TH3107B - Method for separating caffene from coffee with supercritical liquid - Google Patents

Abstract

Method for extracting caffeine from raw coffee beans which has fed a supercritical fluid which without caffeine enters one end of the extraction vessel. which consists of raw coffee beans and pulling a supercritical fluid containing caffee along with it, continued at the end of the crossing. Remove the caffeinated portion of the coffee bean, periodically, while the freshly uncaffeinated coffee bean is loaded into the extraction vessel at the same time. The supercritical fluid containing caffeine is fed to the aqueous absorber by the counter current. Super Carbon Dioxide should be used. supercritical fluid This method of invention is more efficient than the periodic method. and resulting in coffee that isolates caffeine Improved type

Claims (10)

1. Method for extracting caffeine from raw coffee beans, which consists of: (a) Continuously feeding decaffeinated supercritical carbon dioxide containing the necessary non-caffeinated solids into the lower end of a vertically perpendicular extraction vessel containing raw coffee beans with a moisture content of 25-50% by weight. The supercritical carbon dioxide is continuously and countercurrently applied to the raw coffee beans in the extraction vessel to effectively extract caffeine from the coffee. The caffeine-containing supercritical carbon dioxide and non-caffeinated solids are continuously drawn out from the upper end of the extraction vessel. (b) Discarding the dedecaffeinated coffee beans from the lower end of the extraction vessel. (c) Slide the remaining coffee beans to the bottom of the extraction vessel to a volume considered to correspond to the volume of the dedecaffeinated coffee beans. (d) Place moist raw coffee beans with a moisture content of 25-50% into the tip of the extraction vessel in an amount considered to correspond to the amount of decaffeinated coffee beans removed from the extraction vessel. (e) Maintain the temperature in the extraction vessel at 80-140°C. (f) Feed caffeinated supercritical carbon dioxide and remove non-caffeinated solids through the tip of the extraction vessel to the adsorbent. (g) Continuously countercurrently contact the caffeinated supercritical carbon dioxide and non-caffeinated solids with water in the adsorbent at the same temperature and pressure as in the extraction vessel to extract all the caffeine contained in the supercritical carbon dioxide, only removing a small amount of the non-caffeinated solids. (h) Remove the caffeinated water from the adsorbent. (i) Remove the decaffeinated supercritical carbon dioxide. The non-caffeine solids are removed from the adsorbent (j). Supercritical carbon dioxide, considered caffeine-free and containing non-caffeine solids, is returned through the lower end of the extraction vessel to layers (a) and (k). Steps (b), (c), and (d) are repeated periodically while steps (a) and (e) through (j) are performed to efficiently extract caffeine from the raw coffee beans. 2. The method according to claim 1, in which step (a) the caffeine concentration in the supercritical carbon dioxide extracted from the upper end of the extraction vessel is at least 30% of the maximum caffeine concentration obtained, which is defined by the separation coefficient for such supercritical carbon dioxide. 3. The method under claim 2, where the concentration of caffeine is at least 70% of the maximum value. 4. The method under claim 1 in which the amount of coffee beans removed and placed in the extraction vessel is between approximately 5 and 33% of the volume of coffee beans contained in the extraction vessel. 5. The method stipulated in claim 4, in which coffee beans are removed and added to the extraction vessel, is carried out approximately every 10 to 120 minutes. 6. The method under Claim 1, in which the weight ratio of supercritical carbon dioxide to coffee beans is used, is between 30 and 100 kilograms of supercritical carbon dioxide per kilogram of coffee. 7. The method under claim 1, in which the coffee beans are removed and the coffee beans are placed back into the extraction vessel, is done using an empty box. 8. The procedure under claim 1, which subsequently involves the addition of an enhancer to the said caffeine-free supercritical carbon dioxide before feeding the supercritical carbon dioxide into the extraction vessel. 9. The method under claim (1) in which step (9) transfers at least 90% of caffeine and less than 5% of non-caffeinated solids from the supercritical carbon dioxide to water. 10. The procedure under claim 1, which subsequently involves the recovery of caffeine from the caffeine-containing water drawn from the adsorbent.