Uses: Chalk (AKA calcium carbonate) is used for acid reductions in wine and hardening water for beer. Use in acid reductions must be considered a last choice, as other materials produce better results with less off flavour. Consult a good winemaking or beer making book for possible usage. 5 mL (one teaspoon) = approximately 2.1 grams.
Hint: Excess of calcium carbonate will give wine a “chalky” flavour.