It is used to stabilize beaten egg whites in angel food cake and meringues. To replace 1 teaspoon of baking powder mix 1/2 teaspoon Cream of Tartar to 1/4 teaspoon each of baking soda & corn starch. The potassium salt of tartaric acid used to stabilized egg whites in baking. The chemical names are potassium acid tartrate, potassium hydrogen tartrate, and potassium bitartrate.
Used in curry mix, marinades, stews, and for dredge/breading mix of chicken/pork chops.