BREWING GUIDE: CHEMEX
The Chemex Coffeemaker was invented in 1941 by Dr. Peter Schlumbohm PhD. Made simply from non-porous, borosilicate glass, it brews coffee without imparting any flavors of its own. On permanent display at MOMA New York and other fine museums, it is truly a work of art.
The Chemex consists of an narrow-waist glass flask and uses proprietary paper filters, made of chemically bonded paper (of thicker-gauge paper than the standard paper filters for a drip-method coffeemaker).
We love the Chemex for the clean and crisp cup it produces.
Rinse filter with boiling water and discard water. Replace filter (positioning the three folds toward the spout). Rinsing the filter removes any paper taste of the filter and the hot water will preheat the Chemex.
Weigh about 52 grams coffee to be ground. Fill kettle and heat water. Pro tip: we weigh out slightly more coffee than will be used, often a gram or two is lost in the grinder.
GRIND AND WEIGH
Grind coffee. The particle size should be similar to kosher salt (coarser than the Kalita grind, finer than a French Press grind). Weigh 50 grams of coffee into Chemex. Create divot in bed and tare scale.
Just after boiling, remove kettle and let water settle. Start timer and pour enough water to just saturate coffee bed. Let bloom, or expand for 30 seconds. Allowing the coffee to bloom ensures even water dispersion and a delicious cup. Pro tip: try to use only 45-50 grams of water to cover all coffee, this will leave you with the correct amount of water to complete the brewing on time.
Pouring slowly in concentric circles, add enough water to raise slurry about halfway up the cone. Continue adding water slowly in stages (also called pulse brewing), submerging the crust as you go. After crust has dissipated, pour into center of Chemex, raising the level of the slurry if needed toward the end in order to add all water in appropriate time. Try to add all water by 3:00.
Once you’ve added 800 grams of water, give it a final stir and let drain (aiming for flat or slightly domed bed). The final brew time should be in the range of 4:30-5:00 depending on the coffee.
SERVE AND ENJOY!
Remove filter and serve. Enjoy!
As with any pour-over, the water level will greatly affect how your extraction progresses, the larger Chemex is more susceptible to heat loss because of the large surface area the cone creates. Also, flow rates can be a bit slower than other pour-over methods, which is why we use a coarser grind. However, if you find your extraction is taking too long, you can speed things up by raising your kettle and pouring into the center of the cone. Naturally, this produces more agitation, so use this technique with discretion.