Brewing Regular Coffee with a Chemex Brewer

Quick answer

• Yes, a Chemex brewer is excellent for making “regular” drip-style coffee.
• It excels at producing a clean, bright cup by filtering out oils and sediment.
• The key to good “regular” coffee in a Chemex lies in proper technique and fresh ingredients.
• Focus on water temperature, grind size, and coffee-to-water ratio for optimal results.
• Regular maintenance and cleaning ensure consistent flavor.

Who this is for

• Coffee enthusiasts looking for a cleaner, more nuanced cup than a standard drip machine.
• Home brewers who want to elevate their daily coffee ritual with a simple yet effective method.
• Anyone curious about how to achieve a bright, aromatic coffee flavor at home.

What to check first

Brewer type and filter type

Your brewer is a Chemex, a glass carafe with a distinctive wooden collar. It uses proprietary thick paper filters, available in various shapes. These filters are crucial for the Chemex’s clean cup profile, trapping more oils and fines than typical basket filters. Ensure your filters are the correct shape for your Chemex size (e.g., square or circle) and are placed properly to prevent channeling.

Water quality and temperature

The water you use significantly impacts taste. Filtered water is recommended to remove impurities that can impart off-flavors. For brewing, aim for a water temperature between 195°F and 205°F (90.5°C to 96°C). Water that is too cool will result in under-extraction and a weak, sour cup. Water that is too hot can scorch the coffee grounds, leading to a bitter taste.

Grind size and coffee freshness

The grind size for a Chemex should be medium-coarse, resembling sea salt. Too fine a grind can clog the filter, leading to over-extraction and a bitter brew, or even cause water to back up. Too coarse a grind will lead to under-extraction, resulting in a weak and sour cup. Always use freshly roasted whole bean coffee and grind it just before brewing for the best flavor and aroma.

Coffee-to-water ratio

A common starting point for Chemex brewing is a ratio of 1:15 to 1:17. This means for every gram of coffee, you use 15 to 17 grams (or milliliters) of water. For example, using 30 grams of coffee would require 450-510 grams of water. Adjusting this ratio can fine-tune the strength and flavor of your coffee. A lower ratio (e.g., 1:15) will result in a stronger cup, while a higher ratio (e.g., 1:17) will yield a lighter brew.

Cleanliness/descale status

A clean Chemex is essential for good coffee. Residual coffee oils can turn rancid and impart bitter, unpleasant flavors. Wash your Chemex carafe thoroughly with soap and warm water after each use. If you have hard water, mineral buildup can occur. Descaling your brewer periodically, typically with a vinegar and water solution or a commercial descaler, will remove these deposits and ensure pure coffee flavor.

Step-by-step (brew workflow)

1. Heat your water: Fill your kettle with filtered water and heat it to your desired brewing temperature, ideally between 195°F and 205°F (90.5°C to 96°C).

• What “good” looks like: Water is at the correct temperature, not boiling vigorously.
• Common mistake: Using water straight from a rolling boil, which can scorch the coffee. Avoid this by letting the kettle rest for 30-60 seconds after it boils.

2. Prepare the filter: Place the Chemex filter into the top of the brewer, ensuring the three-layered side is against the spout.

• What “good” looks like: The filter sits snugly and evenly in the brewer.
• Common mistake: Not unfolding the filter correctly, which can lead to uneven water flow and extraction. Always ensure the thickest part of the filter is aligned with the spout.

3. Rinse the filter: Pour some hot water over the filter, wetting it completely. Discard this rinse water.

• What “good” looks like: The paper taste is rinsed away, and the filter is seated properly.
• Common mistake: Forgetting to rinse the filter, which can leave a papery taste in your coffee.

4. Add coffee grounds: Weigh your freshly ground coffee (medium-coarse) and add it to the rinsed filter. Gently shake the brewer to level the grounds.

• What “good” looks like: The coffee bed is flat and even.
• Common mistake: Leaving the coffee grounds uneven, creating high spots and low spots that lead to uneven extraction.

5. Bloom the coffee: Pour just enough hot water (about twice the weight of your coffee) over the grounds to saturate them evenly, starting from the center and spiraling outwards. Wait 30-45 seconds.

• What “good” looks like: The coffee grounds expand and bubble, releasing CO2.
• Common mistake: Pouring too much water during the bloom, which can lead to premature dripping and poor extraction.

6. First pour: After the bloom, begin pouring the remaining hot water in slow, concentric circles, starting from the center and moving outwards. Avoid pouring directly onto the filter paper.

• What “good” looks like: A steady, controlled stream of water that maintains a consistent level in the brewer.
• Common mistake: Pouring too quickly or aggressively, which can create a “waterfall” effect and lead to channeling.

7. Subsequent pours (if needed): Continue pouring in stages, maintaining a consistent water level. Aim to finish pouring all your water within 2.5 to 3.5 minutes, depending on your batch size.

• What “good” looks like: The water level is managed, and the brew time is within the target range.
• Common mistake: Overfilling the brewer, causing water to overflow or drip too quickly.

8. Let it drip: Once all the water has been poured, allow the remaining water to drip through the coffee bed until the flow has mostly stopped.

• What “good” looks like: The water has fully drained, leaving a relatively dry puck of coffee grounds.
• Common mistake: Allowing the brew to drip for too long after the main flow stops, which can extract bitter compounds.

9. Remove the filter: Carefully lift the filter with the spent grounds and discard it.

• What “good” looks like: The filter is removed cleanly without grounds spilling into the brewed coffee.
• Common mistake: Not letting it drip sufficiently, leading to grounds falling into the carafe when removing the filter.

10. Swirl and serve: Gently swirl the Chemex carafe to ensure the coffee is evenly mixed. Serve immediately.

• What “good” looks like: A homogenous brew with consistent flavor.
• Common mistake: Not swirling, which can result in the coffee being stronger at the bottom than the top.

Common mistakes (and what happens if you ignore them)

Mistake	What it causes	Fix
Using stale coffee	Flat, dull, or bitter flavor; lack of aroma.	Use freshly roasted whole beans and grind them just before brewing. Store beans in an airtight container away from light and heat.
Incorrect grind size (too fine)	Bitter, over-extracted coffee; slow drip rate; potential overflow.	Use a medium-coarse grind. If it’s too fine, adjust your grinder to a coarser setting.
Incorrect grind size (too coarse)	Weak, sour, under-extracted coffee; fast drip rate.	Use a medium-coarse grind. If it’s too coarse, adjust your grinder to a finer setting.
Water temperature too low	Under-extraction, resulting in a weak, sour, and thin-bodied coffee.	Ensure your water is between 195°F and 205°F (90.5°C to 96°C). Let boiling water rest for 30-60 seconds.
Water temperature too high	Over-extraction, leading to a bitter, burnt, or astringent taste.	Use a thermometer or let boiling water rest for 30-60 seconds to bring it into the ideal range.
Uneven pouring during bloom	Inconsistent saturation of grounds, leading to uneven extraction and potential channeling.	Pour water slowly and evenly to saturate all grounds, ensuring no dry spots.
Aggressive or uneven pouring	Channeling, where water finds paths of least resistance, leading to uneven extraction.	Pour in slow, controlled concentric circles, avoiding the filter paper. Maintain a steady water level.
Not rinsing the filter	A papery, unpleasant taste in your brewed coffee.	Always rinse the Chemex filter with hot water before adding coffee grounds. Discard the rinse water.
Overfilling the brewer	Water backs up or drips too quickly, leading to inconsistent extraction.	Pour water in stages and avoid filling the brewer beyond capacity. Aim for a total brew time of 3-4 minutes.
Not cleaning the brewer regularly	Rancid coffee oils build up, imparting bitter and stale flavors.	Wash the Chemex carafe with soap and water after each use. Descale periodically to remove mineral deposits.
Brewing with tap water (hard water)	Off-flavors from chlorine or mineral buildup, affecting taste and brewer longevity.	Use filtered or bottled water for brewing.
Not swirling the final brew	Inconsistent flavor, with coffee being stronger at the bottom than the top.	Gently swirl the carafe after brewing to ensure all coffee layers are mixed evenly before serving.

Decision rules (simple if/then)

• If your coffee tastes sour and weak, then increase your coffee dose or decrease your grind size because you are likely under-extracting.
• If your coffee tastes bitter and harsh, then decrease your coffee dose or increase your grind size because you are likely over-extracting.
• If the water drains too quickly through the grounds, then your grind is likely too coarse because it’s not offering enough resistance.
• If the water drains very slowly or backs up, then your grind is likely too fine because it’s creating too much resistance.
• If you detect a papery or unpleasant taste, then you likely skipped the filter rinse step because the paper imparted its flavor.
• If your coffee tastes dull and lacks aroma, then your coffee is likely stale because the volatile aromatic compounds have degraded.
• If your coffee has an off-flavor, then check your water quality and ensure you are using filtered water because tap water can introduce unwanted tastes.
• If your brewed coffee has visible sediment, then your filter might not be seated correctly or you may be using too fine a grind, allowing fines to pass through.
• If your coffee tastes inconsistent from cup to cup, then ensure you are using a consistent coffee-to-water ratio and brewing method each time.
• If your Chemex has a film or residue, then it needs cleaning because coffee oils have built up and will affect future brews.
• If your water temperature is too low, then your coffee will taste underdeveloped and sour because the solubles are not being extracted efficiently.
• If your water temperature is too high, then your coffee will taste burnt or bitter because the grounds are being scalded.

FAQ

Can I make “regular” coffee in a Chemex?

Absolutely. The Chemex is designed to brew a clean, drip-style coffee, which is often what people mean by “regular” coffee. It’s an excellent way to make a clear, bright cup without sediment.

What is the best coffee-to-water ratio for a Chemex?

A good starting point is a ratio between 1:15 and 1:17. For example, 30 grams of coffee to 450-510 grams of water. You can adjust this to your preference for a stronger or weaker brew.

How coarse should my coffee grind be for a Chemex?

You should aim for a medium-coarse grind, similar to sea salt. If your grind is too fine, it can clog the filter and lead to over-extraction. If it’s too coarse, your coffee will be weak and sour.

How hot should the water be for brewing?

The ideal water temperature for Chemex brewing is between 195°F and 205°F (90.5°C to 96°C). Water that is too cool will under-extract, and water that is too hot can scald the coffee grounds.

Why does my Chemex coffee taste bitter?

Bitter coffee often results from over-extraction. This can be caused by water that’s too hot, a grind that’s too fine, or brewing for too long. Adjusting your grind size and water temperature can help.

Why does my Chemex coffee taste sour?

Sour coffee is usually a sign of under-extraction. This can happen if your water isn’t hot enough, your grind is too coarse, or you didn’t use enough coffee. Try a finer grind or hotter water.

How often should I clean my Chemex?

You should wash your Chemex carafe with soap and warm water after every use to remove coffee oils. Periodically, you should descale it to remove mineral buildup, especially if you have hard water.

What kind of filters does a Chemex use?

Chemex brewers use proprietary, thick paper filters designed specifically for the brewer. They are available in square and circular shapes and are crucial for achieving the clean taste the Chemex is known for.

What this page does NOT cover (and where to go next)

• Specific coffee bean recommendations or roast profiles.
• Advanced techniques like specific pour patterns for competitive brewing.
• Detailed guides on troubleshooting specific machine issues (as the Chemex is manual).

To learn more, consider exploring resources on coffee science, different brewing variables, and the nuances of coffee tasting notes.