Tartaric acid may be most immediately recognizable to wine drinkers as the source of "wine diamonds", the small potassium bitartrate crystals that sometimes form spontaneously on the cork. These "tartrates" are harmless, despite sometimes being mistaken for broken glass, and are prevented in many wines through cold stabilization. The tartrates that remain on the inside of aging barrels were at one time a major industrial source of potassium bitartrate.

However, tartaric acid plays an important role chemically, lowering the pH of fermenting "must" to a level where many undesirable spoilage bacteria cannot live, and acting as a preservative after fermentation. In the mouth, tartaric acid provides some of the tartness in the wine, although citric and malic acids also play a role.

Used in many different applications due to its properties as: antioxidant, acidifier, flavor enhancer, stabilizer and sequestering agent.

Food industry

This is the main use of natural Tartaric Acid:
- As acidulant and natural preservative for jams and softdrinks.
- As emulsifier and preservative for bread-making.
- As effervescence for table waters.
- As leavening agent for desserts.

Oenology

Used to correct the acidity of the wine.

Pharmaceutical industry

Used as an excipient in the preparation of some medicines.

Building industry

Used in the gypsum and cement industries to retard drying and in the ceramic industry as fluidizer.

Cosmetic industry

Used as a basic component in some natural body creams.

Galvanoplastic industry

Used in preparation of polishing and cleaning solutions for electronic and galvanoplastic industry.

Textiles

Used as dyeing and printing agent.