Tartaric acid occurs in nature as a crystalline organic acid and as salts when combined with a base. As an organic acid, it is found in fruits and as a by-product of the winemaking process. It is used as a flavouring and stabiliser in the food and beverage industries, as well as in manufacturing processes. It also has medicinal, photographic and leather curing applications.
Food and Beverages
Tartaric acid (C4H6O6) is an organic acid that occurs naturally in fruits like bananas, tamarind and grapes. Processed tartaric acid is made by reducing the sediment or sludge known as "wine lees" that is left behind in wine fermentation vats after wine is bottled. It is used as a food additive and flavour enhancer in candies, bakery goods, jellies, jams, ice cream and soft drinks and as an emulsifier in bakery goods. It is an ingredient in cream of tartar and baking powder, and is used as a coagulant in the production of mascarpone cheese.
Tartaric acid also occurs in nature as salts when combined with a base, most often in the form of calcium, potassium and sodium tartrates. These salt varieties are used in manufacturing dyes for the textile industry, in leather tanning, in the manufacture of lacquer paints, in the silvering used for mirrors and in the ink used to produce blueprints. Tartaric acid also is used to manufacture gels that are used in film processing. In the building industry, it is used as a retardant in the handling of cement, gypsum and plaster.
Medical and Pharmaceutical
Tartaric acid is used as a medicine as a laxative and as an emetic that forces people to vomit after they have ingested a toxic substance. It is also used as a binder in foaming tablets and medicinal powders, as well as in solutions that measure blood-glucose levels.
In his 2002 book "Biological Treatments for Autism and PDD," William Shaw cited his research into the presence of toxic elevated values of tartaric acid (yeast) in the urine of children suffering from autism. He posited that tartaric acid was the yeast source and that anti-fungal therapy would reduce some of the children's symptoms. Shaw reported that after some of the children were treated with anti-fungal drugs, their tartaric acid values (levels) were near normal and their symptoms were reduced. These included decreased hyperactivity, more eye contact and vocalisation and reduced stereotypical autistic behaviours, like spinning objects.