Buttermilk is a rich, tangy, fermented milk product, with a flavour similar to yoghurt or sour cream. A popular ingredient in Southern cooking, it can be used to add a creamy, slightly tart flavour to baked goods, or as a marinade to tenderise meat. It also has probiotic benefits, can be used as a leavening agent, and has a longer shelf life than most dairy products.
If you’ve never tried buttermilk before, you might be expecting something high-fat, indulgent, and, well, buttery, but in fact buttermilk is a milk by-product, which means it’s basically everything that doesn’t end up as part of the butter.
Making butter involves churning heavy cream so the fat separates from the liquid, with the fat becoming butter, and the liquid becoming buttermilk. In the old days, it might take several milking sessions to collect enough cream for a decent amount of butter, and since there was no refrigeration, the older cream would ferment slightly as the naturally-occurring bacteria present in dairy products multiplied.
This natural fermentation process gave traditional buttermilk its distinctive tangy flavour, as well as several other useful characteristics. As a fermented product, buttermilk is quite acidic, which makes it a useful leavening agent. Combined with baking soda, acidic ingredients create a chemical reaction that produces carbon dioxide bubbles inside your dough or batter, making it airy and light.
Using buttermilk with soda can create the perfect, fluffy pancakes and waffles, and it also adds an irresistible creamy tang. Another important factor in the days before refrigeration was buttermilk’s relatively long shelf life. The lactic acid created as the buttermilk ferments inhibits the growth of dangerous bacteria, although it will take on a stronger flavour the older it gets, which is not to everyone’s taste.
These days we also know that buttermilk is a great source of beneficial bacterial cultures known as probiotics. These ‘friendly’ bacteria are the same as you might find in probiotic yoghurts, kefir, kombucha and other fermented foods, and can aid digestion and promote gut health. Like regular milk, it is particularly rich in calcium, but it tends to be lower in fat.
The production of modern buttermilk has moved out of the dairy and into the factory, and the method of production has changed too. Instead of churning cream and removing the fat to make butter, buttermilk is now made by inoculating milk with the same bacterial cultures found in old-fashioned buttermilk, and leaving it to ferment for 12 to 14 hours. This type of buttermilk is usually referred to as ‘cultured buttermilk’, and makes up most of the buttermilk available on the market today.
Because the fat doesn’t have to be removed from modern buttermilk, it can be made using any type of milk, from skimmed to full fat. Most are made using skimmed or semi-skimmed milk to mimic low-fat traditional buttermilk, but there are still some notable differences, with modern, cultured buttermilk tending to be thicker and tangier. It is also more acidic than old-fashioned buttermilk, which makes it an even better leavening agent than its ancestor.
Buttermilk is always undergoing fermentation, so it does have a tendency to separate, but if you give it a good shake, it should come back together. It is also important to remember not to heat it too quickly during cooking, as this will cause it to curdle. If you are including buttermilk in hot dishes, you should warm it slowly first, using a separate pan over a medium-low heat.
Of course, buttermilk isn’t only used in sweet dishes. It also makes a great marinade for meat, as the lactic acid helps to break down proteins, tenderising the meat. In particular, it is popular as a coating for southern fried chicken, keeping the meat tender and juicy, and also providing a good, thick coating for the flour and seasoning to stick to. Other meats, particularly pork or skirt steak, are often tenderised using buttermilk, and it is also used to make ranch dressing, America’s favourite salad dressing since 1992.
If you have some buttermilk leftover after your latest cooking project, it also makes a creamy, refreshing drink - ice cold from the fridge is best. Buttermilk is a popular drink in Indian, Nepalese, Pakistani and Arab households, where it is often still made in the traditional manner. In India, it is known as chaas, and can be flavored with salt and spices, while in Arab countries it is called leben and is popular during Ramadan, when it is drunk during iftar and suhur, meals eaten just after sunset, and just before sunrise.
There are several things you can use as a replacement for buttermilk, if you’re craving some breakfast pancakes without the trek to the store to buy ingredients. The usual stand-in is regular milk with a small amount of something acidic, like lemon juice or vinegar. Use a tablespoon of either for every cup of milk, stir well, and let it stand for a few minutes before using. You can also use cream of tartar at a ratio of 1¾ teaspoons per cup of milk, thin yoghurt, or sour cream mixed with a little water.
Now you’ve got the lowdown on all things buttermilk, it’s time to get baking. This buttermilk cupcake recipe makes the lightest, fluffiest cupcakes we’ve ever tasted, with a hint of tangy buttercream and sweet vanilla, and a zesty lemon icing, all topped with a luscious red cherry. Perfect as a dessert, or for a spot of afternoon tea with friends.
Or for a traditional Southern recipe, try these homemade buttermilk biscuits. Serve warm, with butter or honey, or stuffed with eggs and bacon for a hearty breakfast, or try some good old fashioned biscuits and gravy.