Harry poseeraa Kirjalan kahvilan pöydällä jalka ilmassa ja kahvikuppi kädessä, edessään kofeiinittomat Sariola-kahvipaketit

Decaf coffee: how is caffeine removed and what does it taste like?

Decaffeinated coffee, or decaf, is coffee that has had almost all of its caffeine removed before roasting. In this guide we explain how caffeine is removed from coffee, how much caffeine is left in decaf, what good decaf tastes like and how to brew it at home. So if you're wondering which decaf coffee is best for you, you're in the right place.

Decaf is a bit like alcohol-free beer: lots of people are sceptical until they taste a good one. Our crew is firmly on team decaf, and so are our customers. One of them wrote this about our decaf Sariola: “This coffee doesn't give up anything for being decaf. If you like quality light roast coffees, you can order this on that basis alone, and being decaf is a nice bonus on top.”

What is decaf coffee?

Decaf is regular coffee where the caffeine has been removed from the green coffee, that is the unroasted beans, before roasting. So the roaster receives green beans that are already decaffeinated and roasts them in much the same way as other coffees. The English name decaf comes from the word decaffeinated.

Not all the caffeine can be removed, but almost all of it can. EU Directive 1999/4/EC allows coffee extracts sold as decaffeinated, such as instant coffee, to contain at most 0.3% caffeine in the dry matter. There's no common EU limit for roasted coffee, but some countries have set one nationally. Under the German coffee regulation, for example, decaffeinated roasted coffee may contain at most one gram of caffeine per kilo of dry matter, or 0.1%.

The history of decaf starts in Germany. In 1905 Ludwig Roselius patented a method that removed caffeine using benzene, and the following year he founded the Kaffee HAG company. Thankfully benzene was abandoned long ago, and today caffeine is removed with water, carbon dioxide or solvents approved for food use.

How is caffeine removed from coffee?

The methods usually start the same way: the green coffee beans are moistened with water or steam so they swell and the caffeine can move. Then the caffeine is bound to a solvent, water or carbon dioxide, and finally the beans are dried. There are three main methods.

Solvent methods: dichloromethane and ethyl acetate

In the solvent method, steamed beans are treated with a solvent that binds the caffeine, and finally the beans are steamed again to remove solvent residues. The most common solvents are dichloromethane and ethyl acetate, or EA. Under the EU extraction solvents directive, roasted coffee may contain at most 2 mg of dichloromethane residue per kilo, and ethyl acetate may be used in line with good manufacturing practice.

Ethyl acetate forms naturally during fermentation, and it's found in fruit, for example. In Colombia ethyl acetate is also made from local sugar cane, which is why the method is sometimes called the sugar cane method.

Water method, or Swiss Water

The water method uses no solvents. In the Swiss Water method developed in Switzerland, the beans are soaked in a green coffee extract that has had its caffeine filtered out with carbon filters. Because the extract already contains coffee's other soluble compounds, mainly caffeine moves from the beans into the extract. According to the producer, the process takes about 8 to 10 hours and removes 99.9% of the caffeine.

Carbon dioxide method

The carbon dioxide method was developed by chemist Kurt Zosel at the Max Planck Institute for Coal Research in Germany. In 1967 he noticed that caffeine dissolves in supercritical carbon dioxide, and he applied for a patent on the method in 1970. Carbon dioxide becomes supercritical when the temperature is over 31 degrees and the pressure over 73.8 bar. The caffeine moves from the moistened beans into the carbon dioxide, and activated carbon binds it.

How is the caffeine removed from Sariola?

The caffeine in our decaf Sariola is removed using the EA method. The green beans are sorted and steamed for about 30 minutes at low pressure, which opens up the pores of the bean. Then the beans are placed in a solution of water and ethyl acetate. The tank is emptied and refilled over eight hours until no more caffeine can be detected. Finally the beans are dried and packed for shipping.

How much caffeine is in decaf coffee?

According to the European Food Safety Authority EFSA, a 200 ml cup of filter coffee contains about 90 mg of caffeine and a 60 ml espresso about 80 mg. EUFIC, which shares food information in Europe, says with reference to EFSA's figures that a 200 ml cup of decaf contains about 4 mg of caffeine.

You can also work out the upper limit yourself. We recommend about 60 grams of coffee per litre of water for filter coffee, so for a 200 ml cup you need about 12 grams of coffee. If the coffee contains at most 0.1% caffeine, the cup contains at most about 12 mg, even if all the caffeine dissolved into the cup. So a regular cup contains many times more caffeine.

Does decaf taste the same as regular coffee?

Good decaf tastes like coffee. The flavour comes from the same things as in other coffees: the quality of the green coffee, the decaffeination method, the roast and freshness. Decaffeination can soften some flavours, but decaf made from quality green coffee and carefully roasted is a full-flavoured cup.

Our customers describe dark Sariola like this: “With the right extraction the flavours are clear and smooth. An unusually good dark decaf on the Finnish market.” Light Sariola has been praised for its freshness: “It's fresh, with just the right amount of body, but not too much, so all the brighter flavours come through.”

Why is decaf tricky for a roaster?

Decaffeination changes the structure of the bean. Decaf green coffee is already darker than regular green coffee, and its cell structure is more porous and less dense. That's why it can heat up faster in the roaster and darken quickly, and the colour doesn't indicate the roast level as reliably. The first crack is also often quieter. Decaf demands a sharp ear and eye from the roaster.

Light or dark: which decaf suits you?

We have two decaf coffees, and both are the same Colombian Sariola from the Huila region. Olli roasts it in Mikkeli in two ways:

  • Sariola light is a smooth and sweet decaf light roast: nougat, toffee, wild strawberry and nectarine. At its best as filter coffee.
  • Sariola dark is a full-bodied and chocolatey decaf dark roast: chocolate and dark grape. Suits filter, espresso and milk coffees.

You can get both as whole beans or ground for boiled coffee, Chemex, filter, moka pot or espresso. Compare them side by side on the decaf coffees page.

Product spotlight

A 250 g bag of Sariola costs €9.90 as a light roast and €10.90 as a dark roast. The best price per kilo is in the 1 kg bag: light €37.60 and dark €41.60. We ship orders over €59 free within Finland.

How to brew decaf at home

Decaf is brewed exactly the same way as regular coffee. For filter coffee, about 60 grams of coffee per litre of water works well, and you'll find more tips in our guide How can I make better coffee at home. Choose the grind to match your brewer, or order whole beans and grind just before brewing, because whole beans keep their flavour longer than pre-ground coffee.

For decaf espresso and milk coffees we recommend dark Sariola. Light Sariola is at its best as filter coffee or pour over. And yes, you're allowed to drink decaf in the morning too. We won't tell anyone.

Try decaf Sariola at home or drop by our café on Nuijamiestenkatu in Mikkeli.

Decaf coffee in brief

  • What it is: coffee with the caffeine removed from the green beans before roasting
  • Caffeine left: about 4 mg in a 200 ml cup, compared to about 90 mg in filter coffee
  • Methods: solvent methods (dichloromethane and ethyl acetate), the water method (Swiss Water) and the carbon dioxide method
  • Taste: good decaf tastes like coffee when the green coffee is high quality and the coffee is freshly roasted
  • Kirjala's decaf: Sariola, Colombian arabica, decaffeinated with the EA method, light and dark roast, 250 g from €9.90

Frequently asked questions about decaf coffee

Is decaf completely caffeine-free?

Not quite. Almost all the caffeine has been removed from decaf, but a small amount always remains. According to EUFIC, a 200 ml cup of decaf contains about 4 mg of caffeine (based on EFSA data), compared to about 90 mg in a regular cup of filter coffee. The amount varies depending on the coffee, the serving and the decaffeination method.

How is caffeine removed from coffee?

Caffeine is removed from the green coffee beans before roasting. The beans are moistened with water or steam, and the caffeine is bound to a solvent such as ethyl acetate, a green coffee extract or supercritical carbon dioxide. Finally the beans are dried. The caffeine in Kirjala's Sariola is removed with the EA method, using ethyl acetate. Other common methods are the water method, or Swiss Water, and the carbon dioxide method.

Is there any solvent left in decaf?

The EU regulates the solvents used in decaffeination. Under the extraction solvents directive, roasted coffee may contain at most 2 mg of dichloromethane residue per kilo, and ethyl acetate may be used in line with good manufacturing practice. The beans are steamed after treatment. The water method uses no solvents, and in the carbon dioxide method the solvent is carbon dioxide. Ethyl acetate also forms naturally during fermentation, and it's found in fruit, for example.

What's the best decaf coffee?

The best decaf is fresh, made from quality beans and suits the way you brew. If you love bright and sweet coffee, try Sariola light. If you drink full-bodied and chocolatey coffee, go for Sariola dark. Our customers have given light Sariola 5.0 and dark Sariola 4.8 stars out of five. Read the reviews on the product pages and choose the roast to suit your taste.

Does decaf work for espresso?

Yes. Decaf is extracted in an espresso machine the same way as regular coffee. For decaf espresso and milk coffees we recommend dark Sariola, whose full-bodied and chocolatey flavour also suits cappuccinos and lattes. Choose Espresso as the grind, or order whole beans and grind them yourself. Both Sariolas are also available espresso ground. At our café we often use a blend of the two coffees mentioned above.

Sources

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