Hi, If a recipe calls for tartaric acid is it OK to substitute cream of tartar? Thanks, Gillian
Unfortunately tartaric acid and cream of tartar are not quite the same thing, though cream of tartar is made from tartaric acid. Tartaric acid occurs naturally in some fruits such as grapes and bananas but most tartaric acid is collected from the wine making process (where it forms naturally) or synthesized in factories. As its name suggests it is quite sour and was used to add sharpness to soft drinks (sodas), such as lemonade, or to reduce oxidization in food.
Cream of tartar is made by combining tartaric acid with potassium hydroxide. This partially neutralizes the tartaric acid, so cream of tartar is less acidic than tartaric acid.
If the tartaric acid is used in baking or added to egg whites before whisking into meringues then it should be possible to use cream of tartar in roughly double the quantities of the tartaric acid, though we have not tested this. However we would not recommend using cream of tartar as a substitute in any other recipe.