Water Recipe for Best French Press Coffee

Key Points:

  • Ideal water hardness for French press coffee is 50-100 ppm.
  • Use water with a balanced mineral profile (magnesium and calcium) for optimal extraction.
  • Avoid using water that is too soft (low in minerals) or too hard (high in minerals).

The best water recipe for French press coffee strikes a balance between hardness and softness to optimize flavor extraction while avoiding over-extraction or flatness. The right water enhances the coffee's natural flavors, balances acidity, and brings out sweetness, without bitterness.

1. Water Hardness: 50-100 ppm

  • The ideal total dissolved solids (TDS) for French press water is between 50-100 ppm (parts per million). This ensures that the water has enough minerals to aid extraction but not so much that it leads to over-extraction and bitterness.
    • Calcium and magnesium are the key minerals that aid in the extraction of coffee compounds. Magnesium is especially important because it enhances coffee flavor, while calcium contributes to body and balance.

2. Magnesium and Calcium Balance

  • For optimal flavor development, a good ratio is about 10-15 mg/L of magnesium and 20-40 mg/L of calcium. This provides enough mineral content to draw out the coffee’s aromatic compounds while maintaining smoothness and clarity.

3. Low Alkalinity

  • Water with low alkalinity (20-40 ppm bicarbonate) is ideal because it allows the coffee's natural acidity to shine without muting it. High alkalinity water (common in hard water areas) can neutralize acidity, leading to a flat and lifeless brew.

4. Water Recipe Example

If you don’t have access to ideal tap water, you can create your own using the following recipe:

Ingredients:

  • Distilled or Reverse Osmosis (RO) water: 1 liter (starting base for adjusting mineral content).
  • Epsom salt (Magnesium sulfate): Adds magnesium for flavor clarity.
  • Baking soda (Sodium bicarbonate): Adds alkalinity but should be used sparingly to avoid flatness.
  • Calcium chloride: Adds calcium for body and balance.

Recipe:

  1. Start with 1 liter of distilled or RO water.
  2. Add 0.5 grams of Epsom salt (Magnesium sulfate) to achieve around 15 mg/L of magnesium.
  3. Add 0.25 grams of Calcium chloride to add around 25 mg/L of calcium.
  4. Optionally, add a tiny pinch of baking soda (just a few grains) if you want to slightly increase alkalinity, but do not exceed 10 mg/L.

5. Third Wave Water

Alternatively, you can use pre-formulated water additives like Third Wave Water. These are specifically designed for brewing coffee and provide the perfect balance of magnesium, calcium, and alkalinity. Simply mix the sachets with distilled water for a precise mineral balance.

Conclusion

The best water for French press coffee is one that has balanced mineral content, low alkalinity, and moderate hardness, with TDS between 50-100 ppm. By controlling these elements, you can significantly improve the taste, clarity, and body of your French press brew.