Let’s take a quick minute to talk about buttermilk.
What is buttermilk? Buttermilk is a slightly sour milk. The sourness of buttermilk comes acids in the milk, most notably, lactic acids. Because the proteins in buttermilk are slightly curdled, buttermilk is slightly thicker than regular milk, but not quite as thick as cream. Buttermilk is also usually much lower in fat than regular milk and cream.
Say you wanted to make some butter and buttermilk waaaaay back in the day. First you’d take your fresh milk from the cow, let’s say a big old bucket full… and you’d leave it out at room temperature for a few days. After a few days the rich cream would separated and formed a thick layer on top of the milk. During these few days, the milk would fermented a bit from the lactic acid forming bacterias in the milk. Gross? Not at all! The bacteria produced would help lower the pH of the milk and protect with milk from icky microorganisms, making the butter easier to churn. Once the butter is churned the residual liquid that’s produced…. that’s buttermilk!
Nowadays, buttermilk is a whole other production. Cultured buttermilk, as it is called in the United States these days, is a pasteurized milk product. Instead of letting the milk ferment naturally, most dairies now add a culture of lactic acid bacteria to produce the same thickening and curdling of the milk. Many dairies also add tiny yellow colored flecks of butter to simulate the old fashioned product.
Buttermilk is an important part of baking. The acidic milk combined with baking soda in a recipe is a baker’s dream. See… when baking soda is combined with the lactic acids of buttermilk, the soda releases carbon dioxide that when heated, released tiny bubbles that expand and lift and lighten whatever you’re baking.
But what if you’re plum out of buttermilk? There are solutions…. let’s talk.
In a pinch and you’ve run out of buttermilk?
Lemon and Milk
In a 1-cup measuring cup, add 1 Tablespoon of fresh lemon juice. Top the lemon juice with with skim, low fat or whole milk. Stir and let sit for two minutes. After two minutes, your milk is both acidic and curdled. Perfect!
Yogurt and Milk
Mix 3/4 cup plain yogurt with 1/4 cup of milk. Stir and make it a quick substitution for buttermilk.
Milk and Cream of Tartar
Mix 1 cup of milk with 1 3/4 teaspoon cream of tartar. To ensure that the mixture doesn’t get lumpy, mix the cream of tartar with 2 Tablespoons of milk. Once mixed add the rest of the cup of milk. Cream of tartar is an acid and will simulate the acidic environment of buttermilk in a pinch.
Evan
I use vinegar as well. Now I never have to buy buttermilk again!
linda
thanks for another great & informative post…lemon & skim milk…always in my frig!
joy, where did you get the slice of tree prop…i have the lemon, i have the 1 cup china measure (mine from anthropologie)…but the slice of tree looks so perfect(pls do not tell me you chopped it & cleaned it & sealed it!). thanks.
joythebaker
the board is from a company called Boards by Joel. and yes.. i love the little measuring cups from anthro… super precious.
linda
thank you so for your reply!
googled & found on vermont avenue in la….
Wendy
cool – thanks!! in your opinion, where does powdered buttermilk fall on the spectrum?
joythebaker
you know…. I’ve never used powdered buttermilk, but Kate of SavourFare uses the stuff with success. Just add water, right? Presto… buttermilk!
Aimee
I’ve started to always keep a jug of buttermilk around. I can’t do without it for pancakes, salad dressings,cakes and buns. I love that tang taste that it brings to food!
Jessica @ How Sweet It Is
I LOVE baking with buttermilk but so many times I don’t have it or it is expired. I read on your site once that your do use it when it is expired…but how expired??
Mom24
Thank you for this. A question I have is how long is it safe to use buttermilk? I’ve been told it’s way past the expiration date, but I always struggle with how long is too long?
joythebaker
Good question. I use my buttermilk up to two weeks past the expiration date. It it smells extra sour or looks extra chunky then I pitch it and get a new carton.
Mom24
Thanks! That helps.
the projectivist
oh i love it when i learn me sumfink!
Michelle
I’ve always done it as milk and white vinegar – in the same way as the lemon as described above. :)
M
Kaye
I used a tablespoon of white vinegar for every cup of milk to substitute for buttermilk.
joythebaker
Perfect!
Shauna
I had heard of the lemon and milk substitution, but as I strangely never seem to have lemons on hand, that solution hasn’t really been an option for me. But Cream of Tartar – that’s brilliant!! I always have that on hand (hello, snickerdoodles!), so that would be a fantastic solution. Thanks for the amazing tip!! :)
joythebaker
Sure Shauna! If you don’t have lemon on hand, a tablespoon of white vinegar also works per one cup of milk.
Shauna
It’s a good thing you archive this website, which absolves me of the responsibility of writing all of these golden nuggets down. ;) Thanks!
Junglewife
Thanks for the info! I can’t get buttermilk here where I live (or fresh milk either – grr!) so I’ve been using vinegar and milk. I also make my own yogurt, so I’ll remember that for the future. I would’ve never thought to use cream of tartar!
Cate
Thank you for this! I haven’t found buttermilk here in Korea, so I’ve been using lemon and milk and it works great. I had no idea yogurt and milk was another option!
Maja
Thank you so much for this! I was just at foodgawker, went to a blog with cake that had buttermilk in it and just thought, oh, great, where am i gonna buy that, then i said to myself, let’s see what Joy has written and imagine my delight when i saw the title. :) Again, thank you! :)
Susana
Thanks so so so much for this tip!!!
By the way ‘FIRST’! hehe!