Wine Acid Adjustment Calculator (Tartaric, Acid Blend, Deacidification)

How it works

Raise: grams = (target − current TA) × litres ÷ (TA contribution per g: tartaric 1.0, malic 1.12, citric 1.17). Lower: grams = (current − target) × 0.67 × litres for KHCO₃ or CaCO₃

Titratable acidity is what gives wine its freshness and, together with pH, governs microbial stability and how SO₂ behaves. Hot-climate grapes, most fruit wines and honey musts often need acid added — tartaric is the classic choice for grape wine because it is stable and does not get consumed by malolactic bacteria; blends with malic and citric suit fruit wines. Since TA is expressed as tartaric-acid equivalents, a gram per litre of tartaric raises TA by exactly one, while lighter acids raise it a little more. Lowering acid is harder: potassium bicarbonate acts quickly, calcium carbonate slowly, and both leave the wine tasting flatter, so drops beyond about 2 g/L are better achieved by blending or malolactic fermentation. Always add in stages and re-titrate.

Worked example

20 L at TA 5.0 g/L raised to 6.5 with tartaric acid: 1.5 g/L × 20 = 30 g, and pH should fall by roughly 0.15.

Frequently asked questions