The Chemex Brewing Guide
Like an auto-drip machine or a melitta/hario cone, the Chemex is a pour over method of brewing coffee. The Chemex offers a few distinct advantages:
- easy-to-clean;
- all glass;
- water temperature control
Overall, Chemex brewing will provide you with a richly flavored, complex, and clean tasting cup of coffee. Here’s how to do it:
What You’ll Need
Fresh roasted coffee
A measuring scoop or scale (preferred)
Chemex Brewer and filter
Cups
A burr grinder
A kettle or hot water heater
Step 1
Presoaking, Preheating
To place a clean filter in the Chemex, position the filter in a cone by laying three sides against one another leaving one side alone (instructions are on your Chemex Filter box). The three sidedpart should be against the Chemex pour spout.
Pour hot water through the filter to get out the papery taste and preheat the Chemex. You should also preheat the cups at this point.
Step 2
Weighing/Dosing
To make two 10oz cups, you will need 36g of coffee (5-6 tbs) and 20oz of water. If you want to make more or less coffee, use this ratio:
4oz of water for every 7.2g (about heaping 1 tablespoon) of coffee.*
Step 3
Grinding
Chemex require a paper filter grind (medium-fine). You can fine tune that grind, however. The grind should allow all the water to pass through the grounds in 3-4 minutes. If it’s passing through too fast, make the grind finer; if it’s passing through too slow, make it coarser.
Step 4a
Prewetting (the Bloom)
After placing the grounds in the presoaked filter (make sure there is no water in the Chemex!), add a small amount of hot water. The water should be 30 seconds off the boil (200F-205F). If the coffee is fresh roasted, the grounds will swell up giving off gas. Allow 15-30 seconds for this to happen.
Step 4b
Brewing
For 36g (5 to 6 tbs) of coffee, add enough water to reach the bottom of the bubble on the Chemex. That should be 20oz of water. If you are adding more or less, use the following ratio:
4oz of water for every 7.2g (about heaping 1 tablespoon) of coffee.*
Set a timer for 4 minutes and add water. If it finishes too fast you can either add more water or make the grind finer; if it finishes too slow you can either add less water or adjust the grind coarser.
Step 5
Composting…YOU’RE DONE!
Compost those filters! Spent coffee grounds are low acidity (the acids are in your brewed cup), organic matter that your garden will love!
You should have a nice dome shape to the filter and a very slow (to no) drip of coffee from the filter to the pot. At this point, pour your coffee into your preheated cups and enjoy!
* For our chemex brewing ratio, we use a 1.8 grams of coffee to 1 ounce of water. So, for 20 ounces of brewed coffee (two mugs), you would need 36 grams of beans. The chemex, in our experience, performs best at this ratio, but you can up it or lower it. Just make sure to adjust your grind to keep the timing around 4 minutes.
