My husband inherited a large collection of antique cook books from his grandmother. Many of them depression era books, books from WWI, and WWII which talked about rationing and how to cook with less or with alternatives.
Now I can’t tell you if this was a new idea at that time. I imagine it was something being done for generations, but was just being publicized because people forgot and needed to get back to doing with less. Using up your sour milk is one of the things mentioned in these books.
One was the Royal Baking book from around the 1920 s and 1930 s. In this book there is an entire section on ways to bake with sour milk. In reality, it isn’t much different than baking with buttermilk. One of the things that I have experimented with since discovering this little trick was all the ways I could replace milk with sour milk in a recipe. We always seemed to have an abundance of sour milk on hand. My kids just don’t drink it fast enough.
Sour milk and baking soda create a chemical reaction which produces carbon dioxide. This reaction is the same as using baking powder, and can replace baking powder in many of your recipes. The reaction also removes the sour flavor from the milk.
The trick is to add baking soda to your recipe when using sour milk at the ratio of 1/2 tsp per cup of sour milk.
If your recipe called for baking powder and plain milk (or other liquid), you will need to reduce the baking powder by 2 tsp per 1 cup substitution.
This comes in handy if you are low on baking powder, or for times when baking powder may not be available. When I am living an hour from any store, I won’t be able to just pop out to the store when I run out of baking powder.
Here is a short list of other items you can use to reduce your need for baking power as a leavening agent. Just add one of these, and 1/2 tsp baking soda to replace 2 tsp baking powder.
- 1 cup sour milk
- 1 cup sweet milk soured with 1 tablespoon vinegar or lemon juice
- 1 cup sour cream
- 1 cup yogurt
- 1 cup fruit or vegetable sauces or juice
- 3/4 cup brown sugar
- 3/4 cup honey
- 3/4 cup molasses
- 2 tablespoon vinegar or lemon juice
- 1/2 cup cocoa (not Dutch cocoa, which has been “de-acidified”)
Use as seems appropriate for your recipe.
Sour milk can also be substituted in equal measure for buttermilk in any recipe.