturated liquid solvent, preferably water, at a temperature of 20 DEG C to 110 DEG C and at a pressure of 30 bar to 300 bar and, after reducing the pressure to 1 bar to 10 bar, are rinsed with the liquid solvent. The liquid phase loaded with the green coffee constituents including caffeine is decaffeinated in a device provided downstream by treatment with supercritical carbon dioxide and is again saturated with CO2. The caffeine is washed out of the supercritical CO2 phase with water and is isolated in pure crystalline form. <IMAGE></p> |