Buttermilk is used to give pancakes a light and fluffy texture, but buttermilk, plain yogurt, sour cream and cream of tartar are three commonly used substitutions. There is no single ingredient that is considered the best as a substitute for buttermilk.
Buttermilk provides acidity, which interacts with baking soda to help lighten and expand pancake batter. All of the substitutes commonly used, when combined with regular unspoiled milk, bring an acidic component to the batter. In addition to plain yogurt, sour cream and cream of tartor, other popular alternatives include lemon juice and vinegar. Another way to add acidity without buttermilk is to substitute baking powder for baking soda.