The Decaffeination of Coffee
- By Bill Weston
- Published 11/24/2011
- Coffee
- Unrated
Decaffeination is the process of removing caffeine from coffee beans, cocoa, tea leaves and other materials which contain caffeine. Some beverages are often referred to as "decaffeinated", when they actually don't contain any caffeine in the first place, making them more accurately described as "uncaffeinated". Even after "decaffeination", caffeine-containing drinks usually retain 1-2% of their original caffeine content.
Caffeine is a bitter crystalline alkaloid that acts as a stimulant, found in the seeds, leaves and fruit of various plants, where it acts as a natural pesticide. Caffeine wards off drowsiness in humans, offering alertness and energy. It's the world's most widely-consumed psychoactive drug, with 90% of North Americans consuming caffeine on a daily basis. Caffeine can be toxic at high doses, but typical consumption poses no known health risks to consumers.
Various methods can be used to decaffeinate coffee. It usually happens with unroasted coffee beans, when they are steamed and rinsed with a solvent which extracts the caffeine while leaving other natural chemicals untouched within the beans. This process can be repeated up to a dozen times, or until it meets international standards.
The International Standard demands no more than 3% of the caffeine remaining, while the EU standard demands that 99.9% of the coffee beans should be free of caffeine
. With coffee beans containing over four hundred different chemicals which play an important part in the aroma and taste of the beans, it can be challenging to remove the caffeine while leaving these other important chemicals in place.
Swiss Water Decaffeination Process
The Swiss Water Process of decaffeination was developed by the Swiss Water Decaffeinated Coffee Company, and involves a batch of green coffee beans to be soaked in hot water. This releases the caffeine and coffee solids into the water, when the beans are discarded. This water is then passed through a carbon filter which traps caffeine but allows coffee solids to pass. Additional beans are added to the resulting "green coffee extract" (or GCE), and the process is repeated, filtering out all the caffeine until the beans are 99.9% caffeine-free. These beans are then dried and distributed.
Direct Decaffeination Method
In the direct decaffeination method, coffee beans are steamed for thirty minutes and rinsed with dichloromethane or ethyl acetate for several hours. The solvent is drained away and the beans are then steamed again for several hours to remove all traces of the solvent.
Indirect Decaffeination Method
In this method of decaffeination, the coffee beans are soaked in hot water for several hours. The beans are then removed and dichloromethane or ethyl acetate is used to extract the caffeine from the liquid. Sometimes this process is known as "water-processed", although chemicals are used.
Caffeine is a bitter crystalline alkaloid that acts as a stimulant, found in the seeds, leaves and fruit of various plants, where it acts as a natural pesticide. Caffeine wards off drowsiness in humans, offering alertness and energy. It's the world's most widely-consumed psychoactive drug, with 90% of North Americans consuming caffeine on a daily basis. Caffeine can be toxic at high doses, but typical consumption poses no known health risks to consumers.
Various methods can be used to decaffeinate coffee. It usually happens with unroasted coffee beans, when they are steamed and rinsed with a solvent which extracts the caffeine while leaving other natural chemicals untouched within the beans. This process can be repeated up to a dozen times, or until it meets international standards.
The International Standard demands no more than 3% of the caffeine remaining, while the EU standard demands that 99.9% of the coffee beans should be free of caffeine
Swiss Water Decaffeination Process
The Swiss Water Process of decaffeination was developed by the Swiss Water Decaffeinated Coffee Company, and involves a batch of green coffee beans to be soaked in hot water. This releases the caffeine and coffee solids into the water, when the beans are discarded. This water is then passed through a carbon filter which traps caffeine but allows coffee solids to pass. Additional beans are added to the resulting "green coffee extract" (or GCE), and the process is repeated, filtering out all the caffeine until the beans are 99.9% caffeine-free. These beans are then dried and distributed.
Direct Decaffeination Method
In the direct decaffeination method, coffee beans are steamed for thirty minutes and rinsed with dichloromethane or ethyl acetate for several hours. The solvent is drained away and the beans are then steamed again for several hours to remove all traces of the solvent.
Indirect Decaffeination Method
In this method of decaffeination, the coffee beans are soaked in hot water for several hours. The beans are then removed and dichloromethane or ethyl acetate is used to extract the caffeine from the liquid. Sometimes this process is known as "water-processed", although chemicals are used.
Bill Weston
Bill Weston writes on a number of subjects including flavia coffee machines, coffee vending machines and Alterra coffee.
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