I made a recipe for whole grain scones, back in March, and realized that there is a surprisingly amount of mystery about buttermilk. The mystery is not unreasonable, as traditional buttermilk and commercial butter are different, not to mention all the possible culinary equivalents. Nutritionally, the fat and probiotic of buttermilk varies with all thsoe possibilities.

Traditional buttermilk: Buttermilk was classically the skim milk left after making butter. However, most butter was made from raw milk that was allowed to separate at room temperature, so the milk was cultured by lactic acid bacteria naturally present. It was acidic, contains probiotics, and was low in fat.

Traditional cultured buttermilk: Cultured buttermilk may be simply cultured milk. As such, it can be whole milk, part-skim, or skim milk. The texture thickens, much as yogurt’s texture thickens, as the bacteria create an acidic environment, curdling the proteins. Truly traditional buttermilk would be made with raw milk, but pastuerized milk can be used with a starter. Cultured buttermilk does contain probiotics, although the specific cultures vary regionally.

Commercial cultured buttermilk: Commercial buttermilks are cultured milk, as above, made from pastuerized and homogenized milk. Typically, in the US, 1 1/2% milk is used. Often, there are thickeners such as carregeenan. It does have live cultures, and is acidic. Commercial buttermilks contain probiotics, and are low fat. Sometimes, when substituting homemade cultured buttermilk for commercial buttermilk in gluten-free baking recipes, I find it helpful to add a 1/2-1 teaspoon of ground flax to compensate for the thickeners in commercial buttermilk.

Acidified buttermilk substitutes: Culinarily, the most important aspect of buttermilk is the acid. Usually, in baking, recipes calling for buttermilk use baking soda, which needs an acid to react with. “Instant” buttermilk for baking can be made by mixing 1 T lemon juice or vinegar with 1 c milk, stirring well, and allowing it to sit for 5-10 minutes. A mild vinegar is probably your best bet– cider vinegar is popular, rice vinegar works well, and white wine vinegar is my favorite. I suggest avoiding balsamic, sherry, or red wine vinegar. Acidified buttermilk could also be used for dressings, but I’d suggest using a cultured version for better flavor. The fat content of the milk will depend on what you started with, and it does not contain probiotics.

Non-dairy buttermilk: Vegan or non-dairy buttermilks can be made by adding 1 T of lemon juice or a mild-flavored vinegar to 1 c of faux milk. In recipes for dressings or casseroles where the thicker creaminess matters, you may find it easier to substitute a plain unflavored vegan yogurt made from soy, coconut, nut, or other milk. Buttermilk starters could also be added to your favorite milk, but success could be pretty variable depending on whether your milk contains enough of the correct types of sugars to support the culture. The fat content of the milk will depend on what you started with, and it does not contain probiotics.

What is buttermilk used for? It’s commonly used in soda bread, pancakes, biscuits, muffins, cornbread, mashed potatoes, creamy salad dressings, and cheese. Pretty much anything baked– cakes, waffles, rolls, bread, brownies, pie crust– can be made with buttermilk. Mix it up with yogurt or mayo for a tuna or pasta salad, and the oh-so-terrible but popular ranch dressing ought to contain buttermilk. At last resort, you can freeze it for future bakingprojects.

Goat’s Milk Cultured Buttermilk

Using the sterilized equipment will help prevent contamination by other bacteria strains, so it is especially important if you intend to continually re-culture your buttermilk. Any amount of buttermilk can be made as long as the 3:1 ratio of milk:starter is maintained. Obviously, for 100% goat buttermilk, you would need to start with a cultured goat’s milk rather than a commercial cow’s milk.

1 c cultured buttermilk (commercial or homemade)
3 c goat milk

Mix the container of buttermilk before measuring it (shake or use a sterilized fork or whisk) into a sterilized jar with the milk. Bring the cultured buttermilk and the milk to about 85 degrees F (lukewarm, or use a sterilized thermometer). I typically do this by placing the jar of milk in a warm water bath. Be very careful to not overheat the buttermilk, or you might kill your good bacteria. Cap it with a sterilized lid. Mix together the milk and buttermilk in the jar by tightening the jar and shaking. Leave the jar in a warm place (ideally, 75 to 85 degrees F) for approximately 24 hours. It should smell strongly of buttermilk. Shake, and refrigerate.

This recipe can be used for raw or pasteurized milk. As I noted before, I strongly recommend pasteurized milk unless you have complete control over your milk supply and are very careful. It is particularly important for anyone with a compromised immune system to avoid raw milk.