CHEMEX BREW GUIDE
HOW TO BREW CHEMEX LIKE A PRO
1. Grind size:
In order to yield a high quality brew from a Chemex, the grind size should be slightly finer than the French press, but should still look like granules and not sand. The Chemex is prone to brews stalling completely if your grind is too fine. And a grind that is too coarse will under extract and will pour through too fast.
2. Coffee dose/brew ratio:
As I mentioned in the French press brewing guide, choose your brewing ratio according to taste. This time keep in mind that Chemex produces a light-bodied brew, so you may want to start with a 1:10 ratio (1 gram coffee per 10 ml of water). Increase the coffee dose or use less water to achieve your preferred taste.
3. Water temperature:
Try brewing with water between 90-96 degrees celsius to begin with. I encourage you to experiment with temperature if you have an accurate way to do so because it can change the cup dramatically for some coffee lovers.
4. Brew time:
The extraction time on a Chemex is between three to five minutes depending on your pouring technique and grind size. You will have to experiment with the variables to consistently achieve your preferred brew time.
Start by heating your water to the desired temperature and grind the desired amount of fresh coffee appropriately. Place the filter correctly inside your Chemex – there is a complete Filter Folding 101 section on how to fold the filter. Always rinse the filter to reduce any tastes that may affect the brew; this will also warm up the device. And then add the coffee to the brewer.
For the next step I highly recommend using a gooseneck kettle. Start pouring the water (90-96º) in circles from the center outwards. For the first pour remember to add double the amount of water to coffee you are using and let it pre infuse for 30 seconds. If your coffee is fresh enough, you will see an amazing bloom, which is the reaction of the coffee when water is added and the carbon dioxide is released.
Keep pouring slowly in circles avoiding the walls of the brewer. Do not add all the water at the same time, I recommend what is known as a pulse pour – add 30 grams of water each time and wait for a few seconds, this will create a better extraction, but don’t let the grinds go dry otherwise you will lose the ideal temperature. Reach the desired amount of brew, dispose the spent grounds and serve. Most important of all, enjoy it and take time to appreciate the changes when drinking the coffee as the temperature drops.
Personally, this is the brewing method I enjoy the most due to its clean finish and aroma that is maximized by the Chemex shape. Try it with a Geisha and you will know what magic tastes like. Alternatively, experiment with other Chemex filter types such as Coffee Sock‘s organically grown, untreated cotton version.
THE HISTORY BEHIND THE FANCY DESIGN
Who says that a chemist can’t get involved in designing coffee brewing methods? The Chemex is a classic and elegant brewing device that was designed by the German chemist, Peter J. Schlumbohm. It may seem like a device that was born out of the third wave brewing movement, but it has been in production since 1941.
Schlumbohm is the owner of more than 3000 patents due to his numerous inventions, but the Chemex and the water kettle are one the most famous. They are even part of permanent collections in some museums, like the Museum of Modern Art in New York, the Smithsonian, the Corning Museum and the Philadelphia Museum.
In order to create this coffeemaker, Schlumbohm was inspired by two laboratory apparatus: his laboratory glass funnel and his Erlenmeyer flask. He added an air channel to the funnel in order to leave space for the air displaced by the liquid dripping into the vessel to escape easily. He added a “belly button” to the Erlenmeyer and then combined it with the modified glass funnel. Add the beautiful wooden handle and voilà, you have a one piece, heat proof, borosilicate glass coffee brewer called Chemex that has always and continues to rival new and old drip filter devices – but enough about history, let’s get down to the how to use this masterpiece and discuss the beautiful brew that you can make with this device.
WHAT TO EXPECT FROM A CHEMEX
Chemex is a pour-over method, which means that the water passes through a bed of coffee and a filter, normally made out of paper. In contrast to say a French press, the Chemex will give you a remarkably clean cup of coffee. Chemex paper filters are 20-30% heavier than other filters so they retain more of the suspended oils during the brewing process and solids cannot pass through the filter.