Coffee to Water Ratio for Chemex: Learn the Amount of Coffee to Water in Chemex
Brewing coffee with a Chemex is a delicate and rewarding process that results in a clean, flavorful cup. One of the key factors in perfecting your Chemex brew is nailing the right coffee-to-water ratio. This guide will walk you through everything you need to know about the best ratio, why it matters, and how to customize it to fit your preferences.
What is the Chemex Coffee Maker?
Before diving into the coffee-to-water ratio, let's briefly introduce the Chemex for those who may be new to this brewing method. The Chemex is an iconic pour-over coffee maker, designed with a sleek glass hourglass shape and thick paper filters.
Invented by Peter Schlumbohm in 1941, the Chemex provides a balanced, bright cup by filtering out oils and fine particles. Coffee brewed in a Chemex tends to have a lighter body and a cleaner finish compared to other methods.
Why Coffee to Water Ratio Matters
The coffee-to-water ratio is one of the most critical elements of any brewing process, particularly in a Chemex. This ratio determines the extraction of flavours from the coffee grounds. Too much coffee and too little water can lead to an overly bitter, strong brew, while too much water and too little coffee can result in a weak and underwhelming cup. A balanced coffee-to-water ratio ensures optimal extraction, allowing you to enjoy the full spectrum of flavours from your beans whether you prefer fruity, floral, or chocolatey notes.
The Ideal Chemex Coffee-to-Water Ratio
The most widely accepted coffee-to-water ratio for Chemex brewing is 1:15 to 1:17. This means:
- For every 1 gram of coffee, use 15 to 17 grams (or millilitres) of water.
In simpler terms, if you're making an 8-cup Chemex, you might use:
- 40 grams of coffee to 600 millilitres of water (1:15 ratio)
- 40 grams of coffee to 680 millilitres of water (1:17 ratio)
These ratios allow you to experiment within a range, depending on how strong you like your coffee. The 1:15 ratio will yield a stronger brew, while the 1:17 ratio will result in a slightly lighter cup.
How to Calculate the Coffee-to-Water Ratio for Chemex
Understanding the exact weight of coffee and water for your Chemex is easy if you have a kitchen scale. Here's how you can break it down:
Decide on the batch size: Determine how many cups of coffee you want to brew. A standard cup is approximately 5-6 ounces (150-180 millilitres).
Weigh your coffee: For a medium to large batch, a good starting point is to use 40 grams of coffee for 600 to 680 millilitres of water.
Adjust for taste: Depending on your preference for a stronger or milder cup, adjust the water or coffee slightly. For example, if you prefer a stronger coffee, stick closer to a 1:15 ratio. For a lighter brew, go for a 1:17 ratio.
The Role of Grind Size in the Chemex Brew
Beyond the coffee-to-water ratio, grind size is another essential variable that impacts the quality of your Chemex brew. For the Chemex, a medium-coarse grind is ideal. It should resemble sea salt in texture, which allows for the right flow rate during the brewing process.
If the grind is too fine, the water will flow too slowly, leading to over-extraction, which can cause bitterness. If the grind is too coarse, the water will flow too quickly, resulting in under-extraction and a weak cup.
Brewing Technique for Chemex: Step-by-Step
Once you’ve measured your coffee and water, follow these steps to brew the perfect Chemex coffee:
- Prepare the Chemex: Place a Chemex filter inside the top of the brewer and rinse it with hot water. This removes any papery taste and warms the glass.
- Add your coffee grounds: After discarding the rinse water, add the measured coffee grounds to the filter.
- Begin the bloom: Start by pouring a small amount of hot water (just off the boil, around 200°F or 93°C) over the coffee grounds. Pour just enough to saturate the grounds and let it sit for about 30 to 45 seconds. This step is called the "bloom" and allows the coffee to degas, resulting in better extraction.
- Pour in the remaining water: Slowly pour the rest of your water in a circular motion, starting from the center and moving outward, then back to the center. Try to keep a steady flow to avoid disturbing the grounds too much.
- Let the coffee drain: Once you’ve poured all the water, let the coffee drip through the filter completely. This should take about 4 to 5 minutes. If it’s going too fast or too slow, you may need to adjust your grind size next time.
Serve and enjoy: Once brewing is complete, remove the filter and pour your coffee into a cup or carafe.
Customizing the Ratio for Personal Taste
While the 1:15 to 1:17 ratio is a great starting point, there is room to adjust based on your personal preference:
For a stronger cup: Try a 1:14 ratio by increasing the coffee grounds while keeping the water amount constant. This will make the brew more concentrated.
For a lighter cup: Go with a 1:18 ratio by adding a little more water relative to your coffee amount. This is perfect if you enjoy a milder coffee flavour.
Experimenting with different ratios will help you find the ideal balance for your taste buds. Don’t be afraid to try small adjustments until you find the perfect brew.
Water Quality and Temperature
Water quality plays a significant role in the outcome of your coffee. Use filtered water whenever possible to avoid any off-flavours from minerals or chemicals present in tap water.
The ideal brewing temperature is between 195°F and 205°F (90°C to 96°C). If you don't have a thermometer, let your water sit for about 30 seconds after boiling to reach the right temperature.
Conclusion
The coffee-to-water ratio for Chemex is a vital part of crafting the perfect cup. Sticking to a 1:15 to 1:17 ratio will generally produce excellent results, but the fun part of brewing with a Chemex is adjusting to suit your own taste. Remember to pair the right ratio with the appropriate grind size, water temperature, and brewing time, and you'll be able to enjoy consistently great coffee every time.
Whether you’re new to Chemex brewing or an experienced home barista, mastering the coffee-to-water ratio will elevate your coffee-making game and allow you to fully enjoy the unique flavours of your favourite beans.
Frequently Asked Questions About Chemex Coffee-to-Water Ratios
How much coffee do I need for a 6-cup Chemex?
For a 6-cup Chemex, using 30 to 36 grams of coffee with around 500 to 600 millilitres of water will result in a well-balanced brew.
Can I use a 1:20 ratio in a Chemex?
While you can try a 1:20 ratio, this will produce a very light and diluted cup of coffee. It might work for people who enjoy a more tea-like brew, but it's generally not recommended for Chemex.
Why is my Chemex coffee weak?
If your Chemex coffee is weak, it could be due to an incorrect coffee-to-water ratio or a grind that is too coarse. Double-check both factors and make adjustments accordingly.
How do I adjust the coffee-to-water ratio if I'm making a single cup of Chemex coffee?
To brew a single cup of coffee (around 10-12 ounces or 300-350 millilitres) using the Chemex, a good starting point is to use around 20-24 grams of coffee with 300-350 millilitres of water. Stick to the same 1:15 to 1:17 ratio and adjust slightly depending on your taste preference. If you prefer a stronger cup, use closer to 20 grams of coffee for every 300 millilitres of water.
Why does my Chemex coffee taste bitter even when I use the recommended coffee-to-water ratio?
If your coffee tastes bitter, it could be due to over-extraction, which happens when the coffee grounds are in contact with water for too long. This could be caused by a grind that is too fine or by brewing for too long. Try using a coarser grind or reducing the brewing time to around 4 minutes, while keeping the coffee-to-water ratio the same.
Can I use pre-ground coffee for my Chemex, and how does it affect the ratio?
While freshly ground coffee is recommended for the best flavour, you can use pre-ground coffee for your Chemex. However, make sure that the grind size is suitable - medium-coarse, similar to sea salt. The coffee-to-water ratio remains the same at 1:15 to 1:17, but keep in mind that pre-ground coffee may lose some freshness, affecting the final flavour of your brew.
