Skip to main content

How to Use Sour and Spoiled Milk

My milk expired April 24th. Today is May 6th. It's definitely gone bad.

My milk expired April 24th. Today is May 6th. It's definitely gone bad.

It's always such a bummer when I pull out the milk for my morning Earl Grey tea only to discover that it's gone sour.

My typical milk usage fluctuates pretty widely depending on how much baking and cooking I do in a given week. After preparing homemade soda bread and cream of potato soup, the milk is usually running low. But when I don't have time to make dinner, only a small amount gets used up in my tea and coffee.

I feel bad dumping it out, especially when it's half a gallon or more. I'm usually really good about estimating grocery amounts and using up perishable items before they go bad, but milk is such a tricky one.

I've always just assumed there's nothing to be done once it's spoiled but to toss it out, feel a little guilty, and buy more. It seems I was wrong!

My spoiled milk still looks normal here, but it smells very sour.

My spoiled milk still looks normal here, but it smells very sour.

Spoiled Milk at the Office: A History Lesson

Last week at the office, I got out the milk for my coffee and noticed that it had quite gone off. It smelled sour and was even a little chunky. I let the office manager (a wonderful gentleman full of neat tips and stories) know that I was dumping it out due to spoilage, and he shared a fascinating bit of history with me.

His mum lived through the Great Depression when lots of people couldn't afford certain ingredients regularly or didn't have access to them. He said that growing up, she always told him to save the spoiled milk for the pancakes. He said it was perfectly safe and they used to use it in place of buttermilk for baking.

At first, it sounded a little gross, but after thinking about it, I realized that yogurt, cheese, and traditional buttermilk were all historically made from various processes that included spoiling milk. People have been consuming those safely for hundreds of years, so how bad could it be?

My Biscuit Recipe

Scroll to Continue

Read More From Delishably

Baking With Spoiled Milk

Well, I had a carton of milk that expired two weeks ago and was definitely sour, so I decided to try my coworker's tip and bake with it as an experiment. (Actually, it's my roommate's spoiled milk, but somehow I don't think he'll miss it.) I chose my biscuit recipe which normally calls for buttermilk to test it out.

Using the Sour Milk


I made the recipe exactly as I normally would and substituted in the sour milk instead of buttermilk.


Here's now the biscuits turned out. They certainly look fine. So far, so good.


I steeled my courage and ate a biscuit. It tasted pretty much the same as it normally would. It definitely had that bit of sour aftertaste, but it was indistinguishable from the usual taste of buttermilk, as far as I could tell.

And, more importantly, I didn't get sick. I wouldn't recommend drinking spoiled milk by itself, but the heat from baking with it seems to have killed any potentially harmful pathogens that it might have contained.

In conclusion, using spoiled milk as a replacement for buttermilk seems totally legit. In my opinion, squeamishness is the only impediment to this bizarre but effective housekeeping recommendation.

Final Tip

While my recipe turned out fine, I wouldn't advise using spoiled milk in place of regular milk. Since it has a slightly sour buttermilk taste, I recommend using it only as a replacement for buttermilk in your baking recipes.

© 2013 Christy Kirwan

Related Articles