The Chemex coffee maker was invented in 1941 and the iconic design remains unchanged today. Made of borosilicate laboratory grade glass, it is a sturdy heatproof vessel. Some coffee makers have plastic or metal parts that react with coffee oils and acids, but this is not the case with glass. For more than 70 years, generations have in turn embraced and ignored this simple coffee-brewing contraption. My Grandma had one, my Mom did not–and now I have one. The Chemex is in vogue again as pour over coffee gains popularity worldwide.
To brew coffee with a Chemex, all you need is the Chemex itself, a Chemex filter, ground coffee and 200F (93C) water. But is it really that simple? This depends on your coffee personality: Are you a Coffee Professor or a Coffee Artist?
The Coffee Professor (more like Lameen)
At heart the coffee professor desires repeatable results like with any scientific experiment. To this end, the professor begins by washing the Chemex with a coffee machine cleaning powder solution and rinses and dries it thoroughly to remove any previous coffee residue. Next, fresh filtered water is placed in a variable temperature gooseneck electric kettle set to 200F (93C). It only takes a few minutes to get to the right temperature and then the kettle shuts off on its own. With the equipment prepped and ready, the professor is ready to brew.
The professor takes a Chemex brand paper filter and inserts it with the triple layer resting against the pour spout channel. The gooseneck kettle is used to wet the paper filter as it rests in place. The filter is then removed, the hot water is discarded and the filter is reverently put back into its place. This serves to pre-heat the glass carafe as well as rinse the paper filter to get rid of any “bland” smells.
Although the Chemex is an affordable brewer (for coffee geeks), the professor will use a burr grinder that costs a lot more than the Chemex. This coffee grinder is calibrated to produce particles that are considered in the ‘fine drip’ coffee range. A kitchen scale is used to measure out 36g of good quality coffee beans, which are then freshly ground prior to the brewing process (remember, coffee begins to loose its optimal taste after a few seconds of grinding). The freshly ground coffee is then placed in the filter. The Chemex, filter and coffee are then placed on the scale and the tare on the scale is set to zero.
With the precise control of the gooseneck kettle, just enough water is dribbled over the ground coffee to moisten it. This allows the coffee to “bloom,” a chemical process where carbon dioxide is released. The fresher the coffee, the more it blooms. After a specific amount of time (30 seconds to 1 minute depending on coffee ideology) the professor moves from pre-infusion to a methodical wetting of the grounds. In a concentric motion, water pours evenly into the Chemex until it is near the top. This cycle is repeated until the scale records 25-30 US fluid ounces (730-800 grammes) of water. From coffee bloom to completion should take no more than 5 minutes. If the coffee drained faster, the grind was too coarse and if the coffee drained too slowly, the grind was too fine. In this manner the professor fine-tunes the Chemex brewing method.
The Coffee Artist (Samantha – the writer)
The coffee artist knows inherently what it takes to make a good cup of coffee through trial and error or through muscle memory over time. My mom called this type of estimation, “eyeballing it.” I fall squarely into this camp. I do not have the perfect coffee brewing equipment; I make do with what I have in the kitchen.
My kettle is heavy and hard to pour – It was a wedding gift. I boil the water and then pour it into a glass measuring cup that has an okay pour spout. I pre-wet the filter (barely) and then swirl and unceremoniously dump the hot water from the carafe. That is my nod to the pre-warm, pre-rinse, residue removal phase. I have a standard coffee scoop and I use 5 or 6 of those. My coffee is delicious and locally roasted with the roast date printed on the bag and since I do not yet own a burr grinder I buy it pre-ground.
The coffee smells so delicious in the Chemex that I cannot wait for it to bloom. I pause for maybe 10 seconds to admire the pretty brownie cake-like surface and then continue to pour until it fills the Chemex to the top. As it drains out, I add more hot water until the level of coffee in the carafe reaches the bottom of the wooden collar. Then I compost the filter and spent grounds. While I enjoy the brew process, my desire is to fill a mug with delicious freshly brewed coffee as soon as possible. If I took a few shortcuts along the way, is mine better/worse/different than the coffee professor’s exacting methods?
Vive La Difference!
I think there is room for many coffee brewing styles in this world. When I go to a pour over bar I appreciate that they brew with accuracy and the goal is to attain an enjoyable and repeatable cup of coffee. Now that you know about the Chemex method of coffee brewing, you are welcome in either camp, just don’t forget to bring fresh coffee.
This article, with very slight editing by moi (Lameen) was produced by Samatha Joyce, a writer for seattle coffee gear – http://www.seattlecoffeegear.com/