Buttermilk

Traditional buttermilk is the thin, slightly tangy liquid that naturally remains after churning butter out of cultured cream. However, the buttermilk sold in modern supermarkets is almost always "cultured buttermilk," which is made by adding lactic acid bacteria to low-fat milk to simulate the traditional flavor and thickness. Cultured buttermilk is thicker and more acidic than the traditional leftover byproduct.

If a recipe calls for buttermilk, you should not substitute regular milk directly, as the buttermilk's acidity is required to activate the baking soda and create a rise in baked goods. To make a substitute, you can add one tablespoon of white vinegar or lemon juice to a cup of regular milk and let it sit for 5 to 10 minutes. This mixture will curdle slightly and mimic the acidic reaction needed for your recipe.

Buttermilk is widely used to marinate chicken, especially in Southern American cuisine, because its mild acidity helps to break down the proteins in the meat. This process tenderizes the chicken, keeping it juicy and moist while also helping the seasoned flour coating adhere better to the skin. The result is a highly flavorful, tender piece of fried chicken with a crispy crust.

No, despite its name, commercial cultured buttermilk contains no butter and is generally quite low in fat. The name originates from the historical process where it was the liquid left behind after the butter had already been extracted from the cream. Modern buttermilk is essentially a fermented dairy product, closer to a drinkable yogurt than a fatty butter product.