FAQ – Is my baking powder or baking soda fresh?

Do you ever make a recipe and it just falls flat (literally or figuratively)? You followed the recipe exactly, but it didn’t turn out at all like the pictures? One reason for this may be your baking soda or baking powder isn’t fresh anymore.

If your baking soda or powder is old or not fresh, it won’t have the same leavening power. Although the general guideline for both products is that they’re good for up to 2 years before opening and 6 months after, this isn’t always the case. If you live in a climate that is humid, for example, it can deteriorate faster. Which is why it is always a good idea to test for freshness if you’re at all unsure about it.

The Difference Between Baking Soda and Baking Powder

Let’s talk a little about the difference between these two leavening agents. Although they are closely related (let’s call them cousins), they are actually very unique from each other in the way they work. 

Baking soda is a base, which means it will always need an acid (vinegar, lemon, yogurt, etc) in a recipe to interact with it and create carbon dioxide. This balance is essential to baking soda working in the way you want it (as a leavening agent) instead of just causing the recipe to taste bitter.

Baking powder has baking soda in it, but it also has a dry acid (cream of tarter), which means your recipe doesn’t need an additional acidic ingredient to neutralize the baking soda. You’ll also see that baking powder usually is advertised as “double acting,” which just means that the leavening agents start working when the baking powder is introduced to liquid, as well as when it’s heated.

Why Do I Need it in My Recipe?

It may seem redundant to add these to your recipe when you already have your starter. However, sourdough starters (including Amish Friendship Bread starters) rely on the activity of the yeasts, which, in general, causes a slower rise time. Both cause a chemical reaction, which helps reduce rise time. It also allows home bakers to use their starters, fed or unfed, with their favorite recipes while still getting that subtle but delicious Amish Friendship Bread tang.

Testing Baking Soda for Freshness

You need some acidic type of liquid to test your baking soda. Use distilled white vinegar or lemon juice, if you have on hand.

• Place a teaspoon of baking soda into a small bowl.
• Add approximately 3 tablespoons of distilled white vinegar.
• If the baking soda bubbles a lot, it is still fresh.
• If the baking soda doesn’t react or only bubbles slightly, it isn’t fresh anymore.

Testing Baking Powder for Freshness

Baking powder is slightly different in its properties, which means you need to test its freshness in a different way. Another caveat when it comes to baking powder is that it doesn’t last quite as long as baking soda. The general consensus of shelf life is around 1 year for baking powder (before opening).

• Place a teaspoon of baking powder in a heat-safe bowl.
• Add ¼ cup of boiling water to the bowl.
• If the baking powder bubbles up a lot, it is still good.
• If it doesn’t react or only reacts slightly, it is no longer fresh.

Remember to store your baking powder and baking soda in a cool, dry place to keep moisture out.

Additional Resources

If you’d like to see a video of how this is done, check at Alton Brown’s YouTube channel which is always fun to watch (see below). And don’t forget to check out our master library of FAQs, or any of our tutorials to help you if you have any other questions!