Total acidity is the measure of all the acids in a wine, including both the fixed and volatile acids. This is typically measured in the laboratory through a system called titration; portions of alkali are added to precise amounts of grape juice or wine until the alkali equals the acids in the test. What is really important here is that, when grape juice is converted into wine, it loses some of its acidity through cold stabilization and/or malolactic fermentation. So for winemakers to create a wine of a total acidity level they desire, they must first be aware of that measurement before they begin to ferment the juice, and then take the anticipated loss of acidity in account for the finished wine—lest they create a wine that is out of balance.