Sodium bicarbonate

When adjusting water chemistry with sodium hydrogen carbonate (NaHCO₃), the amount needed depends on:

1. Your original water profile

2. The desired final pH of the mash (typically 5.2-5.6)

3. The beer style (dark beers often require more adjustment than light beers)

4. The amount and type of malt used

Typical dosage for 25 litres of water:

• 1 gram of sodium hydrogen carbonate per 25 litres of water Will add approx:

  • 27 ppm sodium (Na⁺)

  • 73 ppm bicarbonate (HCO₃-)

This will raise the mash pH slightly, which is especially useful when using very dark malts.

Example - Dark beer (stout or porter):

If you have soft water with low alkalinity (e.g. RO or rainwater) and you want to brew a dark beer with a high content of roasted malts, you can add 2-3 grams of sodium hydrogen carbonate per 25 litres of liquid water. This will help neutralise the acidity that dark malts contribute and ensure a suitable mash pH.

Caution:

• Don't add too much - over 5 grams per 25 litres can give a salty or soda-like taste.

• Use pH measurement as a guide. Start low and measure during mashing.

• If necessary, use a water treatment tool such as Bru'n Water or Brewer's Friend for accurate calculations.