How Decaf is Made
The science is constantly developing. Each year we gain a better understanding of the intricate connection between nutrients and health. Today we know that caffeine’s effect is highly personalized and genetically predetermined. Some people find out that they should drink no more than 1 cup of coffee per day. What should they do?
We advise choosing other drinks: tea and cocoa. Or you can drink decaf. Decaf is short for decaffeinated coffee. It conserves the taste and antioxidants of coffee while preserving the cardiovascular system of consumers.
In fact, a cup of decaf still contains a certain amount of caffeine. According to USDA standards, a coffee should lose no less than 97% of its caffeine to be considered decaf. In such a way, a regular americano cup has 2 to 5 mg of caffeine.
Ludwig Roselius was the first to produce decaf on a commercial basis. His technology included using benzene to extract caffeine from the coffee. Benzene isn’t used anymore because of its cancer-inducing properties.
Currently, there are four ways to make decaf.
Solvent process
This process includes using solvents that help to extract caffeine from the beans. Almost 70% of all decaf is made this way. There are direct and indirect solvent processes.
During the direct process coffee beans are steamed for 30 min to open their pores. After that, they are submerged in a solvent for 10 hours to extract almost all caffeine. Then the solvent is washed from the beans by a large quantity of water, and beans are steamed again to extract any remaining solvent.
Many people treat the solvent process with distrust or even fear. No big surprise: coffee makers had previously used highly toxic substances as solvents. Nowadays they use chloromethane and ethyl acetate that are completely harmless for our health in the provided doses.
FDA has found out that any potential harm from chloromethane is so low that it’s ‘virtually non-existent’. Agency allows up to 10 particles per million (ppm) of chloromethane. Only 1 ppm of this substance is left after the process is over.
Those who choose decaf and want to consume less ‘synthetic’ substances often prefer drinks decaffeinated by ethyl acetate. This substance is often found in ripening fruits, and many consider it to be more natural, so the producers often label this coffee as ‘natural decaf’. However, as it’s expensive to extract ethyl acetate from plants, coffee makers usually use synthetic one.
No matter the solvent, your coffee most likely won’t contain these substances as they are unstable at the temperatures of coffee roasting.
Swiss Water Process — SWP
During the 80s a Swiss company Coffex S.A. has discovered a new revolutionary method of decaffeination that doesn’t require solvents and allows for 99,9% of caffeine extraction. This method was named Swiss Water Process.
This method uses two processes: solution and osmosis. Green coffee beans are submerged in hot water. It absorbs caffeine, aromatic substances, and oils. The beans are then discarded.
After that, the carbon fiber filter separates large molecules of caffeine from other substances, which allows us to get the green coffee extract. The next batch of coffee beans is submerged in this extract instead. Only caffeine leaves the coffee now, as oils and aromatic substances are already in the solution.
CO2-extraction
This is the most modern method of decaffeination. In this method liquid CO2 extracts caffeine instead of solvents. Under the high pressure, CO2 flows through the coffee beans in the extractor and transports caffeine to the next container. The gas depressurizes, loses caffeine and is ready to be used again.
This process reduces the coffee mass, so it isn’t used for rare and exclusive coffee. However, mass coffee producers use it for large quantities of beans.
Caffeine-free coffee types
Researchers have discovered more than 3000 coffee plants and found three species that lack caffeine. These plant varieties lack caffeine synthase — an enzyme that transforms theobromine to caffeine. This coffee isn’t on the market yet, as plants need to go through regulatory evaluations. We also don’t know yet how this coffee would taste, and if it’s viable to grow these plants.
Modern methods for making decaf are fully safe for your health but, depending on the process, the coffee may lose some of its incredible flavors. Also, decaffeination requires additional resources, so decaf is usually more expensive than regular coffee. Now, we are waiting for the time when the genetic engineering will make caffeine-free coffee growing possible. And what are you waiting for?
Sources
The Guardian: Scientists discover decaf coffee bean
Plant biochemistry: A naturally decaffeinated arabica coffee
