How is coffee decaffeinated

A.� There are several methods around: extraction using organic chemicals, carbon dioxide and water processing.

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Q.� How does organic solvent extraction work

A.� This was one of the early methods of decaffeinating naturally occurring caffeine products. Basically a chemical was used to either bind the caffeine to it or to filter the caffeine out.

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Q.� How does carbon dioxide processing work

A.� First of all the product is soaked in water, then it is boiled under pressure with carbon dioxide. Under hot, pressurised conditions carbon dioxide acts as a 'magnet' attracting the small caffeine molecules. However the flavour molecules remain intact as theyre larger and so this method retains the flavour better.

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Q.� How does water processing work

A.� This method is used mainly for extracting caffeine from coffee beans.

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Hot water is used to soak out caffeine, along with some coffee flavour, from green coffee beans. After the caffeine is leached out of the material the solution is then passed through a carbon filter for caffeine removal. The water is then returned to the beans for re-absorption of flavours and oils.

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Q.� Do any of these processes remove caffeine completely

A.� No, but they do so below a level so as to be legally classified as 'decaffeinated'.

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Q.� Where does the caffeine come from

A.� Caffeine occurs naturally in more than 60 plants. Coffee beans come from the arabica plant, the Theobroma cacao tree produces the beans that are the main ingredient in chocolate, cola drinks are derived from kola nuts and tea from the Thea sinensis plant.

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Q.� What does caffeine look like

A.� When separated from its sources, caffeine is a white, bitter-tasting powder.

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Q.� Does removing the caffeine spoil the taste of coffee

A.� As caffeine has rather a bitter taste anyway many people don't notice the taste difference although they may notice the lack of punch their decaffeinated drink has.

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Q.� What happens to the removed caffeine

A.� Most of the caffeine removed is then manufactured for use in other products, such as medicines and soft drinks. Many soft drinks don't contain kola nut extracts but the added caffeine comes from one of the various extraction processes.

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by Lisa Cardy