Plain unsweetened kefir can serve as a substitute for buttermilk. Kefir is a fermented milk drink similar to a thin yogurt, made from kefir grains and milk which results in a tart, slightly fizzy beverage.
Its consistency is generally more liquid than buttermilk.
In recipes, kefir can replace buttermilk at a 1:1 ratio. For instance, if a recipe calls for 1 cup of buttermilk, you can use 1 cup of kefir.
It provides the acidity and tanginess that buttermilk would contribute to a recipe, which is essential for both flavor and chemical reaction, especially in baking where it interacts with baking soda to help the product rise.
The probiotic nature of kefir, due to its fermentation process, also offers additional digestive benefits, though these are largely lost during baking due to the heat.
However, because kefir is usually thinner than buttermilk, it might affect the texture of some recipes, particularly those where the thickness of buttermilk is essential for the desired final product.
This can potentially be adjusted by reducing other liquid ingredients slightly or by adding thickeners if necessary.