Deconstructing Decaf Coffee: What, Why, and How

There’s generally a love-hate relationship when it comes to decaf coffee. For some, it’s the only way they can enjoy a delicious bean juice. For others, it’s simply an abomination. Others might be somewhere in the middle, drinking regular caffeinated coffee in the morning but switching to decaf after a certain time or after coffee number X.

There are different reasons people might reach for decaf coffee, from personal preferences to a desire to avoid certain effects (or side effects) of caffeine while still enjoying a delicious and healthy beverage. In this article, we take a thorough look at decaffeinated coffee, starting with what caffeine is, its effects, what decaf means, the ways caffeine can be removed from coffee beans, and potential reasons why decaf might be a great option sometimes. So grab yourself a cup and let’s jump in (to the article, not the cup).

What is caffeine?

Caffeine is a molecule that occurs naturally in around 30 different plants, the most famous of which are:

• Coffee
• Tea
• Cacao
• Kola nut
• Yerba mate
• Guarana
• Guayusa

Caffeine is synthesised in these plants from smaller organic molecules - like tiny natural chemistry labs. This pathway actually evolved in these plants over millions of years because caffeine works as an insecticide, deterring pests from eating the plants. So while it may have been created as a defense mechanism for plants, eventually we humans learned to extract this natural compound from various plants and appreciate it for other reasons…

[By the way, we’ve written an entire article dedicated to caffeine – for more dirty details, see here]

What does caffeine do to us?

In humans, caffeine acts as a central nervous system stimulant, promoting wakefulness and alertness. So, besides the amazing taste of a well-prepared coffee, caffeine is a major factor for many of us in why we love coffee so much. It fuels us through our daily tasks, motivates and excites us to get up and at it, and helps us push when we just need to stay awake a bit longer. Technically speaking, caffeine does not ‘give us energy,’ but rather works by blunting our natural feelings of tiredness. Cool, right? (see that article linked above to read more about that)

But caffeine is in fact a psychoactive drug, and like all drugs, it has side effects in addition to its benefits. So naturally, some people, for various possible reasons, may wish to avoid or cut down on their caffeine consumption. If those same people just really love coffee, well, what are they to do? We already know the answer to that, since we are reading an article about decaf. So let’s take a brief look at some of the shadow sides of caffeine.

“Why in the world would someone want to avoid caffeine? Caffeine is awesome.”

We know, we know. But we also understand that not everything is for everyone, and there are natural limits to the ‘good’ of things. Try drinking 3 double espressos just before going to sleep tonight, and maybe you will have a newfound understanding of this perspective. We’re joking, don’t try that–it’s been demonstrated that sleep quality is generally worse when there are raging amounts of caffeine in your system, even if you feel like you slept well.

While many of us love the jolt of the caffeine from a good coffee, for others that jolt is delivered in the form of pure anxiety. Some may find they can’t sleep at night even if they drink coffee in the morning. We all have different levels of sensitivity to substances, and some people are particularly sensitive to caffeine. Some medications can also affect how caffeine is processed by the body, meaning that a cup of joe might keep you up for 3 times longer than expected. Other mild possible side effects of caffeine can include trouble sleeping or taking longer to fall asleep, anxiety, jitteriness, restlessness, nausea, and increased heart rate.

In general, it appears that consuming up to 400 mg of caffeine daily (about 3 to 5 typical coffees) is safe for those who tolerate it well. But caffeine can stay in our body (in relatively high amounts) for anywhere from about 5 to 16 hours, depending on individual metabolism and whether we are taking certain medications or smoking tobacco. For example, smokers process caffeine more quickly, while pregnant women process it particularly slowly. For those who have trouble sleeping, find their anxiety increases, or simply feel too stimulated, stopping caffeine entirely or stopping its consumption earlier in the day can help.

At the same time, we all love a good cup of coffee. There are many apparent health benefits of coffee, and coffee–decaf included–is packed full of antioxidants. So, one solution is to simply drink coffee, but just skip the caffeine. Thanks to some major advancements over the last decades, we can now find amazing decaf coffees, providing us with tasty beverages packed full of antioxidants, pleasure, and joy, but low in stimulating effects. Win-win!

We actually have 3 decaf coffees in stock right now, letting you explore the glorious flavours of the specialty coffee world without the caffeine. Check them out below, order them all to your house immediately, and then keep reading to find out how they became decaf!

Copycat Colombia, Cauca / Washed / Colombia, Castillo & Caturra

Bravado Colombia, Quindio / Natural / Pink Bourbon

Quindio Colombia, Quindio / Natural / Castillo

What is decaf?

Decaf is short for decaffeinated, which already tells us something about decaf coffee–it’s not naturally caffeine-free, but rather the caffeine is removed! There are actually a few naturally decaf coffee species–think of them like cousins of our beloved Coffee arabica–which have been discovered recently. These are not likely to replace decaf coffee; since caffeine serves to protect the plant from certain pests, these caffeine-free plants may not be robust enough for mass production. So, at least for the time being, decaf coffee is obtained by removing the caffeine from regular Arabica or Robusta coffee beans. Most decaffeination methods are considered natural as they use only water or naturally occurring chemicals to remove the caffeine. But this still requires processing.

A brief history of decaf coffee

The first commercial decaffeination process began in 1903. Coffee, as a beverage, dates back as far as the 1400s. So it took a while for this process to be imagined and brought to fruition. What may have interested people to remove caffeine from coffee? Who knows! Someone might know but let’s not worry about that. The first decaffeination process used benzene - a chemical solvent that was eventually found to be a bit nasty, so we don’t use it anymore. Instead, we use other perfectly safe solvents–including water!

Fast forward 100 years to today, and we can find great decaf at specialty shops all around the world (the greatest ones are at Abyss).

But how is the caffeine removed? Let’s take a look at the three most-popular decaffeination methods, which you’ve most likely heard of.

Decaffeination methods

A bag of decaf might give you a hint about the decaffeination method that was used to remove the caffeine from the green beans, although it can also be hidden if you don’t know what to look for. These are the terms to know – if you see one of these names, you will be able to tell how the caffeine was removed.

Note: All decaffeination methods apply to green coffee beans. In other words, coffee is decaffeinated after it is processed (washed and dried), but before it’s roasted! Specialty decaf coffee is usually roasted at your local roastery just like regular specialty coffee. 

1. Sugarcane or ethyl acetate (EA) decaffeination

Ethyl acetate (or EA) is a chemical that occurs naturally in many fruits, and is produced as a byproduct during the fermentation of sugarcane to produce refined sugar. So, for the so-called sugarcane decaf process, naturally derived ethyl acetate is used to bind caffeine and remove it from the coffee.

In this process, green coffee beans are first steam-heated, which serves to open up the microscopic pores in the beans to allow better access to the caffeine. The beans are then soaked in a solution of ethyl acetate mixed with water, and the caffeine is pulled out of the beans into the liquid solvent by natural diffusion (molecules move from areas of high concentration to areas of low concentration). As the caffeine leaches out of the beans and the solution becomes saturated with caffeine (meaning no more caffeine will dissolve in it, or it begins to slow down), the solvent is removed and replaced with fresh solvent to keep the process moving along naturally. After about 8 hours of this, the coffee beans are >97% caffeine-free. The beans are removed from the solution, steamed once more with water vapour to push out remaining ethyl acetate, and then dried. The caffeine can be recovered from the ethyl acetate solution by evaporating the solvent, and the solvent can also then be recycled back to decaffeinate more coffee, which improves the overall sustainability of the process. Ethyl acetate evaporates at 70 °C, so when coffee is roasted at temperatures much higher than that, any remaining traces are removed from the beans. Even if traces were to remain, ethyl acetate is safe to consume in such small amounts, and has a naturally sweet flavour. This is generally the preferred decaffeination method, as it is thought to best retain the subtle flavours that make specialty coffees from different regions so special.

Cafe Imports have produced a handy diagram illustrating the sugarcane EA decaffeination process. Something that stands out with sugarcane/EA decaffeination is that the process can be done at origin. This means that the producers and/or cooperatives who grow the coffee and process it can also decaffeinate it and sell the decaf green beans. Every step that stays at origin means more value remains with the farmers.

All three of the decaf offerings we have at the moment were decaffeinated using the sugarcane/ethyl acetate method.

2. Swiss Water Process (SWP) decaf

The Swiss Water Process is a widely known decaf method, but sit tight because it’s a complex one to explain. Swiss Water is actually a company, and Swiss Water decaf coffee is processed at their facilities in Canada. The name comes from the fact that the process was originally developed in Switzerland, and only water comes into contact with the coffee. And not just any water. Nowadays, glacial water from the mountains of Western Canada is used to decaffeinate the coffee. Yum.

The quick version is like this:

1. Green Coffee Extract (GCE) is produced by extracting everything from green coffee beans into water, and removing the caffeine. So we have a solution of water filled with compounds in green coffee except for caffeine. Good.
2. The green coffee beans to be decaffeinated are soaked in water to rehydrate them. This also serves to clean the beans from dust/dirt/etc.
3. The GCE is then circulated around the coffee beans for 8 to 10 hours. As we mentioned above, molecules naturally move from areas of high concentration to areas of low concentration. Since the GCE is already ‘full’ of all of the things except caffeine, only the caffeine moves from the coffee beans into the solution. Tricky!
4. As the GCE becomes saturated with caffeine, it’s passed through a proprietary (secret) filter system based on carbon (which is naturally occurring and inert). This keeps the GCE solution low in caffeine so it can continue to extract the caffeine from the green beans. It also means that the GCE can be reused continuously, making the process fairly sustainable.
5. The filter is also reused, by removing it between processes and burning the caffeine out of it! (Carbon isn’t destroyed by reasonable amounts of heat - it vaporises at a cool 3,642 °C)
6. Once the caffeine content of the green beans reaches <0.1% (i.e., 99.9% decaffeination), the beans are removed from the solvent and dried.

You can learn more about the Swiss Water Process directly from Swiss Water’s website.

3. CO₂ or ‘supercritical carbon dioxide’ decaf

We’re getting into big words, but don’t worry. Supercritical refers to a unique state of matter that’s somewhere between liquid and gas, having properties of both. It’s achieved by heating and pressurising a substance to certain points. Supercritical carbon dioxide, or sCO₂, has the unique ability to dissolve caffeine without dissolving other important flavour compounds in the coffee. So, green coffee beans are steamed to open their pores, then swashed around in a mixture of water and supercritical CO₂ (around 65 °C and 300x normal atmospheric pressure), which selectively extracts the caffeine. The beans are removed and dried–voila! At normal temperature and pressure, CO ₂ is a gas, so any remnants just leave the coffee beans. Anyway, it’s entirely natural and inert (we breathe it out), so this is also considered a completely natural process–although lots of specialised equipment is required, the coffee only contacts water and carbon dioxide. The CO₂ solvent can then be reused by removing the caffeine with more water, and the caffeine can also be used as an additive in other products. So this is also relatively sustainable, although lots of energy is required to pressurise the carbon dioxide.

4. Indirect solvent methods

There are other methods but they are less common and similar to the common decaf methods we described above. In the so-called indirect solvent method, green coffee beans are soaked in hot water, which directly extracts the caffeine (like what happens when we brew roasted coffee). But this also extracts many important flavour components. The beans are removed from the water, and then the caffeine is removed from the water using a solvent like ethyl acetate (as in the sugarcane method) or dichloromethane. This caffeine-free water still contains all the important flavour compounds, so the coffee is placed back in the same water to extract more caffeine. The caffeine is again removed, until there is no caffeine left in the solvent. At some point, the water and beans have the same levels of all those other compounds except for caffeine. The beans can then be dried, but they will naturally lose some of the original flavour due to this somewhat intensive processing. This method is not likely to be used for specialty coffee as it risks losing the subtle flavour notes.

Reasons to drink decaf

Coffee is recognized for having a multitude of health benefits, being packed with antioxidants and heart-healthy compounds. Black coffee has no calories, but a lot of flavour. And coffee is a centrepiece of many daily routines, rituals, and gathering. So there are many reasons to drink decaf coffee, which offers all of those benefits, just without the caffeine. Here are the stories of a few hypothetical people, and why and when they choose to enjoy a decaf coffee:

• John is just obsessed with coffee - the flavour, the smell, the feel of the cup in his hands. But he feels it just makes him too energetic in the afternoon, and then he doesn’t feel like sleeping but he has to wake up early to work at 7 am. So after he finishes at work at 3 pm, he switches to decaf for the rest of the day. He can enjoy a coffee after dinner and even in bed, and has no trouble sleeping.
• Sandra learned at a young age that she’s sensitive to caffeine. It makes her anxious and uncomfortable, but she actually works in a coffee shop and loves drinking coffee. So she only drinks decaf. She can share in the ritual and the joy with everyone, but doesn’t get anxious.
• Enrique’s favourite coffee he ever tasted was decaf, and now he’s convinced that decaf is just better in general. He’s probably created an illusion for himself, but it doesn’t matter. He loves decaf coffee and he drinks it–all day, every day.
• Liliana always drank coffee, but recently started taking a pre-workout supplement that’s packed full of caffeine. So she switched to decaf because the combination was just too much.
• Jimena became pregnant a few weeks ago, and although she understands that caffeine is generally safe for pregnant women, she just decided to switch to decaf for the time being.
• Gerald was a smoker all his life, and typically drank 5 coffees per day. He quit smoking 6 months ago, and suddenly felt way too stimulated all the time. He did a bit of research and found out that his body used to metabolise caffeine faster due to the presence of nicotine. So he changed his habit and makes 3 of those 5 coffees decaf, and he feels great.

In the end, the reason why doesn’t really matter - if you want to drink decaf, go for it! Decaf used to be thought of as somewhat of a sacrifice (or even a sacrilege), since the quality of decaf just wasn’t all that great in the past (“why take amazing coffee and do all these weird things to it?”). But that’s no longer true. Decaf specialty coffees can be just as excellent as their caffeinated counterparts – if you don’t believe us, try one of our special decaf offerings from Colombia.

Does decaf mean zero caffeine?

Decaf does not have zero caffeine. It generally has a bit.
In the US, 97% of caffeine must be removed, so an average cup could have up to 3–7 mg of caffeine. That’s not enough for most people to feel any effect, but it could be enough to bother someone with extreme sensitivity or an actual allergy to caffeine.
In the EU, the regulation is stricter, and only 0.1% of the caffeine should remain. That’s still not caffeine-free, but there are really only minor traces present.

And that’s about it. If you have any questions, feel free to write to us or stop by the cafe. And if you want to do some hands-on investigation for yourself, buy a bag and play around with swapping one or two of your daily coffees for decaf. See how it feels for you!