Helical gear boxes H3 flender electric motor H3-CH9-B

Flender/Flender Gear Units/Helical gear boxes H3

d coffee containscaffeine ranging from 1% to 2%, depending on the variety. The caffeine content in cupof coffee ranges from 5 to 1 mg. The removal of caffeine from coffee minimizes thehealth hazards (adverse physiological effects), at the same time retaining the desirableattributes of coffee beverage. With the increased emphasis on health and the known ill effects of caffeine, more people are switching over to beverages with less or no caffeine. The share of decaffeinated coffee in the .. (coffee) market has risen above 2% andis still on the increase. Kaffee HAG in Germany was the rst to commercialize the processof decaffeination at the beginning of the 2th century. Since then, there have been severalpatents on decaffeination of coffee. Decaffeination is carried out on green coffee beans Coffee Processing 7 before roasting. This minimizes the loss or alteration of avor that develops only during roasting. Green coffee beans are hard and nonporous in nature, and it is difcult to remove caffeine by extraction. Hence, the beans are rst steamed to cause swelling and softeningof the tissue. The general procedure of decaffeination consists of steaming the green beans and extracting with solvent trichloro ethylene, chloroform, ethylacetate, water, or liquid carbon dioxide (Fig. . Dichloromethane is preferred as solvent in recent times byvirtue of its low boiling point and higher caffeine solubility. However, in view of thesuspected carcinogenic properties of chlorinated hydrocarbons, the trend now is for useof safer solvents such as ethyl acetate, water, and supercritical carbon dioxide. 4.3.9.1 Decaffeination Using Organic Solvents The extraction of caffeine is carried out by using battery of columns, by the countercur- rent method. Green coffee beans are steamed for about half an hour, thereby increasingthe moisture to 4% by prewetting step. The wetted beans are then extracted by usingsolvents such as dichloromethane and ethyl acetate (5, at temperatures between