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What Is "Flowering" in Coffee?

Do you find it difficult to make delicious coffee at home like in coffee shops? You may think you've got it all figured out, ticking every box, and getting yourself the best equipment you can afford, but you need to take a look at your coffee brewing technique.

Coffee bloom is a crucial variable that is overlooked by most home coffee enthusiasts in the early learning stages.

However, this process should not be overlooked. When you understand the benefits of blooming in coffee, you will bring your once dull and sour brew to life and transform it into the perfect cup that will impress almost any coffee lover.

What is Coffee Bloom?

You've probably heard baristas in coffee shops talk about "blooming" when talking to their colleagues behind the counter, and you were probably momentarily confused.

After all, it's a strange term to use when brewing coffee, and something you'd expect to hear in a flower shop rather than a coffee shop!

What is a coffee flower? You've probably seen this reaction before when your coffee grounds start to swell and foam, but you haven't explained that there is a name or a reason behind it.

Coffee blast is a natural part of any brewing process, and the "bloom" begins when the hot water hits the ground causing an instant release of gases.

When you add a small amount of water to the coffee grounds, the CO2 is expelled from the cells of the coffee; The fresher your coffee, the bigger the bloom!

It typically takes 30 seconds for the coffee to rise and you will see your coffee grounds begin to rise and form into a dome-like shape; At this stage, you can continue your pouring process.

In simple terms. The coffee blast allows the hot water to replace most of the CO2, essentially preparing the coffee bed for proper extraction.

If you don't see a coffee flower, it most likely means your coffee is not fresh. Most of the degassing (CO2 release) has already taken place, and unfortunately, many of the flavor compounds locked inside the beans will also be spoiled.

So blooming coffee is a good thing to do and tells you a lot about the quality of the coffee beans.

The key to a great coffee experience paired with a rich and flavorful brew is to keep the freshly roasted coffee whole for as long as possible.

This means only buy whole roasted coffee beans and grind them just before you need them, ideally within a week of the roast date.

After the coffee is ground, there is more surface area. This will cause the gas to be released faster; The coffee no longer has a protective shell that keeps the gas inside.

The science behind coffee's bloom is fascinating, and understanding how carbon dioxide interacts with your coffee is something worth learning.

- Let's take a closer look.

Carbon dioxide has a sour taste. So, when your coffee isn't blooming due to stale coffee or you haven't allowed enough time for the blooms to be gassed, the CO2 will brew your coffee and give it a sour taste.

Carbon dioxide also repels water, which is not a good thing when you try to soak your ground coffee and causes extraction.

It's water that extracts flavors from coffee, so if the carbon dioxide doesn't have a chance to dissipate, the water won't fully interact with the coffee.

But remember, carbon dioxide has a sour taste. So if you haven't opened your coffee, you will have a sour taste and limited extraction that equates to bad coffee taste.

Factors Affecting How Coffee Blooms

Blooming coffee isn't always a given. As I mentioned earlier, the freshness of your whole grain coffee is a very important variable, but many other factors can affect flowering.

The following are known to affect the rate at which gas is lost from coffee beans as soon as they complete the roasting process.

Coffee Bean Origin

The origin of the coffee bean can affect the flowering time of the coffee. Some regions produce coffee that will be degassed faster than other coffees grown in other regions.

coffee roasting level

Different coffee roasts will have different blooms. For example, darker Italian roasts typically contain less gas compared to lighter roasts.

Temperature and Storage

Proper storage of coffee is vital not only for impressive blooms, but also for the overall freshness of your coffee.

Storing the coffee in a warm environment will allow the gas to come out faster. We recommend storing your beans in an opaque container in a cool pantry or back of the cupboard.


Humidity and proper storage go hand in hand.

If you invest in a good coffee can and keep your coffee away from anything that produces heat in your kitchen, like a kettle or stove, you don't have to worry.

grinding size

And finally, the size of your ground coffee.

Even something as simple as how finely you grind your coffee, how quickly will it release carbon dioxide?affects it.

Fine grinds will release gas from the surface area much faster than coarse ground coffee, as there is more surface area for the carbon dioxide molecules to condense and stabilize.

To bloom or not to bloom?

If you've come this far, I'm sure you already know the benefits of blooming your coffee.

The brewing method is quite simple and involves adding just enough water to moisten your freshly ground coffee (rule of thumb: learn more about the ratios of 1 gram to coffee per 2 grams of water).

Depending on your coffee machine, the brewing process will be slightly different.

So keep reading, we'll briefly cover how to make coffee bloom in a French Press, pour over it like Chemex and Automatic Drip Coffee Makers.

How Coffee Blooms

The flowering process differs slightly depending on the type of coffee brewing method you use.

Let's take a look at three familiar coffee machines.

Pour Too Much

For spilled coffee in coffee machines like the Hario V60 or Chemex, pour the hot water slowly in a circular motion, starting from the outer edge, being careful not to hit the paper filter, and working your way slowly towards the centre.

The trick is to use just enough water to keep the coffee grounds saturated and evenly wet, but not too wet so the coffee starts dripping from the filter.

Let the coffee bloom for about 60 seconds. Once blooming is over, continue to slow down the spill using your gooseneck kettle and the regular "pour-on-top" technique.

French Press

The flowering process for the French Press is very similar.

After adding your coarsely ground coffee to the French Press, slowly pour a small amount of hot water over the grounds.

You need to add just enough water to moisten the coffee - aim for the consistency of wet sand, or about 2 parts water to 1 part coffee.

If your coffee is fresh, you will immediately begin to see the coffee grounds bloom.

Let the process take about 20 seconds and gently soften and stir the ground to make sure it all comes into contact with the water.

When you're satisfied, complete your regular French Press brewing regimen.

Automatic Drip Coffee Machines

Yes, it is also possible to flower the coffee using an automatic drip coffee maker with a button.

Place your paper filter in the drip basket (better results using a Gold Filter like this one) and add your ground coffee.

Slowly pour in enough water to wet the soil, but never so much that it penetrates completely and drips from the filter into the pitcher.

Let the coffee bloom for about 60 seconds and continue your normal brewing cycle in your machine.

When you leave the coffee to open in an automatic dripping brew machine, you can definitely taste the difference compared to not opening it.

Pre-brewing the water will create an even pool on the coffee grounds instead of a few drip troughs created by the machine.

This even pool of water will allow for a more even extraction and ultimately a tastier cup.


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