What is Blooming?

In order not to be overwhelmed with detail, we have reserved some of the blooming-related sections for our readers who just want to specialize and we have written them in this color.

Blooming directly affects the flavor of coffee!

Blooming can be translated as flowering or blooming of the flower’s leaves in Turkish. When brewing coffee, it is the name given to the release of carbon dioxide and other gases in the contact of ground coffee with water. In appearance, it resembles the foaming, in other words, bubbling of an acidic drink.

What Causes Blooming?

When roasting coffee, there are many chemical changes with the breakdown of the ingredients in the green core.  Volatile aromatic compounds (gases) form the aroma of coffee. Green coffee contains more than 200 volatile gases. The purpose of roasting is to optimize the flavors of the soluble chemistry of coffee. Dissolved solids make the taste of brewed coffee. Soluble oils and essential aromatic compounds form the aroma. Parts of the nucleus cellulose form the body (weight) of the coffee. These gases do not harm human health. Researchers have identified over 800 volatile substances in roasted coffee (Scott Rao 2014:8). The most important of these gases is carbon dioxide.  The carbon dioxide accumulated in the roasted coffee is released out.  This stage, which is given the degassingname , is important for the flavor of the coffee. When you pick up a shot espresso that hasn’t completed its degassing, you can observe bubbles coming out from below to the surface, like coke. This is due to CO2, which it cannot expede. Coffee that’s completed its degassing doesn’t foam like this. Degassing is when coffee is the nucleus, expeling its co2. Blooming, on the other hand, is when ground coffee is in contact with water and expels its co2. As soon as the coffee is ground, it releases more CO2 and is exposed to more oxygen with the increase of the surface area. Oxygen contact means coffee gets stale. Therefore, stop grinding your coffee in your brews and start brewing as soon as you grind it. In this way, with water, you will have lowered the aromas of the glass.

Is Blooming Necessary?

Carbon dioxide has a sour/bitter taste and covers the aromas of coffee. Therefore, coffee needs to do both its degassing and its blooming. Thus, the carbon dioxide that covers the aromas of the coffee will be expelled from the coffee. 

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How Blooming Occurs

Pour 60-80 ml of water over your ground coffee. Wait until 20s. While you wait, you will observe that the surface of the coffee is puffing, bubbles are coming out. That’s blooming. The coffee  One of the biggest differences between manual brewing and machine brewing is that bloming can be allowed in manual brewing.

How to Do The Right Blooming?

One thing we observed as the Coffee Project is that the surface of the coffee is flat before it starts brewing. As a result of our experiments, we observed that opening (pitting) the surface of the coffee in a spiral releases the gases of coffee more easily. In shape,

1. To be able to dispose of CO2 in the coffees (almost half the coffee in the tank) that are at the bottom  must exceed the coffee at the top. This makes it difficult to throw CO2 to the surface. It can be observed that coffee in particular forms a crust on its surface some time after it is wet. This shell releases co2, which is already difficult  it makes it more difficult.

2. In the second way, when the coffee surface is pitted conically, the CO2 release of coffee without weight is much easier.

Factors Affecting Gas Output

In some cases, the amount of gas output from coffee varies. There may be several different reasons that affect this.

1. Freshness of Coffee

It is one of the most important factors. You can observe that there is more blooming when brewing fresh coffee. If you’ve got all the other variables right, but it’s blooming oz, it’s an indication that coffee is getting stale.  You can check out the freshness of coffee chart here.

2. Roasting Profile

Lighter roasted coffees have less CO2 on site than darkly roasted coffees. Dark roasted coffees are more blooming.

When roasting coffee 1. The reason for the snap (first crack) is that the moisture in the center of the core breaks the core and comes out. If it continues to scorch, 2. Second crack is heard. The reason for the 2nd cracking is that the CO2 accumulated in the center this time comes out. 

3. Temperature of Water

If you use water that is hotter than it should be, the coffee will burn and blooming will not take place as desired (URL1).

4. Type/Origin of Coffee Bean:

Depending on the origins of coffee beans, their blooming may vary (URL2).

CO2: Carbon dioxide


Scott Rao, (2014) ” The Coffee Rosater’s Companion,” Canada

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