For the best extraction and flow rate, it is recommended that you use a medium-coarse grind with a Chemex, particularly because of its unique filters. The Chemex can be used with other grind sizes, but it is likely to result in over or under extraction and give a taste or concentration to your coffee that is less pleasant.
There are many things that affect the flavour of a brew, even when you are using the same brewing method and device, but the size of the grounds is one that is easy to overlook. Different grind sizes are better suited to different coffee makers and brewing methods, so ensuring the right one can make a big difference.
This article will go into detail about the Chemex coffee maker – where it comes from, how it was designed and how it works – as well as how the grind size, roast and type of coffee can change the resulting brew when you are making coffee with your Chemex.
What is a Chemex?
The Chemex coffee maker is an all-in-one pour over device that allows you to brew a delicious coffee simply at home, although it is also popular in cafés. It is a well-loved coffee maker in part due to its stylish and attractive design as well as its efficacy when it comes to the pour over brewing method.
What is Pour Over Coffee?
As opposed to other coffee brewing methods, pour over coffee is made by allowing the hot water to percolate over the grounds as they sit inside a filter. Rather than steeping, fully immersed for a long time, the water passes through, extracting the oils and flavour as it travels so the resulting coffee is cleaner and more mellow.
Why Was the Chemex Coffee Maker Invented?
Invented in 1941 by the eccentric German chemist Dr Peter Schlumbohm, the Chemex was designed to make the pour over process simple and beautiful. This coffee maker is an accent piece as well as a utensil, and because it is a single, unified piece of glass, your coffee can be brewed inside without the need for any other equipment.
How Does the Chemex Work?
The Chemex coffee maker is hourglass-shaped, combining the forms of a large funnel and an Erlenmeyer flask, so a filter can be placed in the funnel and the coffee can collect below. The filter and coffee grounds rest inside, and water is poured into the top with all of the brewing happening within the device.
How Does the Chemex Filter Coffee Grounds?
Besides its unified shape, one of the major differences with the Chemex is the type of filters it uses. As opposed to the metal filters used in making espresso, or the metal plungers used to separate the grounds in a French Press, pour over coffee makers use paper filters, and the filters for the Chemex are quite unique.
How Are Chemex Filters Different from Other Pour Over Coffee Makers?
The filters used in a Chemex are 20-30% thicker than regular paper coffee filters and they have a texture that is almost like fabric. This means that they absorb much more of the oils and soluble elements of the coffee as they pass through, making the resulting brew cleaner and brighter.
Why Does the Chemex Use Medium-Coarse Coffee Grounds?
With other pour over coffee makers, you might use grounds that are finer but, because of the thick filters that it uses, the Chemex works better with a medium-coarse grind. Finer grounds will slow down the water flow too much and extract too quickly, resulting in a muddy and bitter brew.
Why is Extraction Important for Coffee?
Extraction is all about how much soluble coffee you get into your final cup, and the perfect extraction gives the right balance of flavour and intensity. If your coffee becomes over extracted it will be unpleasantly bitter and cloudy, but if it is under extracted there will not be enough flavour or concentration and your brew will taste watery.
Is Water Flow Rate Important for Pour Over Coffee?
One of the benefits of the Chemex is that it has been ergonomically designed to allow water to pass through at a consistent rate. This means that the water is extracting a consistent amount of soluble coffee as it passes through, so it is more predictable and reliable at making a nice, balanced cup.
How Does Grind Size Affect Extraction?
The size of the coffee grounds affects extraction because of the amount of surface area interacting with the water. The smaller the grind size, the greater the surface area and the quicker your coffee is going to extract, meaning more oils, flavour and soluble coffee is pulled into the liquid in a shorter space of time.
Does Grind Uniformity Affect My Coffee?
You might find that you are not getting the type of extraction that you expect from your Chemex, despite choosing the right grind size, which may be the result of inconsistent grounds. If your coffee has not been ground into uniform particles, the smaller ones can clog up the filter and cause over extraction in your brew.
How Does the Roast Affect My Coffee?
When the coffee beans are roasted for longer, they become darker, lose some caffeine and the intensity and bitterness of their flavour is increased. Lighter roasts will contain more of the origin flavour of the bean and will be more highly caffeinated, but will produce a mellower coffee.
What Roast is Best for Chemex?
Usually, a medium roast is recommended for a Chemex because it gives a nice balance of flavour. The Chemex uses the pour over method, which is better at bringing out the subtleties and nuances of flavour within beans that are more lightly roasted, but the thick filters also allow for good extraction from darker roasts as well.
What Variety of Coffee Bean is best for Chemex?
When it comes to bean variety, it is all about personal preference and what taste you like best. In general, Arabica varietals are smoother and sweeter, with notes of fruits or berries, whereas Robusta beans are stronger in flavour and more bitter.
Hi, I’m Jen Williams, chief editor and writer for ThirstPerk.com.
I’ve been drinking coffee and tea for most of my life, but it wasn’t until I started working at Thirstperk.com that I became an expert on the subject. I’m a total caffeine addict who has spent hours upon hours reading about and experimenting with the different types of coffees out there in my search to find the perfect cup of joe.
I’ve been a tea lover for as long as I can remember as well. I grew up in a house with a mom who loved to drink herbal tea, and I think that’s where my love for tea first began. These days, I’m always on the lookout for new and interesting teas to try, and I love experimenting with different brewing methods and flavoring combinations.