You've quite likely seen memes with the "Death before Decaf" slogan. The mere mention of decaf has for a long time been considered sacrilege, with trending instagram hashtags like #caffeineaddict, #fueledbycaffeine, #mondaymood and my personal favourite #deathbeforedecaf. But the reality is that decaffeinated coffee has come a long way over the years, and you no longer need to sacrifice quality in a cup of decaf. In fact, worldwide trends have shown an increase in the consumption of decaffeinated coffee, and the specialty coffee culture has embraced this, with some very rare decaffeinated coffees becoming available.
So if you've ever spurned the after-dinner coffee laced dessert, or avoided the late night coffee culture for fear of staying awake through the night, then this article is for you. We're here to shed some light into how decaf is produced, and debunk some of the most popular myths surrounding decaf.
A typical 250ml cup of coffee contains between 60 to 100 milligrams of caffeine. This may vary considerably though depending on the brewing methods or the type of beans. Robusta, for instance has nearly twice as much caffeine as Arabica. Decaf refers to coffee made from beans that have had at least 97% of their caffeine removed prior to roasting.
How exactly do we remove the caffeine?
The first commercial process for decaffeinating coffee was invented by a German merchant named Ludwig Roselius in 1905. This process used benzene as a solvent to remove caffeine. However, benzene is not used any longer as a solvent. Modern solvents are much more gentle, and are often referred to as "natural" solvents, due to the fact that they do occur naturally in small quantities in ripening fruit.
But not all decaffeination processes use solvents. Modern decaffeination processes can be grouped into two main categories: solvent based processes and non-solvent based processes.
Solvent based processes
Solvent based processes involve using a chemical solvent to remove the caffeine from the beans. The beans may be soaked in the solvent directly, to remove the caffeine. The caffeine laden solvent is drained away, and the beans steamed to remove any residual chemical solvent. This is called the direct method.
Alternatively, the beans may be soaked in water, which absorbs the caffeine and other coffee flavour compounds. This water is then transferred to a separate tank and treated with solvent to remove the caffeine. The caffeine laden solvent is then evaporated. Finally the flavour containing water is reintroduced to the beans to absorb the coffee oils and flavours. This is known as the indirect method, as the beans never actually come into contact with the chemical solvent.
Solvent based processes are often also called "The Natural Decaffeination Method" due to the solvent being used. Usually, when a method is not specified for decaffeination, a solvent based method has been used.
Non-solvent based processes
As alternatives to the chemical solvent processes above, there are two non-solvent based processes: The Swiss Water Process; and The CO2 process.
The Swiss Water Process is a chemical free process, relying on water solubility and osmosis to remove caffeine. Green coffee extract is obtained by first soaking green coffee beans in water to dissolve the caffeine and other flavour compounds. This solution is passed through an activated charcoal filter removing the caffeine molecules from the solution, resulting in a batch of caffeine and flavour free beans in one tank, and a batch of caffeine free and flavour containing liquid in another tank. We're now ready for the truly ingenious part of this process. The flavourless, caffeine free beans are discarded, and the water with the concentrated green coffee extract is retained to soak a new batch of beans. Since this water is saturated with the flavour compounds, but contains no caffeine, it absorbs just the caffeine from the the beans without extracting any of the flavour compounds. The process is repeated several times until the targeted caffeine content is reached.
The CO2 process is the most recent process developed to remove caffeine from coffee. It uses liquid CO2 instead of organic chemical solvents. The green coffee beans are soaked in water. Liquid CO2 is then forced into the coffee at high pressure. The liquid CO2 dissolves and extracts the caffeine, leaving behind the other flavour compound in the bean. This liquid CO2 with the dissolved caffeine is transferred out into a separate tank. The pressure is released and the CO2 returns to its gaseous state releasing the dissolved caffeine molecules. The CO2 is reused, making this a very commercially viable process.
The majority of the world's commercial coffee is decaffeinated using the CO2 process.
Debunking some decaf myths?
Myth 1: Decaf tastes bad
In fact caffeine is a bitter compound. Decaffeinating coffee makes it slightly sweeter highlighting the acidity and fruity notes in the coffee. Often that change is only really discernible by people with a highly trained coffee palate. Baristas strive for flavour in their cup, without the bitterness. So as long as you brew with the focus being on the flavour rather than the caffeine content, you're going to get a great cup of coffee. Having said that, remember that you do need to start with good beans that have been carefully roasted to bring out the best flavour profile that the beans have to offer.
The flavour of decaf really depends on the quality of beans and the skill of the roaster, rather than the caffeine.
Myth 2: Caffeine levels in decaf vary wildly
While it is true that there is a minute amount of residual caffeine remaining in decaf, the decaffeination process removes a between 97% to 99.9% of the caffeine from the beans. This number is carefully controlled during the decaffeination process, and very repeatable, resulting in a highly predictable and consistent outcome.
Caffeine levels are minute, and highly controlled to ensure that decaf meets the US FDA acceptable standard of having at least 97% of the original caffeine content removed.
Myth 3: Decaf contains carcinogenic chemicals
Not all decafs are processed the same way. It's important to know what process your coffee went though. While the solvent based processes use organic chemicals described above, the BMJ (British Medical Journal) has published a study showing that decaffeinated coffee does not appear to have any adverse health effects.
Decaf beans processed using either the indirect or non-solvent based methods are not exposed to any organic solvents.
Myth 4: I don't have choices when it comes to decaf
Many roasters usually only stock one choice of decaf beans, but as the popularity of decaf grows, you should start seeing a variety of decaf beans becoming available at your favourite roastery. Baristas are even starting to compete with rare and specialty decaf coffees in competitions.
So while choices are relatively limited for now, you should start seeing this change in the future.
So where do we get our hands on great decaf?
We've been working behind the scenes to get our decaf to the high standard you're accustomed to from all of our coffees. We're almost there... We've selected a Colombian Excelso bean that has been decaffeinated using the CO2 process, and our new decaf should be ready for you early in September, just in time to welcome Spring.
Leave us a comment below before 31 August 2020, and stand a chance to get one of the first bags of our brand new decaf.