The discovery of decaf coffee can be traced back to Johann Wolfgang von Goethe, the famous German author who also had an interest in natural science. In 1819, Goethe gave a box of coffee beans to chemist Friedlieb Ferdinand Runge, asking him to investigate the compound that kept him up at night. A few years later, Runge became the first scientist to isolate and identify caffeine, which led to the eventual development of decaf coffee.

It took almost a century after Runge’s discovery for scientists to figure out how to extract caffeine from coffee while still maintaining the flavor of the beverage. Today, decaf coffee is a popular alternative for those who want to enjoy the taste of coffee without the stimulating effects of caffeine. There are several methods for removing caffeine from coffee beans, including chemical solvents, CO2, and water. In this article, we will explore the different decaffeination methods and answer some frequently asked questions about decaf coffee.

Key Takeaways

• Decaf coffee was discovered by chemist Friedlieb Ferdinand Runge, who isolated and identified caffeine in the early 19th century.
• Scientists took almost a century to figure out how to extract caffeine from coffee beans while maintaining the flavor of the beverage.
• Decaf coffee can be made using chemical solvents, CO2, or water-based methods.

Chemical Solvents, CO2 and Water

Decaffeination is a process that takes place in specialized facilities, and there are different ways of washing caffeine out of coffee beans. Generally, decaffeination involves water-logging coffee beans when they’re still green (before roasting) so that the caffeine inside can be made soluble, meaning that it can be dissolved.

One of the earliest commercially successful decaffeination methods was invented around 1905, by German coffee merchant Ludwig Roselius. Roselius used benzene as a solvent to remove caffeine from coffee beans. 

Benzene is no longer used for decaffeinating coffee because it’s a known carcinogen. Instead, companies that use chemical solvents have switched to other substances, predominantly ethyl acetate and methylene chloride.

The direct solvent decaffeination method involves soaking the coffee beans in hot water to extract the caffeine, then using a solvent such as methylene chloride or ethyl acetate to dissolve the caffeine. The solvent is then removed, and the coffee beans are steamed to remove any remaining solvent residue.

The indirect solvent decaffeination method is similar to the direct method, except that the caffeine is removed from the water using a solvent such as activated carbon filters before the water is returned to the coffee beans.

Another method for decaffeinating coffee is the supercritical carbon dioxide method, which was patented in 1970 by chemist Kurt Zosel. During this process, the coffee beans are placed in a chamber and pressurized with carbon dioxide until it becomes a supercritical fluid. The caffeine is then extracted from the beans using the supercritical carbon dioxide.

The Swiss Water Method is a natural decaffeination process that was first used commercially in the 1970s. In this method, a batch of green coffee beans is soaked in water. That water becomes saturated with all the soluble components found in coffee, including caffeine. 

The caffeine is then filtered out with activated carbon filters, and the uncaffeinated liquid, called green coffee extract, is then added to columns of new, rehydrated, green coffee beans that still have their caffeine. The caffeine migrates from the beans to the green coffee extract as the beans and liquid seek equilibrium, until the beans are almost entirely caffeine-free.

According to Consumer Reports, it can be difficult to figure out the process by which your decaf coffee has been made; there are no specific labeling rules that require companies to disclose this information. However, some coffee companies do advertise their methods. For instance, Blue Bottle flaunts its use of the Swiss Water Process in making its decaf.

The FDA says that decaffeinated coffee might still contain small amounts of caffeine, warning consumers that an 8-ounce cup of decaf typically has 2 to 15 milligrams of caffeine. But that’s still much lower than a caffeinated cup of joe; for comparison, the same amount of regular coffee usually has about 80 to 100 mg of caffeine.

Frequently Asked Questions

What are the methods used to decaffeinate coffee naturally?

There are several methods used to decaffeinate coffee naturally. The Swiss Water Process, also known as the Swiss Water Method, is a chemical-free process that uses water to remove caffeine. Another method is the Carbon Dioxide Process, which uses carbon dioxide to extract caffeine from coffee beans. The Water Process uses water and activated carbon filters to remove caffeine from coffee beans.

Can decaffeinated coffee have negative side effects?

Decaffeinated coffee is generally considered safe to drink and does not have any negative side effects. However, some people may experience mild side effects such as headaches or upset stomachs due to the small amount of caffeine that remains in the coffee.

What distinguishes decaf from regular coffee in terms of health benefits?

Decaf coffee has many of the same health benefits as regular coffee, including reducing the risk of type 2 diabetes, liver disease, and some types of cancer. However, decaf coffee does not provide the same energy boost that regular coffee does due to the absence of caffeine.

How does the water process work to decaffeinate coffee?

The Water Process uses water and activated carbon filters to remove caffeine from coffee beans. First, the beans are soaked in hot water, which extracts the caffeine and other flavor compounds. The water is then passed through activated carbon filters, which absorb the caffeine molecules but leave the flavor compounds intact. The beans are then soaked in the decaffeinated water, which reabsorbs the flavor compounds and leaves behind decaffeinated coffee beans.

Are there any chemical-free processes for making decaf coffee?

Yes, the Swiss Water Process and the Carbon Dioxide Process are both chemical-free methods for making decaf coffee. The Swiss Water Process uses only water and activated carbon filters to remove caffeine, while the Carbon Dioxide Process uses carbon dioxide to extract caffeine from coffee beans.

What is the purpose of drinking decaf coffee if it tastes similar to regular coffee?

The purpose of drinking decaf coffee is to enjoy the taste and aroma of coffee without the stimulating effects of caffeine. Decaf coffee can be enjoyed at any time of day, even in the evening, without disrupting sleep patterns. It is also a good choice for people who are sensitive to caffeine or who want to reduce their caffeine intake.