The bloom in pour-over: why fresh coffee needs longer.

What happens during the bloom

Roasting creates carbon dioxide, which stays trapped in the beans and escapes slowly over weeks. When hot water hits the grounds, part of that gas is released at once: the coffee bed rises and bubbles. As long as gas is escaping, it keeps water away from the grounds and the extraction becomes uneven. The bloom gives the gas time to escape before the main pour begins.

How much water, how long?

For the bloom, about two to three times the coffee dose is enough to wet all the grounds evenly. Shotbook plans with 2.5 times the dose, so 50 g of water for 20 g of coffee. The bloom phase lasts 30 seconds from the start of the first pour, then the next pour follows.

Fresh coffee: 45 instead of 30 seconds

The fresher the roast, the more gas is still in the coffee. If your coffee was roasted less than 4 weeks ago, Shotbook automatically extends the bloom to 45 seconds. All it needs is the roast date.

Example recipe: 20 g to 320 g

This is how Shotbook plans a pour-over with 20 g of coffee and 320 g of water (ratio 1:16). Times count from the start of the first pour:

Both versions finishing at about 3:00 is intentional: the longer wait at the start comes off the drawdown, the total time stays the same.