What Is Buttermilk?
Here, a deep dive into what, precisely, this popular baking ingredient is.

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By Fraya Berg for Food Network Kitchen
Fraya is a chef and a contributing writer at Food Network.
When searching for the fluffiest pancake recipe or how to make the tenderest, flakiest biscuits, you’re sure to find dozens of recipes with one thing in common: buttermilk. Why buttermilk? What makes it so special? Is it really necessary? We’ve got answers, from how to make buttermilk to the best buttermilk substitute.

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What Is Buttermilk?
Buttermilk is, quite simply, fermented milk. When you shake and open a fresh quart and pour some into a measuring cup, the first thing you’ll notice is that it’s thicker than milk. Not only is it thicker, but also a little bit lumpy. When you smell it, it has an acidic tang; not sour, but more like a gentle vinegar smell. The flavor is tart, similar to plain yogurt. The acids in buttermilk are what make it so versatile in the kitchen.
For a little more context about buttermilk’s origin, consider the following. If you’ve ever over-whipped heavy cream, you know what happens – you end up with some very fresh butter. If you continue to beat it, you’ll get more butter. By the time almost all of the fat turns to butter, what’s left is the liquid part of the cream. That liquid is buttermilk. It’s made up of water, milk proteins, milk sugars (lactose) and a small amount of fat (about as much as low-fat milk). When butter was made at home, the buttermilk was left out overnight to ferment and thicken on its own. What you buy now is cultured buttermilk. It has live cultures similar to those in yogurt so that it ferments in a controlled environment.

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What Is Buttermilk Used For?
Buttermilk is used when making quick breads such as pancakes, waffles, biscuits and muffins. Buttermilk is made up of a variety of acids – the results of the fermentation process, which give baked goods a couple of benefits. First, the acidity provides tangy flavor to balance all kinds of sweet baked treats. Second, it activates baking soda, producing the gas that makes dough or batter rise. Remember the volcano in grade school? It was made out of acid (vinegar) and baking soda. Third, the acidity breaks down proteins. In baked goods, it acts on gluten, giving you a more delicate crumb.
Buttermilk also has a number of savory applications. It can be used in marinades where its acids tenderize and add flavor to meats and poultry. Case in point: buttermilk brined-chicken recipes, which typically produce miraculously tender, juicy results with very few ingredients. Buttermilk can also be used in place of vinegar when making a base for salad dressing or slaw. Additionally, it’s a popular mashed potato mix-in, adding both creaminess and tang to harmonize the dish’s rich flavors.
Finally, in some cultures, including Arab, Indian, Pakistani and Nepalese ones, it is a beverage on its own. Many smoothie recipes lean on this idea of buttermilk as a beverage and incorporate its thick texture and familiar tang as a counterpoint to fruit.
How to Store Buttermilk
Store buttermilk in its original container in the coldest part of your fridge (not the door, which fluctuates in temperature when you open and close it). Shake well before using because it tends to separate into a watery layer and a thick layer as it rests, and don’t be surprised if it has some small lumps. It’s safe to keep it for a week past the sell-by date. Shake it and pour some into a cup and smell it: that’s the best way to get an accurate idea of its freshness. It will smell tangy when fresh, and sour if it has spoiled.
How Is Buttermilk Different than Milk?
Milk is a fresh dairy product, whereas buttermilk is cultured. It’s fermented with active bacteria – the good bacteria, the type found in probiotics. The fermentation process creates acid in buttermilk and thickens it, giving it a longer shelf life. In addition, buttermilk, at 1% to 2% fat, and is considered low-fat. Milk can have from 0% fat in skim, to 3.25% in whole milk.
How to Make Buttermilk
If you decided to make biscuits or pancakes at the last minute, and don’t have the buttermilk a recipe calls for, as long as you have milk and lemon juice or white vinegar, you’re in luck. No trip to the store required, you can make buttermilk at home.
The substitute for 1 cup of buttermilk is 1 tablespoon of lemon juice or white vinegar in a liquid measuring cup, and enough milk to fill it to the 1-cup line. Stir and let the mixture sit for 5 to 10 minutes at room temperature. It will curdle slightly, thicken and be ready to use.
If you want to make cultured buttermilk, combine 1/2 cup buttermilk with active cultures and 1 quart of whole milk in a container big enough to hold both. Stir, cover with a lid and let it sit at room temperature overnight. It will thicken and become tangy. Let it sit out until it tastes just right to you, then refrigerate it to keep it fresh.
Buttermilk Recipes

Buttermilk brings the yum to a bowl of mashed potatoes. Adding herbs brings it up to a full yum-my. This recipe is ready in a flash, and you won’t miss the butter.

Caitlin Ochs
This buttermilk pancake recipe is the best for lots of reasons, but our favorite is that everything goes in one bowl: less cleanup is always welcome. The resulting pancakes are also as light-as-a-feather. Don’t forget the syrup.

Matt Armendariz
What makes these buttermilk biscuits our go-to? They’re buttery, don’t require a rolling pin or a biscuit cutter and most importantly, they’re ready for the oven in 15 minutes-flat.

Yunhee Kim, Yunhee Kim 2011
When you want to impress, what better way than adding bacon, cheese and chives to a tender and flaky biscuit. Perfect for a weekend brunch or just your favorite Tuesday. If you don’t have chives, substitute thinly sliced green onion.

Antonis Achilleos
With some buttermilk and a few ingredients you probably have on hand, you can have a fresh buttermilk dressing in just minutes. This recipe calls for green onions and garlic, but your imagination can take you anywhere with other herbs: tarragon and parsley, dill and mint or black pepper and chives.

Armando Rafael Moutela, 2013, Television Food Network, G.P. All Rights Reserved 2013, Cooking Channel, LLC All Rights Reserved
The bananas in Banana Buttermilk Waffles do double duty – first in the batter, then as a topping. These waffles are basically buttermilk pancakes with pockets to hold butter, syrup, more banana, whipped cream and whatever else you can think of.

There are so many things about this buttermilk fried chicken recipe that makes it our favorite: the salt in the buttermilk creates a brine, the hot sauce delivers another punch of flavor and the chicken marinates overnight for easy prep.

Kang Kim
Buttermilk plus eight ingredients whisked together and poured into a store-bought graham cracker crust that’s popped in the oven: what could be easier? The tartness of the lemon-buttermilk combo enhances both flavors. A dollop of sweetened whipped cream and a sliver of candied lemon peel are the perfect topping.

Caitlin Ochs
The buttermilk in The Best Banana Bread works magic, tenderizing the crumb and adding moisture to the loaf. The 288 bakers who reviewed it agree that it is everything a best banana bread should be – easy, full of flavor, buttery and moist enough to stay fresh for days. Give it a try with or without the nuts.
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