How is decaf coffee made?

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So, you’ve decided to kick your caffeine habit.

Or maybe you’ve just been curious about how they make decaffeinated coffee.

Whatever the reason is, we’re here to answer all your questions about how decaf coffee is made!

Some background

Coffee has been around for hundreds of years, but it was only in the early 1900s that German researchers discovered a method for removing caffeine from coffee beans.

After publishing their findings, the demand for decaf spiked in Europe and America, and it’s remained fairly popular since then.

Today, the most widely used method for making decaf coffee is a chemical solvent technique called methylene chloride—a substance that’s known to be toxic to humans.

With this method being so controversial, many people want to know: what are the other options?

Let’s take a look at how different roasters produce their own versions of decaf (and why some methods might be better than others).

What is caffeine?

Caffeine is a plant-based stimulant chemical compound that occurs naturally in a wide range of plants, including coffee and tea.

It also can be found in guarana berries from Brazil, kola nuts from Africa, yerba mate from Argentina and Paraguay, and the leaves of the xanthine family’s shrubs—which include South America’s yaupon holly.

In its purest form, it can be extracted from coffee beans and sold as white crystals.

These days, though, most pure caffeine is made synthetically.

The human body processes caffeine quickly—some people even notice effects within 15 minutes after drinking coffee or tea with caffeine.

Although everyone metabolizes caffeine differently depending on age (older people process it more slowly) and other factors like medications and health conditions (those taking antidepressants might take longer to process it), typically the effects peak 30 to 60 minutes after consuming it.

How is coffee decaffeinated?

There are three main buckets into which we can use to understand the different decaffeination methods:

  1. Chemical processing
  2. Water processing
  3. Carbon dioxide processing

Chemical processing

The Indirect Solvent Method (Methylene-Chloride)

The most commonly used chemical solvent to decaffeinate coffee is methylene-chloride, a chemical that’s also used as a paint stripper and metal-degreasing agent.

Before you spit out your decaf in disgust, however, it’s considered a safe chemical solvent to use, because it leaves no residue on the coffee beans.

In this process, the coffee beans are heated in hot water to extract flavour, caffeine, and oils.

The beans are then removed from the water and are washed in methylene chloride, a chemical solvent that bonds with the remaining caffeine molecules and separates them from other molecules.

The beans are then heated to evaporate the methylene chloride and the caffeine.

Finally, they are returned to the water to re-absorb the flavour and oils.

The Direct Solvent Method (Ethyl-Acetate)

Ethyl acetate is a natural solvent present in fruits and vegetables.

This is why this method is also called “sugar cane” processing and is often called a natural decaffeination method.

However, the chemical used in this process is reportedly often synthetic.

In the Direct Solvent method, green coffee beans are first soaked in water and then steamed to expand their cells.

Next, they’re soaked in a solution containing Ethyl Acetate, which removes the caffeine.

Finally, the beans are rinsed, dried and shipped.

Water processing

The Swiss Water Process

More recently, the Swiss Water Process has become increasingly popular.

By using an entirely chemical-free process, this method is attractive to those who feel that there are enough chemicals in modern life without adding more to coffee.

In this method, green coffee beans are soaked in hot water to dissolve the caffeine-containing oils.

The water is then filtered through a carbon filter which removes the caffeine and lets the other compounds and oils pass through unharmed.

The beans are then steamed to remove the water from them. This process can be repeated up to ten times before the beans start losing their flavour and oil content too much, after which new beans need to be used in place of these old ones.

The Mexico Mountain Water Process

The MMWP uses water from a protected source and a 1:3 ratio of water to coffee in a long cycle to extract the caffeine.

This removes both caffeine and other soluble compounds from the green coffee beans.

The beans are removed from the solution, which is then filtered of caffeine and then reintroduced to the green coffee seeds, which absorb the soluble materials.

It’s very similar to the Swiss Water Process and both methods claim to remove 99.9% of caffeine.

The Supercritical Carbon-Dioxide Method

The supercritical carbon-dioxide (CO2) method was invented in the late 1980s.

It works because carbon dioxide under high pressure becomes what is called a “supercritical fluid,” meaning it has properties between liquid and gas.

This can be exploited to extract caffeine from coffee beans and is a popular method for decaffeinating green coffee beans.

Here’s how it works:

  • The green coffee beans are soaked in hot water to absorb the caffeine and flavour compounds.
  • The bean mixture is then run through a filter to separate the solids (beans) from the liquid (called green coffee extract).
  • Then, supercritical CO2 is pumped into another chamber with the green coffee extract where they mix together at very high pressures. During this process, the CO2 absorbs all of the caffeine molecules but leaves behind most of the flavour and aroma compounds that give coffee its signature taste and smell.
  • Then, using a depressurising process, all of those caffeine molecules are stripped from the CO2
  • Finally, the green coffee extract which was temporarily stripped of its caffeine content is added back onto the treated beans so that they can dry out like normal.

Decaf Coffee FAQs

Is There Any Caffeine In Decaf?

Yes, there is caffeine in decaf. Since there’s no legal standard for how much caffeine is required to be removed from coffee in order for it to qualify as decaf, the amount of caffeine varies greatly. The FDA in the USA allows up to 97% of the caffeine to be removed from a batch of coffee beans before they can be labelled “decaf.”

Is Decaf Coffee Full Of Chemicals?

Decaffeinated coffee is not full of harmful chemicals. Caffeine itself is a chemical, but it’s not the only one in coffee. Understanding that there are hundreds of compounds in coffee beans gives you a sense of just how much science goes into decaffeination, which involves separating out caffeine from other chemicals and maintaining the integrity of those other chemicals while doing so. Some of these chemicals are considered to be good for you!

Is Decaffeinated Coffee Healthy?

Even without caffeine, coffee beans are naturally high in antioxidants and can help with weight loss and boosting your metabolism. But if you’re looking for a magic potion to help you live forever or cure the common cold, look elsewhere: decaf is simply a way to reap the benefits of coffee without keeping yourself up all night or experiencing other symptoms associated with too much caffeine.

How Is Coffee Decaffeinated Naturally?

Here are two popular methods that are considered natural:
1. The Swiss Water Process (SWP)
2. The Mexico Mountain Water Process (MMWP)

What Are The Side Effects Of Decaf Coffee?

If you’re choosing decaf because of the negative side effects of caffeine, keep in mind that decaffeinated coffee isn’t totally free from these issues. Decaffeinated coffee can still affect your heart rate. Some people who drink decaffeinated coffee may experience sleep disrupton, headaches, and jitters/anxiety—all issues associated with consuming regular caffeinated coffee. Be sure to consult your doctor if you’re switching to decaf because of concerns about the side effects of caffeine.