Naturally occurred is predominantly L-form of tartaric acid whereas its D-form and the relevant racemic  mixture can be artificially synthesized. Generally, artificial acidification of wine with tartaric acid is allowed  by OIV, but only pure L-form must be used for this purpose. Thus the analysis of tartaric acid isomers  either in food additives or directly in wine can be an important parameter in clarifying any deviations in  wine production. Analysis of isomers of malic acid is also within the necessary oenological procedures stated in OIV recommendations.