The science behind double acting baking powder Today’s Video of the Day from the American Chemical Society describes the science behind double acting baking powder.
Baking powder always contains at least one solid acid as well as a solid base – usually baking soda – which react when water is added to produce bubbly carbon dioxide.
A double acting baking powder will react and create gas bubbles once when added to a liquid, and then a second time when exposed to heat. Use buttermilk for a rich substitute. Combine equal parts baking soda and buttermilk or plain yogurt. The cultures in these dairy products react with the baking soda to create the gas necessary for leavening your baked goods. Only use buttermilk as a substitute in recipes that already require wet ingredients.
The double-acting baking powder contains monocalcium phosphate, which releases carbon dioxide when heated. Double-acting powder, on the other hand, produces bubbles at the same stage as single-acting powder and then once again as the mixture heats up in the over.
As you can see, baking powder doesn’t go bad in a way of going rancid. It does, however, lose its potency with time. Because of that, if you’ve got baking powder that has been stored for an extended period of time, you should check if it still has potency before using it in baking.
Video Credit: American Chemical Society