Tartaric acid is a white, crystalline organic acid that occurs naturally in various fruits such as grapes, bananas, and tamarinds, and is widely used in the food and pharmaceutical industries as an acidulant, stabilizer, and antioxidant.
🏭⚗️ Production
Tartaric acid is industrially produced from natural sources like grape residues by isolating potassium bitartrate (cream of tartar) and converting it into tartaric acid through reactions with calcium hydroxide and sulfuric acid. It can also be synthesized chemically from maleic anhydride via oxidation and hydrolysis processes.
🔬 Properties
The chemical formula is C₄H₆O₆ with a molar mass of approximately 150.09 g/mol. It appears as a white, odorless, crystalline powder that is soluble in water and alcohol. Tartaric acid is optically active, with the naturally occurring form being L-(+)-tartaric acid. It has two stereocenters and several stereoisomers including meso and D- forms. Aqueous solutions are strongly acidic, with pKa₁ around 2.98 and pKa₂ about 4.34.
🧪 Applications
Tartaric acid is widely used in the food industry as an acidulant in baking powders, soft drinks, and candies, often in combination with sodium bicarbonate. In pharmaceuticals, it acts as a stabilizer in formulations and is used in effervescent tablets. It also serves as a complexing agent in metal plating, a chelating agent in analytical chemistry, and plays a role in the synthesis of emulsifiers and tartarate salts.
⚠️ Safety
Tartaric acid is generally recognized as safe (GRAS) when used in regulated amounts in food and pharmaceutical products. However, in concentrated form, it may cause irritation to the skin, eyes, and respiratory system. Protective gloves and goggles are recommended during handling, and it should be stored in a tightly sealed container in a cool, dry place away from incompatible substances like strong oxidizers and bases.
