How is decaffeinated coffee made?

To be able to answer the questions, let's first clarify what caffeine is in the first place and why it can be useful to drink decaffeinated coffee. Caffeine is a naturally occurring compound that also occurs in coffee plants. This is where the name caffeine comes from, as the chemical properties and mode of action of caffeine were first studied in detail using the coffee plant as an example. 

Caffeine works by stimulating the release of the stress hormones cortisol and adrenaline. This increases blood pressure and heart rate. It takes 15 to 30 minutes for caffeine to enter the bloodstream and take effect. Therefore, decaffeinated coffee can be especially useful for people who have elevated blood pressure.

Decaffeinated coffee was first produced in 1903. Ludwig Roselius, a coffee merchant from Bremen and founder of the Kaffee Hag company, developed the process named after him. The reason is very personal: his father died unexpectedly at the age of 59. Ludwig Roselius began researching the health effects of caffeine because doctors suspected his excessive coffee consumption was the cause of his death. 

Roselius first soaked the whole bean in a brine to allow it to expand. To draw out the caffeine, he added benzene to the beans. The Roselius process is no longer used today because the process involved carcinogens..

Decaffeinated coffee is an alternative for people who cannot tolerate coffee ingredients. This way, no one has to give up the pleasure of coffee. But what processes can be used for this and how do they work?

After the water has extracted the ingredients from the beans, the caffeine is filtered out of the water using activated carbon. The caffeine is then removed from the new beans with added water. The unroasted coffee beans are soaked in hot water until all the water-soluble components of the beans, such as caffeine, are in the water. After the water has removed the ingredients from the beans, the caffeine is filtered out of the water using activated carbon. The caffeine is then removed from the new beans with added water. After many repetitions, the result is almost caffeine-free coffee.

The indirect process of decaffeinating coffee beans is similar to the Roselius process. Here, too, the coffee beans are first soaked in water to extract all soluble components of the coffee beans. The caffeine is now extracted from the resulting water-coffee mixture. However, this is no longer done using benzene as in the Ludwig Roselius process, but with dichloromethane or ethyl acetate.

Finally, the decaffeinated water mixture is boiled with newly added beans. Only the caffeine is removed from the new beans, but not the components that are important for the coffee aroma.

In direct decaffeination, coffee beans are first exposed to steam and then soaked in a solvent for several hours. In a further step, the beans are separated from the solvent and dried for several hours to remove any residue.

Decaffeinated coffee can definitely be drunk without hesitation and without danger during pregnancy. Within the EU, according to the regulation, only 0.1% caffeine may be contained in decaffeinated coffee. During pregnancy, 200 mg of caffeine can be consumed without hesitation. A cup of decaffeinated coffee contains about 2-5 mg of caffeine. To be exact, you could drink about 40 cup of decaffeinated coffee during pregnancy.

The methods described require a lot of effort and money to remove the caffeine. In addition, the caffeine is necessary for the plant to deter pests through its bitter taste. But is there a coffee plant that already contains decaffeinated beans?

In fact, scientists discovered a decaffeinated coffee plant in Ethiopia. Since the discovery, various studies have been conducted. However, the results are not yet promising, because the plant does not flower at the same time, which leads to irregular pollination.