What it is
Tartaric Acid is an organic alpha hydroxy acid that occurs naturally in grapes and several other fruits. In formulations it is mainly used to adjust and buffer pH and to help bind metal ions, and at appropriate levels and pH it can contribute mild exfoliating activity. In sunscreens it most often serves a supporting role to keep the product at a stable, skin-appropriate pH.
Safety & warnings
At the low levels and buffered pH used in most cosmetics, tartaric acid is well tolerated. As an alpha hydroxy acid it can cause stinging or irritation at higher concentrations or low pH, and AHAs in general may increase skin sensitivity to the sun.
Origin & sourcing
Can be naturally derived or synthetic. The natural form is a byproduct of winemaking, obtained from grapes, while it can also be produced synthetically; the form supplied to cosmetics may be either depending on grade.
History
Tartaric acid was first isolated from tartar deposits in wine casks in the late 18th century and has since become a common ingredient in food and personal care products.
Questions everyone asks
What does tartaric acid do in a formula?
It is most often used to adjust and buffer pH and to chelate metal ions, and at suitable levels it can offer mild exfoliation.
Is tartaric acid an AHA?
Yes, it is an alpha hydroxy acid naturally found in grapes, though in many products it functions mainly as a pH adjuster rather than an exfoliant.