Ingredients 101: Buttermilk
Although buttermilk has been around for centuries, more recently it’s become in demand by home cooks who are buying it for the first time to make the splendid recipe by chef and author Samin Nosrat for her Buttermilk-Marinated Roast Chicken.
I think that unless you grew up on a dairy farm, or have taken an interest in fermented and probiotic foods, or are a southern baker, buttermilk may be completely unfamiliar to you. If that is the case, some background and food science are in order, as are tips for buying buttermilk since not all sold in our grocery stores are the same.
What Is Buttermilk?
True buttermilk is a fermented dairy product made from the liquid that remains after cream has been churned to make butter. But contrary to the name “buttermilk,” this liquid is low-fat and contains no butter.
When butter was made by hand-churning, the cream or milk that is used to make the butter was first fermented to help thicken and develop more flavor. Then with the agitation from the churning, the fermented cream separated with the milk fats becoming butter, and leaving behind a thin, watery liquid. This liquid, which would have retained its fermentation, thickened and developed a tangy flavor, making what was a popular, low-fat drink and cooking ingredient called buttermilk.
By the 19th century, new technology was developed using centrifugal separators that enabled sweet butter to be produced without having to first ferment the cream, making it faster and less expensive to manufacture butter. But this meant that the watery byproduct liquid that was essential for making buttermilk would no longer be produced, leading to shortages. In response to consumer demand, by the early 20th century, a new kind of buttermilk was created by heating ordinary skim or low-fat milk and adding lactic acid cultures, resulting in a low-fat liquid with the same flavor and creamy consistency as traditional buttermilk. This product is called “cultured buttermilk” and unless you have access to a dairy farm that still makes it the traditional way, it's what we buy today.
Cultured buttermilk is delicious and healthy. What does it taste like? To me it tastes like a pale version of plain yogurt. If you’ve chosen one that has live cultures, it is a tasty source of the same probiotics and active cultures as found in natural yogurt, kefir, kombucha, sauerkraut, kimchee, and other fermented foods that promote gut health. And despite its rich and creamy texture, it is decidedly low-fat.
How to Buy and Store Buttermilk
Some buttermilk fans have their favorite brands based on both flavor and whether it will be drunk as a beverage or used in cooking. Calories and fat levels can also be an option because cultured buttermilk is now made as yogurt or sour crème are, meaning you can buy skim or full fat versions, although most of what’s sold in our groceries is low-fat cultured buttermilk.
If you’re going to be using your buttermilk in cooking or baking, keep in mind that traditional or homemade (more on that in a moment) buttermilk will be thinner and less acidic than the cultured kind and this could impact a recipe that is using buttermilk as part of leavening, as in biscuits.
There are recipes for making your own buttermilk, such as this one from The Food Network. I’ve not tried to make my own since I can buy a wonderfully creamy and flavorful one (I'm partial to the Five Acres Farms brand) at my local grocer, but being a DIY home cook (my Worcestershire sauce is outstanding, if I can boast a bit) I think it’s a great idea to give it a try, but keep in mind it may not be as effective in a recipe as store bought.
Buttermilk, like many probiotic foods, has a long shelf life. Still, if you have some left over after a recipe, which is the case for me when I make the Samin Nosrat Buttermilk-Marinated Roast Chicken, the good news is that buttermilk freezes beautifully. You can freeze it in any kind of container, including ice cube trays if you’re not sure of how much you may need for future recipes.
Cooking With Buttermilk
Buttermilk is a common ingredient, especially in baking (it adds tenderness) and in many southern recipes. Buttermilk scones or biscuits or waffles come to mind. But it’s also used in pound cakes, cornbread, and muffins as well as cake icings and ice cream bases.
It’s a major element of salad dressings, as with ranch dressings which are the most popular salad dressings in America (take that, vinaigrette!). It can add tang and creaminess to smoothies. I’ve seen recipes in which buttermilk is a substitute for coconut milk in curries, used in fried chicken batters, added to marinades (the cultures can help tenderize meat or chicken while adding flavor), and it’s very popular as an addition to mashed potatoes or grits.
Here’s a New York Times recipe for Ranch Dressing by Julia Moskin that includes buttermilk both as liquid and aspowdered buttermilk, which is listed as an optional ingredient but is included for added flavor. You can buy powdered buttermilk at KingArthurFlour.com.