Buttermilk

Orignially buttermilk was the liquid left after butter was churned but today it is produced by adding special bacteria to nonfat or lowfat milk, giving it a slightly thickened texture and tangy flavor. Buttermilk is also available in powdered form which is very convenient for use in baked goods and batters.Read more about buttermilk >>

These subs. are good for baking and batters - not for uncooked foods like dressings.
For 1 cup buttermilk select one:
1 cup milk + 1 tablespoon lemon juice
1 cup milk + 1 tablespoon white vinegar
1 cup milk + 1 teaspoon cream of tartar