How to substitute for buttermilk

You cast your eyes over the list of ingredients in this new recipe you’re trying and lo and behold, there’s that darned buttermilk. You don’t have any buttermilk; in fact, you never buy buttermilk because there are very few baking recipes that use it and who wants an almost-full quart of buttermilk sitting in the back of the fridge making you feel guilty for contributing to food waste? So you sigh and turn to another recipe: one without buttermilk. But is there an easy substitute for buttermilk — something you already have in your kitchen?

First, let’s clarify what buttermilk is, exactly. Traditional buttermilk is the thin, watery liquid left over after cream is churned into butter. It’s not commonly available in grocery stores — and hasn't been since the 1920s, when it was supplanted by our present-day cultured buttermilk, low-fat or skim milk that’s been inoculated with milk-friendly bacteria to thicken it and make it sour.

Many of the recipes you see calling for buttermilk are classics: pancakes, biscuits, cake. Buttermilk was a readily available ingredient (and one not to be wasted) back when butter-making was a common household task. Prized for its leavening ability when paired with baking soda, it was the basis of many a light and fluffy pancake and cloud-like biscuit.

Today, buttermilk isn’t a pantry staple for most of us, but rather something you purchase for one particular recipe. Which brings us back to where we started: If you don’t want to buy a quart of buttermilk, what can you substitute?

Here are the most common suggestions:

• 1 tablespoon vinegar or lemon juice mixed into 1 cup of milk. Let the milk stand for 10 to 15 minutes, until it thickens very slightly and curdles.
• 1 3/4 teaspoons cream of tartar mixed with 1 cup of milk. Shake until the cream of tartar dissolves.
• Sour cream thinned with milk or water to the consistency of heavy cream.
• Plain unsweetened kefir.
• Yogurt thinned with milk or water to the consistency of heavy cream.

Best substitute for buttermilk: The tests

I decided to try several of these options in pancakes, biscuits, and a favorite buttermilk cake. 

First off, I eliminate kefir (not a pantry staple) and sour cream (similar enough to Greek yogurt).

I also cross standard yogurt off the list, because how easy is it to find “un-Greek” yogurt these days? Scanning the shelves in my local supermarket I find one small section of plain yogurt — in quart-sized containers. Heck, I might as well buy a quart of buttermilk as plain yogurt.

But thick Greek yogurt — it’s ubiquitous. And many of you probably keep a container or two in your fridge most of the time for snacking, mixing with granola, or whipping up a smoothie.

From previous pancake experiments in our test kitchen, I know that Greek yogurt mixed 1:2 with 1% or skim milk (one part yogurt, two parts milk) yields the best results. It's also an easy ratio: mix one small container (5.3 ounces) of Greek yogurt with 1 1/3 cups of milk to yield 2 cups of buttermilk substitute.

So I test milk with vinegar, milk with cream of tartar, and thinned Greek yogurt against the control: buttermilk. While I'm at it, I take a step back and decide to test the easiest substitution of all: plain 1% milk in place of buttermilk.

Let's look at the results.

What to substitute for buttermilk in biscuits

My first test, Baking Powder Biscuits, turns out to be a harbinger of things to come: all of the biscuits rise nicely and brown well. On sampling, their texture is the same — but the flavor of the buttermilk biscuits is best, a slight tang mixed with a hint of sweetness (is it the milk solids?). The yogurt biscuits taste almost as good. The vinegar and cream of tartar biscuits seem to lack depth of flavor, while the plain milk biscuit simply tastes flat.

Winner: Buttermilk
Runner-up: Greek yogurt mixed with milk

What to substitute for buttermilk in pancakes

Substituting anything for buttermilk in Buttermilk Pancakes certainly belies the recipe's name. But aside from that, I notice results very similar to the biscuit experiment. The texture and browning of each of the pancake batches are similar — with the exception of the plain milk pancake, which rises less. But when it comes to flavor, the buttermilk and yogurt pancakes are neck and neck, with the others lagging slightly behind.

Winner: Buttermilk and Greek yogurt mixed with milk (tie)

What to substitute for buttermilk in cake

This Farmhouse Buttermilk Cake recipe is an old favorite of mine. The photo above doesn't do it justice; I was out of pecans so substituted walnuts, and then didn't chop them finely enough (rush, rush!). But this tender, golden cake, topped with its buttery, nut-laden syrup, is a true crowd-pleaser.

Compared to biscuits and pancakes, with their simple ingredients, this cake is complex: brown sugar, butter, vanilla, and nuts all contribute to the flavor profile. And because of that, the subtle, layered flavor of buttermilk in the cake is lost; you'll do just as well using any of the substitutes.

That is, with the exception of plain 1% milk. This old-fashioned cake is leavened with baking soda. Using plain milk, which lacks buttermilk's acidity, results in a darker-colored, denser cake.

Winner: All suggested options except plain milk

How to substitute for buttermilk: Your takeaways

• The shorter a recipe's ingredient list, the less successful a buttermilk substitute will be. Buttermilk's flavor is tangy but not strong, and its rich under notes are subtle. When paired with just a few simple ingredients (e.g. flour, perhaps an egg, fat), buttermilk's flavor is starkly apparent. When set against other competing flavors, though, buttermilk tends to disappear. So in cakes or quick breads, with their sugar and spice, buttermilk substitutes work well — though don't opt for substituting plain milk in recipes using baking soda.
• Building on that fact, the less buttermilk in a recipe, the easier it is to use a substitute. If your chocolate cake recipe calls for 1/4 cup buttermilk, don't sweat it; even using plain milk will probably be OK.
• In simple recipes where buttermilk's flavor may be front and center, your top substitute will be Greek yogurt mixed with milk. With its similar fermented, nuanced flavor, thinned yogurt steps in nicely for buttermilk.
• In recipes where buttermilk is the main ingredient (e.g., homemade buttermilk ranch dressing, cold buttermilk soup), it's best to spring for cultured buttermilk.

One last note about liquid buttermilk: If you buy a quart and don't use it up, you can always freeze it in 1/2-cup (or your preferred size) portions. It'll probably separate when you thaw it, but no worries; it's fine to use.

Now, what about dried buttermilk powder? I didn't include it in my testing results as, again, it's not an ingredient you'd likely stock in your pantry on a regular basis (unless you're an inveterate buttermilk baker). But it works as well as the "soured milk" options (milk + vinegar or cream of tartar). While lacking real buttermilk's rich flavor, it does react well with leaveners and help provide a good rise.

Speaking of biscuits, my fellow blogger Kye did a comprehensive test of different fat/liquid combinations in biscuits. (Spoiler alert: Her favorite biscuits include butter and buttermilk). For Kye's complete results, see Fats and liquids in biscuits: choosing your favorite texture.

Cover photo by Jennifer Bakos