Invented by Peter Schlumbohm in 1941 in Chicago, USA. The design is both beautiful and functional. Probably the reason why MoMa New York exhibits it. Being a chemist, Schlumbohm understood extraction of flavour and caffeine.
The glass is designed to capture heat very well which is why we like the Chemex for larger brews that can be shared amongst friends.
The Chemex paper is slightly thicker than others. This leads to very clean brews, but also requires slightly coarser grind setting. Grind your coffee just before your brew. Make sure you store your full beans in a closed, zipped bag and at room temperature.
First, boil your filtered water to 95 degree Celsius. Grind your coffee beans at a medium to coarse level. Fold your filter paper and place it at the top of the Chemex. Wet the paper with hot water. This step helps the filter paper to stick to the sides of the glass, while it also gets rid of the residual papery flavours. Remember to dump the water before brewing.
Fill in the Coffee
Carefully distribute your coffee into the centre of your Chemex, avoiding the wet sides where it may stick. Give the Chemex a gentle push to flatten the top of your coffee dome.
Bloom & First Pour
Tare your scale and start your timer. Your first pour should be vigorous and wet all the dry grounds. This 'degasses' your coffee - it starts to bloom resulting in a better flavour in your finished brew. Your first pour should be double the amount of dry coffee. Wait for 30 seconds.
Every 30 seconds, add another 100 grams of water in circling movements until you finish with your final pour at 500 grams.
Let your coffee brew and filter through to the bottle of the Chemex, where you will notice the dripping will begin to finish up at around the 3 minute mark. Some brews may run faster or slower than this. But it all depends on how it tastes and how the coffee is extracting.
Check Your Brew
Once the coffee has poured through, check that your grinds bed is flat. An indication of how consistent your pour was. Notice if one side is higher or if there is a ditch in the middle, as some parts may be over or under extracted. The shape of the Chemex helps to cool down the filter brew. Give it a swirl, serve and enjoy!