초록 ▼

By the extraction with CO2 at 60 to 150 bar and 20°to 70°C., an aroma enriched fraction is taken from the moistened black tea, said fraction being added again to already decaffeinated and dried tea. Decaffeination starts after the aroma fraction has been obtained by pumping carbon dioxide at a press

By the extraction with CO2 at 60 to 150 bar and 20°to 70°C., an aroma enriched fraction is taken from the moistened black tea, said fraction being added again to already decaffeinated and dried tea. Decaffeination starts after the aroma fraction has been obtained by pumping carbon dioxide at a pressure of between 150 to 500 bar and a temperature of between 10°to 100°C. through a bulk moistened tea. The solvent charged with caffeine is passed over an adsorber or purified by reduction of density.

대표청구항 ▼

In a process for the production of an aromatic decaffeinated tea comprising the steps of (a) charging the tea to be treated to a pressurizable vessel (b) dearomatizing the tea by treatment with carbon dioxide at a pressure of from about 60 to about 150 bar at a temperature of from about 20°to about

In a process for the production of an aromatic decaffeinated tea comprising the steps of (a) charging the tea to be treated to a pressurizable vessel (b) dearomatizing the tea by treatment with carbon dioxide at a pressure of from about 60 to about 150 bar at a temperature of from about 20°to about 70°C.; (c) separating the carbon dioxide from the tea, reducing the pressure of the carbon dioxide and separating therefrom an aroma containing fraction; (d) decaffeinating the tea which has been dearomatized in accordance with step (b) by treating said dearomatized tea with carbon dioxide at a pressure of from about 150 to about 500 bar at a temperature of from about 10°to about 100°C. in the presence of moisture; (e) separating said moist, caffeine containing carbon dioxide from the tea and releasing the carbon dioxide from said caffeine containing extract; (f) drying the decaffeinated tea; and (g) restoring the aroma by addding to said decaffeinated and dried tea the aroma fraction isolated in step (c); the improvement comprising raising the water content of the tea of step (b) to about 10 to 50% by weight of said tea, whereby the aroma fraction of step (c) is obtained as a caffeine free aqueous suspension/solution and wherein step (d) is carried out in the same vessel utilized to step (b); after step (c), adding sufficient water to maintain the water content of the dearomatized tea at between 10 and 50% by weight of said tea; and restoring the aroma by adding said aqueous aroma fraction to the decaffeinated and dried tea at ambient pressure.