Making homemade buttermilk takes less than 10 minutes and gives you a reliable substitute for baking when the store-bought version is not on hand. By curdling milk with an acid, you can create a creamy, tangy buttermilk substitute that works perfectly in pancakes, biscuits, and cookies.

Why Use Buttermilk in Recipes?

Buttermilk adds a pleasant tang to cakes, breads, and biscuits while also improving texture. Its acidity helps tenderize gluten, resulting in baked goods that are softer and more tender with better structure. It is especially important in recipes that use baking soda as the leavening agent. Baking soda requires an acidic ingredient, such as buttermilk or lemon juice, to activate properly and help baked goods rise. There are four great options for making your own homemade version, each using simple ingredients you likely already have on hand.

Vinegar Buttermilk

This is the most commonly used substitute and the closest in acidity to the traditional version. The vinegar reacts quickly with the milk proteins, creating light curdling and a thinner texture than store-bought. Expect a slightly tangy flavor with a consistency similar to whole milk. It will not be thick, but it provides the acidity needed to activate baking soda and tenderize baked goods.

Lemon Juice Buttermilk

Lemon juice works almost identically to vinegar but adds a subtle citrus note. The acidity level is similar, though the flavor can come through slightly more in delicate recipes. Expect a light curdling and mild thickening with a fresh, slightly brighter flavor. The texture stays fairly thin.

4 bowls of ingredients used to make homemade buttermilk.

Cream of Tartar Buttermilk

Cream of tartar provides acidity without adding liquid flavor, but it does not dissolve as easily. Whisking thoroughly is important to avoid graininess. Expect a very mild tang with slight thickening. This version curdles less visibly and can feel a bit chalky if not fully mixed.

Sour Cream Buttermilk

This version is richer and closer in texture to real buttermilk. Because sour cream already contains fat and tang, the result is thicker and creamier than the acid-only methods. Expect a smooth, pourable mixture with noticeable body and a gentle tang. It mimics cultured buttermilk more closely in both texture and mouthfeel.

Storage and Tips

Homemade substitutes are best used shortly after mixing, once they have rested for at least 10 minutes. They can be refrigerated for up to 24 hours, but separation is normal, especially with the vinegar and lemon juice versions. Simply stir before using.

Traditionally, buttermilk was the liquid left behind after churning butter. If you want to try that method, making homemade butter is another way to naturally end up with real buttermilk as a byproduct.