How Do They Make Decaffeinated Coffee

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Decaf sounds like a good idea, especially to those of us with caffeine sensitivity. The truth is that while caffeine lovers get a nice jolt of energy, caffeine leaves some of us shaking in our boots. That uneasy, jittery feeling is the reason more coffee drinkers opt for decaf.

On the other hand, some coffee connoisseurs wouldn't be caught dead with a cup of decaf coffee. It has a bad rap for being both unnatural and lacking the savor of caffeinated coffee. However, there is a growing number of coffee drinkers who are forced to drink decaf (for health reasons) or just want a healthier alternative.

Speaking of health, those of us who are more health conscious are also concerned about the source of this so-called unnatural coffee. How do they make decaffeinated coffee anyway? There are a few processes used, some of which can be adopted at home to make your own decaf.

What Is Decaffeinated Coffee ?

With this type of coffee, the caffeine that is naturally included in coffee beans is removed. Actually, only most of it is removed. Typically, you can expect about 97% of the caffeine to be removed in actuality.

There are a few processes that are used to extract caffeine from coffee. It's not as simple as it sounds. There are thousands of other chemicals in coffee that contribute to its health benefits, taste and smell that have to be preserved during the process.

The earliest form of caffeine extraction, called the Roselius Process, involved using the solvent benzenes to extract caffeine. Though effective, benzene was later found to be a human carcinogen. There are three major methods of caffeine extraction used today.

  • Solvent-based methods

  • CO2 process

  • Swiss Water Process

Solvent-based methods involve introducing the coffee beans to a chemical to remove the caffeine. The most common chemicals used are ethyl acetate (fruit ether) and methylene chloride

Is Decaf Totally Free Of Caffeine?

There have been multiple occasions in which I thought the barista surely confused my order and served me caffeinated instead of decaffeinated coffee. I thought, "why do so many baristas on separate occasions confuse decaf with caffeinated?" It turns out that my sensitive system was reacting to the caffeine in decaf.


Yep, you heard right. The truth is it's a rarity to find 100 percent decaf because it's extremely difficult for any of the processes mentioned above to extract all the caffeine from the coffee beans.

An average 8-ounce cup of decaf joe contains around 7 milligrams of caffeine. This is nothing compared to between 70 and 140 milligrams in a regular cup of caffeinated coffee. That's a big difference, but the effects such small amounts could have are relative to the individual.

As I mentioned, those few milligrams do not go undetected in my digestive system. This means decaf can present similar side-effects as caffeinated coffee. Side-effects can include, but may not be limited to the following:

  • Racing heart
  • Headache
  • Insomnia
  • Diarrhea
  • Dysphoria
  • Anxiety
  • Jitters
  • Nausea
  • Upset stomach

Thanks to one source, I found out that my typical go-to spot for coffee wins the most caffeinated decaf award. To be specific, a 10 to 12 ounce cup contains 20 milligrams of caffeine. This amount is more than double the caffeine content found in the competitors' decaf coffees.

Fortunately, it is said that the Swiss Water process is the only decaffeination process that removes 99.9 percent of caffeine. Coffee decaffeinated using this process is usually labeled as Swiss Water decaf, so it's easier to identify.

Is Decaf Healthy?

Over the years, studies have been conducted to determine if decaf poses any health threats. Fortunately, it doesn't pose any more of a threat than regular coffee. However some chemicals associated with roasting and decaffeinating coffee might be a cause for concern.

How Is Coffee Decaffeinated Good For You?

Coffee beans contain thousands of chemicals besides caffeine, many of which are very good for your health. Therefore, while decaf is free (or mostly free) of caffeine, it still maintains tons of health benefits thanks to the other chemicals left behind during the decaffeination process.

For one, decaf, just like regular coffee, is loaded with antioxidants. These substances reduce free radicals that can lead to cancer, heart disease and type 2 diabetes.

Decaf also contains chemicals that protect against neurodegenerative disorders, liver damage and aging. Furthermore, it contains some essential minerals, like magnesium and potassium.

Lastly, the fact that it's caffeine free could actually contribute to less health risks. For example, one study found that caffeine can increase estrogen levels in both human and animal study subjects. Heightened levels of estrogen have been linked to endometriosis, ovarian cancer, breast cancer.

It is worth noting that there are usually less beneficial compounds in decaf than regular coffee because other chemicals are lost during the decaffeination process.

How Is Coffee Decaffeinated Bad For You?

Numerous studies have found that decaf has no known health risks other than those associated with caffeine, which most decaf does actually contain. Any risks that decaf might have separate from regular coffee lie in one of the decaffeination methods and the roasting process.

One of the solvents used to remove caffeine, methylene chloride, has been found to be highly toxic. Inhalation of the chemical can lead to central nervous system side-effects that include compromised attentiveness and hand-eye coordination. Only mild exposure can also cause irritability, headaches, lightheadedness, coughing, wheezing and drowsiness.The FDA will only approve coffee that contains .001 percent or less of the chemical .

A separate health concern is a by-product of the roasting process, called acrylamide. This chemical has been named as carcinogenic in human beings and is classified as a type 2A carcinogen.

In addition to the carcinogenic effects, those exposed to the chemical in industrial manufacturing can also experience a compromised nervous system.

Fortunately, the 178 micro-grams per kilogram in roasted coffee is much less than the amount in instant coffee and some coffee replacements. More so, studies found that although acrylamide is a carcinogen, coffee itself has been found to reduce cancer risk. Therefore, the effects of acrylamide don't seem to be much of a threat.

Most coffee varieties are roasted, including decaffeinated and caffeinated coffee.This means that they each can pose the same potential risks of exposure.

Overall, decaf appears to be generally safe to consume. Perhaps it's even more safe than regular coffee since it doesn't have as much caffeine.

Decaf Vs. Non-decaf Coffee, Which Is Tastier?

Coffee has numerous compounds, some of which contribute to its distinctive smell and taste. As mentioned earlier, the decaffeination process can remove some of the chemicals that give coffee its signature taste. But to what extent is decaf taste different from caffeinated coffee?


Some coffee stewards swear that decaf has a dull, watered down taste. That's probably due to the decaffeination process.

One study found that participants who could differentiate between decaf and caffeinated did so based on the level of bitterness. The caffeinated coffee seemed to have more of a bitter taste .

Green coffee beans contain chemicals called chlorogenic acid lactones. The more the coffee beans are roasted, the more the chlorogenic acid lactones will develop a bitter flavor. If some of those compounds are lost during the decaffeination process, then it makes sense that it would also lose some of its bitterness.

One particular vlogger tested the decaf and caffeinated medium roast versions of a grocery store brand. His conclusion was that they both were preferable in their own way. Like many other coffee drinkers can attest to, the caffeinated coffee had a stronger taste while the decaf was more mild.

He concluded that the decaf would taste better black, without a lot of sugars and cream since the taste was mild. However, with additions, it might taste watered down. On the other hand, the caffeinated coffee's strong taste could remain strong with added ingredients.

For those of us who don't drink caffeinated coffee that much, the tastes don't seem to be much of an issue. For example, I rarely drink coffee straight, and my favorite is decaf lattes. The combination of the various ingredients are more important than the strong, bitter taste that some coffee drinkers prefer.

How To Decaffeinate Coffee Yourself

Earlier, I introduced you to the three main ways to professionally remove caffeine from coffee beans. Unless you're in the business of coffee manufacturing, own a coffee shop or just want to spend a bunch of time and money experimenting, those methods aren't that suitable to do at home.

So, I did a little research to find the easiest and least expensive way to decaffeinate coffee at home. The method requires using sodium carbonate and Dichloromethane to extract caffeine from ground coffee. Here are the steps for this method of decaffeination.

Sodium Carbonate And Dichloromethane Method

For this method, you will need the following tools and ingredients:

  • 60 milliliters of distilled Water
  • Coffee Filters
  • 10 grams of caffeinated coffee
  • 40 milliliters of Dichloromethane
  • 4 grams of sodium carbonate
  • Watch glass
  • Glass beakers or flask
  • Glass funnel

Step 1: Convert Sodium Bicarbonate To Sodium Carbonate

Sodium bicarbonate is just a simple name for baking soda.

Pour the desired amount into a heat-resistant pot, such as stainless steel.

Step 2: Heat The Sodium Bicarbonate

Heat the solution until it reaches at least 200 degrees Celsius (medium to high heat).

Stir continuously until gas bubbles form.

Continue to stir. When you no longer see the gas bubbles, cover the solution. 

Step 3: Boil Coffee, Sodium Carbonate And Distilled Water

Add about 10 grams of ground coffee, 4 grams of sodium carbonate and 60 milliliters of distilled water to a beaker.

Cover the mixture with a watch glass to prevent the water from escaping.

Boil for at least 15 minutes. Allow the mixture to cool.

Step 4: Gravity Filtration

This is one of the oldest and simplest methods of filtration. The substance to be filtered is poured into a flask or beaker that has folded filter paper resting at the neck of the flask or beaker. The filter paper catches molecules that are larger molecules or solids while the smaller molecules flow downward into the container by way of gravity (http://www.chem.ucalgary.ca/courses/351/laboratory/filtration.pdf).

Place a coffee filter at the top of the beaker or flask.

Pour the mixture into the coffee filter.

Eventually, you will see that the solids are captured by the filter while the rest is in the container.

Next, add 100 milliliters of boiling hot distilled water.

Cover the mixture with a watch glass to avoid heat loss.

Shake the glass lightly to speed the filtering process.

Step 5: Transfer Remaining Coffee To Funnel

Slowly pour the liquid mixture from the filtering process into a funnel.

Next, add 15 milliliters of dichloromethane.

Shake the mixture very gently.

You will eventually have two layers, a bottom layer with the dichloromethane and caffeine and the top layer of decaffeinated coffee.

Drain the bottom layer out.

Your finished product will be homemade decaf coffee.

In Summary

Decaf coffee has a bad reputation among coffee connoisseurs. Many claim the taste is sub par, and some just see it as unnatural. However, there are many benefits of decaf.

Despite the fears, it's very good for your health, and it can have a pleasing taste as well. If fact, studies show that it might just be even healthier than caffeinated coffee.

However, decaf is much less available than caffeinated coffee. Fortunately, you may be able to turn your favorite caffeinated coffee into decaf by using the fairly simple extraction method above. Have you tried DIY caffeine extraction? Let us know your thoughts in the comments below.