What Is the Swiss Water Process? Understanding Decaf Coffee

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With so many coffee enthusiasts, coffee was not going down the drain because of its caffeine content. The rise of decaf coffee is exponential with the findings of caffeine health risks. People who try to cut back on their caffeine intake or have health issues related to caffeine flocked to decaf coffee.

Coffee beans naturally contain caffeine. One of three methods is used to decaffeinate coffee: the swiss water process, carbon dioxide, or methyl chloride.

Many people avoid the carbon dioxide and methyl chloride methods of decaffeinating coffee because of the added chemicals. Cutting out the carbon dioxide and methyl chloride methods leaves the Swiss water process to decaffeinate coffee.

So, what is the Swiss water process?

Swiss Water Process, What is it?

The Swiss water process leaves coffee 99.9% caffeine free. It is a chemical-free decaffeination process to remove caffeine. Water is combined with heat and time to decaffeinate coffee naturally. The short answer to how the Swiss water process works is diffusion. The green coffee beans soak in the green coffee extract that contains all water-soluble compounds.

While the ingredients of the Swiss water process haven’t changed, scientists are constantly working on perfecting the process. They tweak the decaffeination process to leave the best-tasting, full-flavored coffee bean possible. The goal is coffee beans that taste like regular coffee without caffeine.

In our test, we tried 12 decaf instant coffee and found that Swiss water processed decaf brands generally tasted quite similar to caffeinated coffee.


The History of the Swiss Water Decaf

The Swiss water decaf coffee process was discovered in the 1930s by Ludwig Roselius in Schaffhausen, Switzerland. The Swiss water process is a 100% chemical-free, organic way to decaffeinate coffee beans. The Swiss Decaffeinated Coffee Company Inc commercialized the decaffeination process when they began in 1988. [1]

Ludwig Roselius, a German coffee merchant, discovered the first chemical-free coffee decaffeination process. This process was named after him and is known as the Roselius Process. Roselius was on the quest for a healthier way to decaffeinate coffee because he believed the high consumption of coffee decaffeinated with benzene was the cause of his father’s premature death.

The Swiss water decaffeination process was developed in 1933 and commercialized in 1980. The process was inefficient at this point, resulting in uneven batches of green coffee beans that proved hard to roast. In 2007, it was redeveloped into its current stage. The Swiss water decaffeination process yields consistent, high-quality decaffeinated coffee with the same flavor as regular coffee.

What Is the Difference Between Decaf and Swiss Water Decaf?

The Swiss water process is one of a few ways to decaffeinate coffee. Other ways to decaffeinate coffee include adding chemicals like methylene chloride, carbon dioxide, or ethyl acetate to cause a chemical reaction with the caffeine to remove it from the green coffee beans.

As you can imagine, coffee consumers hear the word chemicals and avoid those processes. Adding chemicals to your food can cause harm to your body because your body doesn’t know how to process these chemicals.

Methylene chloride is a solvent with a low boiling point. It is used to indirectly dissolve the caffeine by bonding with caffeine in the water of green coffee beans that have been soaking for hours. The caffeine-filled solvent is skimmed from the solution, and the water is put back in with the green coffee beans. This process repeats until 97% of caffeine is removed. [2]

The carbon dioxide method uses liquid carbon dioxide in place of chemical solvents. Soaked coffee beans are placed in a pressurized vessel with carbon dioxide, which dissolves the caffeine.[3]

Ethyl acetate is a solvent derived from fermented sugarcane. This chemical is known for its sweet taste and properties that extract caffeine from steamed green coffee beans.

How Does the Swiss Water Process Work?

The Swiss water process uses diffusion to extract caffeine from green coffee beans naturally.

  1. Super-saturated green coffee extract (GCE) is saturated with the water-soluble compounds of green coffee, minus the caffeine.
  2. Green coffee extract is introduced to a batch of green coffee beans.
  3. The caffeine in the green coffee wants to homogenize the mixture, so they go to the low-concentration areas, which is the green coffee extract.
  4. The matching properties of the green coffee beans and green coffee extract do not diffuse, leaving only the caffeine to diffuse.
  5. All of the flavors of the coffee beans are retained because the only thing moving is the caffeine. It moves from the green coffee beans into the green coffee extract.
  6. The green coffee extract is removed, leaving a caffeine-free green coffee bean that tastes the same as a regular coffee bean!

What Is Green Coffee Extract (GCE)?

Green coffee extract is the extract from green coffee beans, and its primary use in commercial processing is in the Swiss water process to decaffeinate coffee. It also has weight-loss properties and is used as a supplement in weight-loss products.

The green coffee extract comes in liquid and tablet form. The liquid form is used in the Swiss water process. This allows more surface area for the green coffee beans to interact with the extract and remove more caffeine.

Benefits of the Swiss Water Process

The Swiss water decaffeinated coffee is great because it uses its own ingredients to extract the caffeine from green coffee beans. The use of a simple scientific process allows the caffeine to diffuse from a high-concentration area of the green coffee beans into a low-concentration area of the green coffee extract.

Because green coffee extract and green coffee beans have the same properties other than caffeine content, the only thing that changes is the caffeine. The lack of harmful added chemicals leaves a healthier finished product.

What Makes the Swiss Water Process Different from Other Decaf Methods?

The Swiss water process differs from other decaffeination methods because it does not use chemicals as a solvent. In other ways, harmful chemicals are added to your coffee beans to react with the caffeine and dissolve it into the liquid solvent. Scientists try to remove the coffee beans’ chemicals by either vaporizing or cleaning, but a trace amount is left. This trace amount of chemicals can build up and cause harm to your body.

The Swiss water process does not require chemical reactions that change the structure of the coffee beans or caffeine molecules. Instead, the caffeine is simply moved from one medium to another by diffusion.


If you still have questions about the Swiss water process, don’t worry! Others have frequently had the questions below.

Is the Swiss water process healthy?

Yes, the Swiss water process is healthy and does not add harmful chemicals to the green coffee beans as other decaffeination processes do.

Does the Swiss water process use chemicals?

No, the Swiss water process does not use chemicals. Instead of chemicals, the Swiss water process uses green coffee extract and diffusion to remove the caffeine.

What happens to caffeine after the process?

The caffeine is trapped in the green coffee extract. The whole caffeine molecules are disposed of in the green coffee extract.

What happens to the water after the process?

The water contains caffeine. The water is disposed of to get rid of the caffeine.

How much caffeine is in Swiss water coffee?

Swiss water process coffee is 99.9% caffeine free, leaving 0.1% caffeine in the coffee beans.


[1] Know the facts before you choose your decaf – https://drwakefield.com/swiss-water-decaf-process-coffee

[2] Decaf Methylene Chloride (MC) Process – https://www.interamericancoffee.com/decaf-methylene-chloride-mc/

[3] What is the CO-2 Decaf Method? – https://library.sweetmarias.com/co-2-decaf-method/

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Chris Clark

Chris Clark is the co-founder and chief content editor of BrewCoffeeHome.com. With a passion for all things java, Chris has been a coffee blogger for the past 3 years and shares his expertise in coffee brewing with the readers. He's a hands-on expert, loves testing coffee equipment, and has written most of the in-depth reviews featured on the site. When he's not whipping up delicious drinks or experimenting with the latest coffee gadgets, Chris is exploring the local cafe.