You hear bloom and your first thought is a bouquet of beautiful flowers. That’s not what we’re talking about when we refer to coffee bloom! The blooming of coffee helps to identify that the beans and grounds are fresh and gives them a chance to release some Carbon Dioxide which could otherwise produce a slightly sour taste!
Perfectly brewed coffee can be a wonderful thing. The world of coffee brewing can be complex, with varying methods that mainly depend on one’s personal taste. The good news for a coffeeholic is that it is possible to brew the perfect cup o’ Joe in the comfort of your home that rivals that of large coffee establishments.
But, crafting that perfect cup of coffee (Best Coffee Cup Material: Ceramic vs Glass vs Steel vs Plastic) is both an art and a science, as in, the well-balanced, nuanced taste is only possible if you keep an eye on the various factors that go into the brewing process. This also includes something known as “bloom.”
If you have friends who love coffee or brewing coffee (Can You Freeze Brewed Coffee?), the chances are that you’ve come across the word “bloom” before. For those who associate the word with flowers, it can be confusing to understand. Here, we are going to take a look at exactly what the word “bloom” means in the context of your favorite black liquid – coffee.
What is Coffee Bloom?
When you initially pour water over coffee, you might not notice the coffee grounds (Can You Reuse Coffee Grounds Twice?) rising up and out the filter, but you will notice the bubbly foam that rises above the coffee while the hot water is being poured into the filter bed.
The coffee blooming mainly depends on the size and consistency of the coffee grounds, which also needs to be factored in. When coffee is finely ground (What Is the Difference between Instant and Ground Coffee?), you get more surface area. This increase in the surface area results in more water reaching and reacting with the coffee at a much faster rate. As a result, more CO2 is released when the water comes in contact with the coffee grounds, which results in blooming coffee.
What Causes the Bloom when Brewing Coffee?
So, the answer here is, what causes the coffee to bloom? The coffee blooming gives crucial information on the type and quality of the coffee being brewed. Pour-over coffee bloom is the quick bubbling up of the carbon dioxide and coffee grounds that takes place while brewing freshly roasted coffee – How to Brew Low Acid Coffee for Upset Stomachs.
This bubbling of carbon dioxide gas occurs during the initial brewing stage, with the hot water accelerating the release of carbon dioxide when it comes in contact with the fresh roasted coffee (Can You Roast Coffee At Home?). In short, the coffee blooming is the accelerated gassing (release of carbon dioxide) that’s brought about when hot water is poured over the freshly roasted coffee grounds (Pour Over Coffee Basics – Brewing the Best Cup of Joe at Home!). If your coffee doesn’t bloom then you most likely have grounds that are old and stale as the carbon dioxide already has been released.
Do You Only Get a Bloom with Fresh Coffee?
The loss of carbon dioxide, as well as other gases, first starts as soon as the roasting process has been completed. But, it takes a few weeks for all of the carbon dioxide gas to escape the coffee grounds following the roast. It is the carbon dioxide and other gases that give flavor to the coffee, which is why you need to make sure that most of the gas remains in the beans for a longer period of time – Does Altitude Affect Coffee Flavor?
But, once the coffee is ground, gases like carbon dioxide can easily escape. This is the reason that most coffee drinkers grind the coffee beans (Can You Eat Coffee Beans? – Should you Eat them?) they use before brewing them to delay and slow down the degassing process. So, the answer is, the blooming of coffee can only be achieved with fresh coffee. The bloom also depends on the beans, since beans that have been around for a while will have more time for the gases to be released naturally. This is why older coffee beans tend to produce a weaker bloom – Arabica vs Robusta Coffee Beans – What Is the Difference?
Does the Bloom Affect Taste and Aroma of Your Coffee?
For many people, the coffee blooming is not just fascinating to look at; the chemical reaction also plays an important role in the brewing process. The hot water helps release once-trapped gas. The rich flavor of the coffee grounds is naturally extracted during the blooming. This can have a huge impact on the taste and aroma of the coffee.
Two factors affect the bloom of coffee grounds. Firstly, the carbon dioxide present in the beans tastes sour, which means when the grounds do not bloom before the brew, the gas that’s held infuses the coffee with the sour taste, further enhancing the flavor of the coffee. Secondly, carbon dioxide is a gas, repels the water and inhibits the coffee bean compound extraction that occurs during the brewing process (AeroPress Brewing Guide – How to Make AeroPress Coffee). This also has an impact on the taste and aroma of the coffee – Ultimate Comparison of Pour-Over vs Drip Coffee – Which Tastes Better?
Why Should You Let Your Coffee Bloom?
The main reason why you should always let coffee rest and bloom is to make sure it’s ready for the extraction of the pour-over. This is because it is better to let the gas off up-front. If you are in the habit of making coffee using fresh roasted beans (just a few weeks old), you are more likely to get coffee blooming – Can Coffee Cause Gas? Is it the reason for your Flatulence?
Even if you do not think about it while brewing, it is going to be a variable if you want to make that perfect cup of coffee. If you do not get a bloom, then it means that your coffee is stale or has been lying around for a long time. In other words, the coffee blooming is an indicator of the freshness of the coffee beans, which is something every avid coffee drinker looks for during the brewing process.
How Long Do You Let Your Coffee Bloom?
While this might vary depending on the type of beans you use, the ideal timeframe for how long you should let it bloom is anywhere between 15 to 30 seconds. During this time, pour a small quantity of piping hot water on the coffee grounds, and you will immediately notice a bloom start to form.
This is indicated by the foam that appears over the water in the press-pot when you manually brew your drip coffee. This bloom needs to stay for at least 20 seconds before you can stir the mixture with a spoon.
What Causes Bloom and What Other Gases are Released When Brewing Coffee?
Coffee can give off carbon dioxide for a period of two weeks once it has been roasted. This is a process known as degassing and is where most of the carbon dioxide trapped within the roasted coffee beans is released.
You will usually not see that bloom in a drip coffee maker. The coffee maker does not give the grounds enough time to bloom and the water oftentimes is also not hot enough.
Can You Get the Bloom with Ground Coffee?
The answer to whether or not bloom can occur with ground coffee is all going to boil down to when the coffee was ground. If the beans were ground a few weeks ago, then bloom is possible, albeit a weak bloom. However, if the beans have been ground for a longer period, then there are fewer chances of a bloom.
Not only can you get your coffee to bloom when you manually pour the water but you can also achieve it with a French Press. Slowly pour a small amount of the hot water onto your roasted coffee grounds in the French Press and let them sit for a few seconds so they have time to bloom (Can You Microwave Paper Cups with Coffee?).
Do Storage Conditions Impact Bloom?
It is important to pay attention to the temperature where you’ve stored the beans, mainly because the hotter the temperature of the bean storage, the more gas it will release during bloom. It is also important to note that darker roasts result in less gas being released due to the beans becoming oily during the roasting process.
Whether you are a casual drinker or a coffee addict, the blooming of coffee is a way for you to ensure that you are going to get a rich, flavorful cup of Joe with the coffee beans you have chosen.