"Degas your fresh grounds for optimal taste."
The Coffee Bloom
Coffee bloom is a term that might come up in your search for the ideal brewing conditions. Those who like to use pour over brewing techniques are the most likely to employ them. To do this, pour a portion of the water over the coffee and let it rest for a few moments (around 30 seconds) before continuing to brew.
You can tell when coffee is "blooming" because the grinds expand, and bubbles form on the surface. The beans emit carbon dioxide (CO2), which may be seen as bubbles.
Every coffee bean contains CO2. Gas begins to escape from the beans the moment they are roasted. The darker the roast of your beans, the less carbon dioxide they contain.
The gas has a negative dual effect on the taste of your beverage:
Carbon dioxide is a sour gas. It may be nice in a glass of carbonated water, but it's not the taste we're going for with our high-quality beans.
The gas prevents any moisture from reaching the coffee. For the water to extract all the flavor compounds needed for your brew, the gas must first be released.
Because of this, releasing the gas during the brewing process is worth an extra 30 seconds.
After roasting, coffee is degassed, but you still need to do the last step in the brewing procedure.
How To Bloom Coffee
Prepare your preferred pour-over coffee equiptment with freshly ground beans.
Measure out twice as much water when it reaches the ideal temperature (so for 25g of beans, 50g of water).
Add some of the water to the coffee.
Hold on 30 seconds. The coffee should puff up and release gas in the form of bubbles.
Add the remaining water and continue brewing as usual.
Nonetheless, if there are many bubbles, the coffee is likely to be quite fresh.