Rarely does a day go by that I don’t hear about using less grinds to make the coffee
weaker. This does have its place, and if your ratios are correct an often overlooked aspect is if you are using the proper grind consistency for the brew method of choice, or if your water is at the proper brewing temperature.
In this article I’d like to touch on;
How extraction works?
What is proper extraction?
How to properly extract, and get weaker coffee!
How extraction works;
Coffee extraction occurs in two stages. First the water contacts the grounds, which rapidly washes away at the coffee solids and displaces the gases. Secondly, the coffee absorbs water and swells which drives off the carbon dioxide where the volatile aromas are trapped within the grounds and migrate into the liquid by diffusion.
Roughly half of your extraction occurs almost immediately.
Rate of extraction is determined by ground size (how fine you grind), water temperature, agitation, and brewing ratio (percentage of coffee to water)
So lets assume we have the least amount of variables possible. Our coffee has the proper and consistent grind for the brew method we are using, our coffee is fresh, our brewer is dispersing water evenly across all the grounds, and our water temperature is stable and consistent (in volume). Our only variable is how much coffee we are using.
What is proper extraction?
Most coffee associations including Norwegian, Europe, and American recommend an 18%-22% extraction. Simply put I would suggest beginning with a 1:17 ratio. Measuring both the coffee and the water by mass. In other words, using 1 gram of coffee for every 17 grams of water. In this range you have the highest chance to maximize sweetness and minimize bitterness.
If we are using less coffee for the same amount of water we are allowing longer contact time and the coffee will gradually increase in bitterness. In the first half of your brew, you are extracting acids and sugars, as your brew continues and all your sugars and acids have been extracted, all that remains to be extracted from the coffee are it’s bitter components.
So how do I properly extract and get weaker coffee!?
The key word is dilution.
It is ok if you find coffee brewed at a 1:17 ratio still to strong. You do have some flexibility, trying going down a little in your coffee weight, but don’t stray from it to far. It is far more beneficial to brew at the proper rate and add hot water to your already brewed coffee after. This way you can extract the oils out of the coffee allowing for a well-balanced cup and simply dilute it to your desired strength. This will preserve the flavor more and result in a more enjoyable cup.
What are other ways you have successfully brewed coffee for people who like it “weaker”?