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How to Substitute Cultured Dairy Products

Everybody does it (even though they shouldn't). Here are some tips for doing it well.

A Better Sub for Buttermilk: Yogurt + Water

Many recipes for baked goods—pancakes, biscuits, and cakes in particular—call for buttermilk: Its acid reacts with baking soda to create a leavening effect, its viscosity gives batter a specific consistency, and its mild sourness contributes flavor. A common replacement for buttermilk is clabbered milk, which is milk that has been mixed with a small amount of lemon juice or vinegar. The acid provides tang and causes the proteins to aggregate, but it doesn't give the liquid body.

But when we made drop biscuits and buttermilk pancakes using clabbered milk, the results were disappointing. Clabbered milk isn't nearly as thick as buttermilk. That meant that both baked goods spread more than they should have, slumping into squat, uneven shapes. Cakes containing clabbered milk fared better since the batter was corralled by the walls of the pan.

We had a hunch that yogurt, another acidic dairy product, might work well in all applications. It was too thick straight from the tub, but once we thinned it with water, it was more or less identical to buttermilk in acidity and consistency, and baked goods made with it were hard to distinguish from those made with the real thing.

Given its tangy flavor and buttermilk-like consistency, we also wondered if kefir, a fermented milk drink, could be used as a 1:1 sub for buttermilk in recipes. Because kefir typically contains more protein than buttermilk, pancakes and biscuits browned a touch faster but were perfectly acceptable (many tasters even preferred the extra browning and crispness of the kefir biscuits).

Moving forward, if we need to an alternative to buttermilk, we're going with thinned yogurt or kefir instead of clabbered milk.

To Replace: 1 cup buttermilk

  • ½ cup whole or low-fat yogurt + ½ cup water
  • ⅓ cup Greek yogurt + ⅔ cup water
  • 1 cup kefir

Sour Cream and Whole Milk Yogurt

These can be swapped for each other in equal measures in most baking recipes with good results, but since sour cream has more than four times the fat, expect cakes and muffins baked with yogurt to have a slightly drier texture. Flavored yogurts such as lemon or vanilla can be substituted for plain in recipes where the flavors won't clash.

To Replace: 1 cup sour cream

  • 1 cup whole milk yogurt

To Replace: 1 cup whole milk yogurt

  • 1 cup sour cream

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