At any given time, I have at least one open box of baking soda and one open canister of baking soda in my pantry, and I never know how old they are. Unlike cheese or apples, none of these leavening agents provide visual clues as to when they have “gone bad”. They look the same regardless of their age, but they just stop working, leaving behind flat, unleavened cakes, cookies, and quick bread. Fortunately, there are two simple tests that you can use to determine the effectiveness of each test.
How we discussed beforehandBoth baking soda and baking soda are chemical leavening agents, but they work in different ways. Baking powder is “pure sodium bicarbonate, an ionic salt with the chemical formula NaHCO3. It is naturally alkaline (basic) with a pH of eight and provides the “base” part of the acid-base reaction. “Baking powder, on the other hand, contains both acidic and basic ingredients that are activated by adding water. To see if baking soda works, you need to introduce it with some acid. To test the baking soda add some water.
To test your baking sodaPour three tablespoons of white vinegar into a bowl or cup, then stir in half a teaspoon of baking soda. For baking powderAdd half a teaspoon of baking soda to three tablespoons of water. Either way, the leavening agent is still good with the solutions bubbling and you can feel safe as you continue baking. If they’re not bubbling, it’s time to refill them (and write the date on the new package this time) – even though you do can replace one with the other when your sourdough needs are urgent and immediate. (You can also use either to clean and scrub withprovided cleaning does not depend on a robust acid-base reaction.)
This post was originally published in 2014. It was completely rewritten and released on May 3, 2021 to add more specific information and to comply with the latest Lifehacker style guidelines.
