Chemex 6 Cup Paper Filter Brew Guide
The Chemex was designed over 60 years ago by a German chemist named Dr. Peter Schlumbohm. The filter brewer is inspired by the Bauhaus Art movement, and is celebrated in modern art circles for the beauty of its design.
The Chemex uses a specially bonded filter paper. It is heavily constructed to restrict oils and sediment, yielding a very clean cup. The large Chemex has an excellent geometry for brewing; the bed of coffee has a large surface area, the filter has a ‘v’ shape, and a large exit hole – this allows for grind size and water ratio to dictate the overall brew time. Meaning, basically, if you treat the chemex well, it will treat you well – get the basics right and you’ll get a great cup of coffee every time.
So let’s get to it…
PREPARING TO BREW
Their uniqueness of geometry means the large Chemex is best used for large brews of 500-700grams of water, while the v60 is ideal for smaller filter brewing. (we prefer not to use the small Chemex).
Filter brewing, as is generally the case with coffee, requires some prep work. When the water first contacts the grinds everything should already be set up for success. we can’t stress enough how important it is to use controlled ratios of water and coffee…this means scales!
You can pour your boiled water from either an electric jug, or transfer hot water to a separate pourer if you want a more accurate pouring spout.
Boil the jug while you are preparing the brew. The brew water must be just off the boil – coffee needs around 94-96 degrees to correctly extract desirable flavours, so letting the boiled jug sit for 1 minute achieves optimum temperature.
If using a seperate pourer kettle, pre-heat the pourer before filling with brew water. Once you are ready to start pouring, discard the preheat water and refill with freshly boiled water, this ensures the pourer won’t cool your boiled water.
Grind your coffee to a course plunger grind. Grind size dictates brew time – if the coffee is too coarse it will brew too fast and produce underdeveloped flavours like sourness. If it is too fine, bitterness will dominate. Anything over 4 minutes is too long for a brew, so coarsen up your grind if this is happening.
Grind size dictates brew time: For a plunger the grind should be much coarser than for espresso
Fold the filter paper so the 3 sides cover the spout of Chemex to allow air to escape during brew.
Rinse the filter paper with plenty of hot water to remove papery flavours and leave this rinsing water in the Chemex to pre-heat it. Empty just before brewing.
1) Set the Chemex on the scales and dose the ground coffee into the wet filter.
2) Start your timer as you start the first pour. Pour in around 80grams of water, or, twice as much water as there is coffee (just enough to wet it all). The coffee will start to swell and rise – this is the bloom, a process of readying the grinds for extraction. It is important that all the grind is saturated. You can ensure this by gently spooning the grinds side to side and pulling the grinds from the bottom up to the surface: mixing but not stirring. The bloom should take 20-30 seconds, after this it will begin to extract. At 30 seconds, you should start to add more water. Don’t let the coffee dry out or it will taste bad.
It is important when pouring not to pour onto the paper as it will not enter the bed of coffee. Be sure to pour in circles on the grinds, focusing your pour towards the centre and the darker areas.
3) With a total ideal brew time of around 4 minutes, you need to consistently top up the water level, aiming to use it all by about 2 minutes. Pouring at 30 second intervals is a good way to ensure consistency. The first pour following the bloom should fill to the top of the glass, and from there continue with small top ups.
4) Enjoy the delicious fruits of your labour.
EXTRA FOR EXPERTS: If you have scales and want some extra tips, follow the barista guide below
Coffee: 41 grams. Water: 700 grams. Ratio: 1:17
– 0:00 bloom pour to 80ml
– 0:30 pour to 400ml
– 1:00 pour to 500ml
– 1:30 pour to 600ml
– 2:00 pour to 700ml and stir in any high and dry grinds
– 3:00 some people like to do a circular stir to create a round dome in the coffee bed
– 4:00 remove filter and grinds from pourer as bed dries out, the brew is officially finished when the trickle turns into drips
Experiment with brew time, grind size and ratios to find the most desirable flavours of each coffee origin, but write it down if for next time!
September 24th, 2014