L(+)-Tartaric acid (87-69-4)

 L(+)-Tartaric acid , its cas register number is 87-69-4. L(+)-Tartaric acid , its cas register number is 87-69-4. It also can be called (+)-Tartaric acid ; L(+)-Dihydroxysuccinic acid ; and Natural tartaric acid . L(+)-Tartaric acid (CAS NO.87-69-4) 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.