Methods for removing caffeine from coffee.

If you're a fan of decaffeinated coffee, you should toast Friedlieb Ferdinand Runge the next time you make a pot.

The poet and statesman Goethe, who was also a keen science scholar, had heard of the 19th-century German chemist Runge. It was no secret to Goethe that Runge had done some groundbreaking research on belladonna, or deadly nightshade. The compound that, if ingested, causes the eye muscles to dilate had been identified by Runge.

After receiving a case of coffee beans as a gift, Goethe requested an analysis from Runge. Caffeine, which Runge discovered, is now one of the most widely used drugs.

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Caffeine can be found in a variety of other beverages and foods, most notably tea and chocolate, but it is most closely associated with coffee. It's a reliable wake-up call for students cramming for exams, workers on nightshifts, and anyone else in need of a pick-me-up because it's a stimulant and an appetite suppressant.

Nonetheless, caffeine also has some negative effects.

Anxiety, insomnia, diarrhea, profuse sweating, a rapid heart rate, and trembling muscles are all possible side effects. There are many people who can't enjoy coffee because of the negative effects of caffeine.

Can caffeine be taken out of coffee? The aisles of any supermarket will tell you the answer is yes, but getting there isn't as easy as it sounds.

Ludwig Roselius, the founder and CEO of Kaffee HAG, another German company, was the first to develop a functional decaffeination process. Caffeine decaffeination was accidentally discovered by Roselius. Shipments of coffee in 1903 had been flooded by seawater during transport, removing the caffeine but not the flavor. Caffeine was previously extracted from coffee beans by hand, but Roselius devised an industrial method to steam the beans with various acids and then use the solvent benzene to extract the caffeine. The first decaf coffee appeared.

As it turned out, benzene could cause cancer, so scientists set out to find alternatives that would allow them to remove the caffeine without altering the beans' flavor.

British Coffee Association director Chris Stemman claims that many of the earliest decaffeination methods are still in use today. However, it's not as simple as you might think.

Stemann claims that "it isn't done by the coffee companies themselves." "There are companies that specialize in decaffeinating coffee." Many of these corporations have headquarters in the Americas, Europe, and Canada.

It may seem like the easiest option to simply roast the coffee beans, grind them into the appropriate powder (espresso, filter, or instant), and then start the decaffeination process. That's not the case, according to Stemman.

Green coffee is processed in this way before being roasted.

Somewhat like straw flavor would result if you tried to decaffeinate roasted coffee, the author argues. This is why the number 99 Today, the green coffee stage accounts for 9 percent of all decaffeinated brews. ”

Soaking coffee beans in a solvent, most commonly methylene chloride or ethyl acetate, is the most common method of decaffeinating coffee. Methylene chloride has many practical applications, including those of a paint stripper, degreaser, and caffeine remover.

Nail polish remover is made from ethyl acetate, a natural fruit ether that smells like pear drops and is derived from acetic acid (the main component of vinegar).

Soaking the beans in water and then covering them with a solution containing one of these solvents is the standard procedure. Solvent then extracts the caffeine.

The solvent-infused water is recycled until it is saturated with compounds that taste and smell like coffee but lack the caffeine and solvent found in the beans. By this point, the beans have lost very little of their flavor due to their immersion in a concentrated coffee essence.

Although it may seem counterintuitive to soak coffee beans in solvents, both of these chemicals are perfectly safe to use. In 1985, the US Food and Drug Administration declared methylene chloride to pose "essentially non-existent" danger to human health. (The FDA allows for up to 10 ppm of residual methylene, but typically only 1 ppm is used in coffee decaffeination solutions.)

Water is used in two additional processes. Swiss Water processing involves soaking the beans in water, then filtering the resulting caffeine-rich solution (rich in flavor) through activated carbon to extract the caffeine. In the 1930s, the process was pioneered in Switzerland; by 1979, it had made its way into commercial use. In part, its success can be attributed to the fact that it was the first solvent-free decaffeination technique.

Stemman claims there is a second method that makes use of "super critical carbon dioxide." Soaked beans are placed in an extractor made of stainless steel, the lid is screwed on tight, and liquid carbon dioxide is forced into the chamber at pressures of up to 1,000 pounds per square inch. Similar to the Swiss Water process, the carbon dioxide binds to the caffeine molecules, extracting them from the raw coffee bean. The pressure is reduced and the gas is removed, isolating the caffeine in a new chamber.

A major flaw, in Stemman's opinion, undermines the ingenuity of the approach. "It can be very costly. ”

Instant coffee's popularity led to a rise in decaf consumption, according to Stemman. However, instant decaf coffee was not an instant hit in its early iterations.

The United Kingdom "really was a nation of instant coffee drinkers" 20 or 30 years ago, he says. One thing instant coffee didn't have was a coffee flavor. The effects of decaffeination were even more unpleasant. ”

Stemman argues that the rising demand for specialty coffee has prompted manufacturers of both caffeinated and caffeine-free instant beverages to experiment with new methods of flavor enhancement.

As one expert put it, "decaffeination can be a complicated piece of chemistry, which is why there are these very sophisticated companies doing it." ”

Little was made of the fact that decaffeination turned 100 in 2006. Even though decaf coffee has improved in quality, fewer people are drinking it. In the 1980s, about 15% of coffee drinkers in the UK preferred decaf beverages; today, that number has dropped to around 8%.

Is Stemman a decaf guy? In most cases, "no," because if I don't want caffeine, I simply don't drink coffee or tea. ”

Yes, there's something else A substantial amount of caffeine can be removed by each of these techniques, but there is no such thing as a caffeine-free beverage. In order to completely avoid caffeine, it's best to stick to beverages that have never contained any.

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