What Is Coffee Bloom And Science Behind It

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Coffee Bloom Guide

Rumor has it that one day in 700 AD, Kaldi, an Ethiopian goat herder spotted a few of his flock acting a ‘wee bit strange’. And by a ‘wee bit’, I mean they looked like they were dancing. The cause of this behavior was discovered to be these vividly colorful looking berries. The rest as they say, ‘Is history’.

Since its introduction to domestic life, coffee has continued to evolve through time and across geographical borders. The proof of this lies in the fact that the streets are filled with cafes around every corner.  You can’t walk more than a hundred meters in any direction without spotting a new ‘hot spot’ that boasts of getting you something from the caffeine world that you’ve apparently been desperately missing out on.

Coffee drinkers vary on a wide spectrum. Some can be classified into those that prefer to be involved in the coffee-making process, and those who’d rather have a machine do all the work.

While some have chosen to experiment with the exact method that goes into making that perfect cup, others have been brave with the ingredients. If you are someone who absolutely adores coffee and will like to save those grands; you have no doubt tried your hands in your kitchen’s coffee corner. Making the perfect cup of coffee you will find, is an amalgamation of art and science. And the sweet spot achieved in this mélange of artistic skills and science is ‘Coffee Bloom’.

What is Coffee Bloom?

Coffee Bloom

If you’re someone who delegates the coffee-making process, you’ve probably never heard of a coffee bloom in your entire life.

If however, you like to have your hand in, coffee blooming could be something you’ve probably seen a million times but had never put a word to the phenomenon.

Before you ask: ‘No. There aren’t any flowers involved in the process’.

In the simplest terms, the coffee bloom is the foaming and bubbling you see when you pour some boiling water over freshly ground coffee beans. While the effect of a good bloom is most noticeable if you are someone who likes their coffee black, it can also help infuse more flavor if you prefer your daily beverage with cream and sugar added in. Though the most obvious benefit of blooming is visible in the pour-over or french press method. It is never a bad option to bloom before brewing if your coffee preparation technique allows for it. 

What does Coffee Roasting have to do with Bloom?

You might have noticed the term roast on the label of your coffee purchase in the supermarket. Traditionally, you get to pick between light roast, medium, medium-dark, dark, and for the truly adventurous, double roast.

This is because before being neatly packaged into the coffee that sits on your kitchen counter, coffee beans are roasted to pull flavor and that delicious aroma into the bean. During this process, the beans trap carbon dioxide within them. This gas is gradually released into the air roughly over the course of 14 days through a process known as degassing.

Coffee Roasting

Morning Coffee Experiments

So if you’re wondering why your morning coffee look like a chemical experiment with all the bubbling and oozing, here is your answer to ‘Why does coffee bloom?

As soon as the steaming water hits the coffee grinds, what you see is the release of all that carbon dioxide that had collected in the beans during the roasting process. If you’re using your favorite pour-over drip cone, your eye will catch the coffee grounds swelling/ foaming up. Essentially, they will bubble or puff up until they come to settle. A French press will present a different performance wherein the grounds will form a foamy raft right on top of the hot water, and float there buoyed by the gas. All this, until you show stir your spoon like a wand: stir them back down to settle.

The whole spectacle lasts for anything between 30 to 90 seconds. Once the process has finished, you can go on with the remaining steps in your coffee brewing process.

Why do we do it?

You might be wondering the point of it all. While we cannot deny coffee blooming is a spectacle for the eyes, there are other reasons to consider. Simply put, releasing the carbon dioxide trapped within the beans improves the flavor of your daily beverage.

If you’ve ever found your coffee tastes a little sour, acidic, or flat, a lack of a proper bloom would be the reason why. Carbon dioxide if left within the beans, is sour to taste which ends up affecting the taste of your daily drink and could turn your day sour too.

If the carbon dioxide is not allowed to fully escape the beans during the brewing process, it prevents the water from bringing out the aroma and flavor from the beans into your beverage thus denying you complete satisfaction.

Things that Impact Coffee Bloom

1. Freshness of the Bean

Once the coffee beans are roasted, the carbon dioxide locked within them seeps out little by little day by day. It is a very safe bet to say the fresher your coffee beans, the more magnificent the coffee blooms.

The timing of grinding the coffee also places a very important role in releasing the carbon dioxide within the beans. If you’re looking for good bloom, try to grind the beans as close as possible to consuming the beverage.

2. Packaging and Storage

Before consumption, the environment and temperature in the place your coffee get stored plays a very big role in the quality of bloom. High temperature increases the rate at which the carbon dioxide is expelled from the beans. If your coffee was stored somewhere warm, chances are that quite a lot of the gas in the beans has already gotten out and you should prepare for a less impressive bloom. You need to also take humidity levels into account. While dryer environments help more gas escape from the bean, an extremely humid setting could cause mold or fungus to set in.

3. Hardness of the Bean and Roast Level

The density of the bean also plays a role in the quality and quantity of the bloom. The harder the bean is to touch, the slower the release of gas. Similarly the higher the intensity of your roast on the coffee bean, the longer it will take for the gas to escape from the bean.

Which in turn means it would give you a more spectacular bloom!

4. Where the Bean Hail from

While this is something we might have the least control over. It is a fact that a certain variety of beans ‘degas’ slower than others depending on origin region.

How to Treat Yourself to the Perfect Bloom

For those amongst you that enjoy a pour-over cup of coffee, treating yourself to the perfect bloom almost feels like a performance at the theater. Here is how to get it right:

Perfect Bloom by Pour Over

What you need

  • Hot water – If you want to be very precise, it is suggested the water should be between 92 to 96 degrees Celsius
  • Freshly ground coffee
  • A container to bloom
  • Paper/reusable filter

The steps to follow:

  1. Place your ground coffee beans in your paper/ reusable filter over a container of your choice and convenience.
  2. Pour in the steaming water and wait. P.S: The ratio of coffee-to-water should roughly be double. That means if you’ve got 30 gm of coffee in your filter you should pour in 60-70 gms of water.
  3. You will be treated to a visual of the coffee grinds bubbling over. Wait for one to two minutes. If you can’t see anything happen at all, chances are the beans have already degassed. That could mean your coffee is either stale or was not stored correctly.
  4. Add some more water to check if there is still more gas in the beans that need to escape which might happen if your coffee is really fresh.
  5. If everything remains unchanged, continue the remaining steps of your standard brewing process.

Coffee Blooming Hacks – Tips and Tricks

  • When pouring water over the ground beans, it’s important to go slow.
  • Try and move the water in a circular motion starting from the out and working your way inwards.
  • When coffee blooms, the grinds will double, possibly triple in quantity. Make sure you have adequate room for the expansion so as to not have a mess on your countertop.
  • If you want to be extra cautious while you pour, consider getting yourself a good kettle for coffee.

Make or Break your day with Perfect Bloom Coffee!

While fretting so much over your daily cup, it might seem extreme to some. For others, it is not too much of an exaggeration to say a well-made mug of coffee can make or break a day. You might be shocked or pleasantly surprised to know the downright bizarre ingredients that some people include in their morning brew. From butter, salt, raw eggs, or a dash of whisky to experiment. People are willing to pull a few tricks to make their beverage a little extra special.

Coffee bloom happens to use science to provide a treat for all your senses. While we may never know for sure what Kaldi thought when he saw his goats dancing after discovering coffee, one thing is for sure. No one ever thought that this tiny little bean would have the world revolving around it!