What is Coffee Degassing?

During and after roasting, many processes and chemical reactions take place within the cellular structure of the coffee beans.

One of these is known as degassing. But what is coffee degassing? Let’s take a look, shall we?

What is coffee degassing?

Coffee degassing is the natural release of gases from roasted coffee. We say ‘gases’, but it’s mainly carbon dioxide we’re talking about here.

Gases form inside coffee beans when we roast them. The high temperatures of the roaster cause the complex carbohydrates inside the raw beans to break down and change the coffee from grassy-tasting green beans to delicious, full-flavoured roasted coffee. This clever process also creates water vapour and… carbon dioxide!

You might have heard of the ‘first crack’ in the roasting process. This is when coffee turns into popcorn! Jokes.

Well, not really, because the roasting beans do start to pop like popcorn. This sound tells us that the beans are beginning to emit (rather than take in) heat and release carbon dioxide. The release of CO2 continues after the roast – this is coffee degassing!

The gases that form during roasting will naturally escape in the first few days after roasting. Drinking coffee within its first few days? During that time, you may notice small bubbles form in your coffee. These bubbles are nothing to worry about. Too much carbon dioxide left within the coffee, however, can result in an uneven extraction and can, therefore, cause flavours and aromas to become bland. To avoid this, here at Two Chimps Coffee we inform you of the roast date on every bag so you can see when your coffee was freshly roasted and therefore plan accordingly.

Why does coffee degassing matter?

For truly show-stopping coffee, it’s best not to brew with “gassy” beans. If you brew with coffee beans before they’ve degassed then the release of carbon dioxide will take place there and then as you make your coffee.

Even, smooth and harmonious… these are all words we like when it comes to coffee. The problem is that yet-to-degas coffee causes an uneven extraction. Why? It’s down to those small CO2 bubbles the degassing coffee is still releasing. These gassy pockets disrupt the extraction and have a negative impact on flavour.

And that, folks, is why coffee degassing matters!

So, how long does it take to degas coffee?

Now we know what coffee degassing is, we need to know how long it takes.

If you’re worrying that you’ve got to wait weeks for your coffee to degas, you’re in for a nice treat. Because coffee degassing takes just a few days!

If that, to be honest: the roasted beans lose around half of their carbon dioxide within the first 24 hours after the roast. In general, coffee degassing takes between one and four days. Phew.

Darker roasts get their skates on with degassing, too. They degas a little faster than light roasts because they spent more time in the roaster. More tiny cracks have had the chance to form in the bean, which makes the carbon dioxide release a little faster.

Lots of other factors affect how long it takes a coffee to degas:

• Bean size
• Coffee processing method
• The speed of the roast

But, in general, most coffees take just a few days to degas.

Does the brewing method make a difference?

Different brew methods like different amounts of coffee degassing. This is some advanced coffee science, but we’ll take a look because it’s pretty fascinating!

The bit we’re interested in here is the time the coffee and water are in contact. Cafetieres and pour over devices leave the ground coffee and water steeping together for longer than espressos, which means they suit coffees that aren’t as degassed.

Espresso machines, on the other hand, need well-gassed coffee beans.

The brew time for an espresso is very short, which means those itsy CO2 bubbles have a bigger effect on the extraction. The shot might take longer to pull as the bubbles obstruct water flow. The flavour might not quite as good, either.

If you’re making espressos, it’s great to leave your coffee degassing for five to seven days after we roast it. But we’re getting right into the nitty-gritty of coffee brewing here. Don’t worry if you use your beans straight away – the coffee will still taste awesome!

How to speed up the degassing process

Grinding coffee beans makes coffee degas faster because finer grounds allow more CO2 to be released.

HOWEVER! Don’t grind too soon. When we brew, we need some carbon dioxide to stop the final coffee tasting flat and dull. Grinding too soon before brewing can lead to stale coffee, too. Sad face.

Ordering ground coffee from Two Chimps? Great move. We grind your coffee on the day of dispatch to ensure it reaches you at optimum freshness!

Do I need to let my Two Chimps Coffee degas then?

Nope, is the short answer. We see to it for you!

We roast our coffees in small batches several times each week. Then, we leave your perfectly roasted beans to rest for a day or two before posting. These couple of days, teamed with the short time your coffee spends in First Class delivery, give the coffee the perfect amount of time to degas. Clockwork, if we do say so ourselves.

What’s more, we send your coffees out in clever coffee pouches. These recyclable bags feature nifty valves that allow carbon dioxide to escape. This means that fresh-as-fresh, ready-to-brew coffee pops on your doormat! You can even poor them into your stylish little Two Chimps tins if you like!