How to Brew Large Batches of Coffee
Use a Chemex or French Press to Brew Enough Coffee to Share with Loved Ones or Your Future Self
We spent a year perfecting our pour over dripper and more than a decade refining our method to help you produce delicious coffee, one mindful cup at a time. But sometimes, you want to brew enough coffee to share or drink throughout the morning. Those times, we recommend using an eight-cup Chemex or an eight-cup French press. Below, you’ll few tips to help ease the process. (And if you need more detail about brewing with each method, visit our Chemex Brew Guide or French Press Brew Guide.)
CONSIDER GRIND SIZE
The main concern when it comes to brewing coffee in larger quantities is that more grounds lead to overextracted coffee. This can happen because the larger amount of ground coffee slows the flow of water, thereby “steeping” the coffee for too long. A change in grind size prevents that.
For both the Chemex and French press, make the grind just slightly more coarse than for smaller servings—think microadjustments, not macro, on your grinder.
COFFEE-TO-WATER RATIO
The next step is to adjust the water-to-coffee ratio based on the coffee you are using and your preferred brew strength.
For Chemex, when you’re brewing darker roasts or blend coffees, aim for a 1:12 ratio, that is, one unit of coffee per twelve units of water. (This means, for each cup, use 30 g coffee to 350 g water.) To brew a single origin, which you will want to make slightly "lighter" in order to let the nuanced flavor profile come through, add more water, aiming for a ratio of 1:15. (Use 24 g coffee for each 350 g cup.)
For French press, the same principle applies. We like our blend coffees to have a ratio somewhere between 1:12 to 1:14. For a single origin, 1:15 is again the magic proportion.
EXTRACTION TIME
An eight-cup Chemex will take slightly longer than the typical three to four minutes to brew, because the water has to work through more coffee grounds. Try to hit somewhere between four and five minutes, and you should be safe from overextraction. If the process is too lengthy, try grinding your coffee a little more coarsely next time.
For French press, stick to a four-minute brew time. Never a second less.
WARM YOUR VESSEL
Maintaining as constant a temperature as possible during the brewing process is best for even extraction, especially with larger batches of coffee. Pre-warm your vessel, whether it’s the Chemex or French press. Pour out the hot water just before starting to brew.