pH in winemaking

For the non-scientist pH is a some what difficult concept to come to terms with, being an indication of acidity and yet not the same as Total Acidity and whose figures are the opposite way around. With TA the more acid, the higher the figure, but with pH, the more acid the lower the figure.

pH in winemaking is very important to keep aware of. pH controls the functions that affect the color, taste, and keeping the wine’s qualities, especially in relation to SO2 (potassium metabisulfite).

The pH scale is from 0 to 14, 0=sulfuric acid (very acidic), with 7 being neutral (as in pure water) and 14 being caustic soda (very alkaline)

Most wines fall between pH 2.8 to 4.0, a high acid Muscadet of pH2.8 to a soft warm climate Australian Merlot of pH 3.5 Although the range of pH found in wine is small, differences of 0.2 are important.

With pH, the more acid in the wine the lower the number (pH3.0 is more acidic than pH3.4)

With TA(total acidity) the more acid in the wine the higher the numberĀ  .75% TA has more acid than .65%TA)

When you want to increase your TA, you add acid such as Tartaric or Acid blend. If you want to lower your acidity you add water.

When you want to lower your pH you add Potassium Carbonate in the primary fermenter, if you are trying to lower your pH after primary fermentation then use Calcium Carbonate.

To reduce titratable acidity by .1% add 1/2 tsp. per gallon of must before cold stabilization. Will not give wine a chalky taste.