Chemex Pour-Over

The Chemex a glass coffeemaker used to brew pour-over coffee. Thanks to its dense filter, the coffee will be light and clean, but also rather strong due to prolonged contact with water.

Chemex, like any filter brewing method, is good at helping to reveal floral, berry and fruit aromas.

Check out this video to learn more about the Chemex:

Grinding

The grind for Chemex is medium-coarse, slightly finer than the grind for a French press. It should look like sea salt. You can always adjust the grind size to brew the best coffee for your tastes.

Coffee Dosage

The optimal coffee dosage for a standard 2-cup Chemex is 1.11 oz (31.53 grams).

The ratio of coffee weight to finished coffee is always the same—1:17, which is 2.07 oz (58.8 grams) of beans per 33.8 fl oz (1 liter) of water. To determine the dosage for each specific case, you just need to calculate the proportions, but the grind size may have to be changed slightly. It is worth trying different options and focusing on how long brewing takes.

Below we provide the water infusion calculations based on regular and strong coffee ratios (1:17 and 1:11).

Chemex Pour-Over Coffee to Water Ratio

Water Temperature

The optimum temperature for making coffee in a Chemex is 200-203°F (93-95°C). To achieve this temperature, you need to either bring the water to a boil and then cool it for a minute, or use a good water thermometer.

The temperature of the water significantly affects the taste, and the choice of temperature also depends on the particular type of coffee. We can't give any universal recommendations, so we recommend experimenting: a difference of one degree can give coffee brightness, sweetness, and balance, or it can leave an unpleasant aftertaste.

Placing Coffee in a Paper Filter

We recommend that you pour 4-6 fl oz (100-200 ml) of hot water through the filter to completely dampen the filter (and then pour out the excess water) even before adding ground coffee to a paper filter. This is to remove any possible paper taste.

After that, you need to pour coffee into the filter and shake the Chemex lightly so that the coffee is smoothed.

Pre-Wetting (Blooming)

The first stage of brewing is pre-wetting. It helps to improve the taste of coffee and make the results more consistent, especially if the coffee was roasted less than a month ago. This step allows excess gases to escape from the coffee so that during extraction they do not affect the result.

First, put the Chemex on the scale and zero it, then start the timer and gently moisten the coffee with a small amount of water—about 2.5 fl oz (75 grams) of water, and then wait 30 seconds until all the water is absorbed into the coffee. When this happens, you need to immediately start brewing.

The volume of water for pre-wetting is usually calculated at three times the weight of the coffee itself. That is, if you use 1 oz (28.3 grams) of coffee grounds, then the weight of the pre-wetting water will need to be 3 oz (90 ml).

Infusion of Water

Water infusion is the most critical part of the whole process since you need to simultaneously monitor the time and weight of the water.

There are several methods of infusion: interval, gradual, and one-time.

The one-time method is when water is poured in in a circular motion all at once, the interval method is when water is poured in in certain portions, and the gradual method is a compromise between a one-time and an interval method.

After pre-wetting, you need to gently, start pouring water into the coffee in a circular motion in a thin stream, starting from the center and moving closer to the edges.

The total brewing time, including pre-wetting, should be 3-3.5 minutes, during which time all the water in the filter should pass through the coffee into the Chemex. However, this time will change if you make more or less coffee.

At the very end, you need to throw out the used filter and grounds, shake up the drink for oxygenation, and enjoy the taste!