Baking Soda vs. Baking Powder

You have probably heard of baking soda and baking powder. In fact, if you have ever baked before, you probably used them! But do you know what they are or what they do exactly?


I am highlighting both baking soda and baking powder at the same time because they are similar (but not a substitute for each other). Baking soda can also be called sodium bicarbonate, and it is simply a base compound.

Hearty Bread


In baking, baking soda acts as a ‘Chemical leavening agent’, which basically means it ‘rises’ the dough or batter. If you didn’t have any leavening agents, your bread, cookies, and cakes would be flat and dense instead of raised and fluffy.  So how does it work?


When the baking soda mixes with an acid (something like buttermilk, yogurt, or vinegar), it reacts by making a lot of bubbles. These bubbles help spread the dough apart until it rises. The problem with baking soda, is that it will react right away and then sizzle out after a few minutes. This can be a problem because when you are baking cookies, cake, or bread, you need the dough to rise slowly over the cooking time to stay fluffy. That’s where baking powder comes in hand.

 Baking powder = Baking soda + 2 acids + Fillers


The first acid is called Monocalcium phosphate. Remember how I said baking soda reacts as soon as it touches the acid? Well this special type of acid reacts with the baking soda only when water is added. Companies use fillers like cornstarch or corn/rice flour to keep the baking powder dry while in the package. In fact, nothing will react until you add wet ingredients to the baking powder.

The reaction with the first acid is still a little too fast, since you need the baked goods to rise while cooking, so companies add a second special acid called sodium aluminum sulfate. This acid only activates when it is wet AND hot (AKA when you put the bread in the oven).

So recap:

  • Fillers: Prevent bubble reactions in baking powder by keeping it dry
  • Sodium Bicarbonate: a base that reacts with acids by forming bubbles (AKA baking soda)
  • Monocalcium Phosphate: The first acid in baking soda that reacts when wet
  • Sodium Aluminum Sulfate: The second acid in baking soda that reacts when wet AND hot

Pretty crazy right? Who knew that these white powdery ingredients could take care of so many chemical reactions in baking!

Banana Bread

Did you know?  You can test to see if your baking powder is soda is working by adding a small spoonful to vinegar. (Volcano experiment anyone?) If it fizzes, keep it…. if nothing happens, its time for some new baking soda!

Stay tuned for this week’s recipe! We will do a little kitchen science of our own with a delicious fruity desert!

Happy Creating!

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