酒石酸, C₄H₆O₆,是一种α-羧酸, 双质子酸，存在于多种植物中，如葡萄，香蕉和罗望子，也是葡萄酒中主要的有机酸之一。通常与小苏打组合以充当面粉膨松剂。作为食品中添加的抗氧化剂，可以使食物具有酸味。酒石酸盐它是琥珀酸的二羟基衍生物。大约在公元800年，由炼金术士贾比尔首次从酒石酸钾分离出酒石酸。现代化的工艺是由瑞典化学家卡尔·威廉·舍勒于1769年开发的。

化学手性的发现中酒石酸发挥了重要的作用。酒石酸具有两个相互对称的手性碳，具有三种旋光异构体：左旋L-酒石酸、右旋D-酒石酸、内消旋酒石酸，其中右旋体最为常见。

Tartaric acid is a white crystalline organic acid that occurs naturally in many plants, most notably in grapes. Its salt, potassium bitartrate, commonly known as cream of tartar, develops naturally in the process of winemaking. It is commonly mixed with sodium bicarbonate and is sold as baking powder used as a leavening agent in food preparation. The acid itself is added to foods as an antioxidant and to impart its distinctive sour taste.