You may know that baking powder is a leavener. The old-fashioned term is “lifter.” When the leavening agent is mixed in a batter, carbon dioxide (CO2) bubbles are released in the batter and create “lift” to make the cake, cookie or bread light with air pockets.
The baking powder we use at home is “double acting.” The Ingredient Label will read: Cornstarch (to keep the mixture smooth and dry), bicarbonate of soda (baking soda), sodium aluminum sulfate (reacts when heated) and acid phosphate of calcium (reacts with the soda when moistened). With this combination, the baking powder “acts twice”--right away when the batter is moistened and then in the oven when heated, to produce a consistent release of leavening bubbles in the batter.
You can observe the “lift” created by conducting the following experiment.
1. Fill a wide mouthed clear glass jar or container with hot water (160 degrees F).
2. Add 5-6 skinless, salted peanuts.
3. Stir in 2 teaspoons baking powder.
Q: What do you observe first? Over two to five minutes, what do you see begin to happen? What do you think makes the peanuts rise and fall down in the mixture?
A: Bubbles begin fizzing right away because the heated water reacts the leavening agents. As CO2 bubbles form around a peanut, they will lift to the surface. When they get to the surface the bubbles break and the peanut sinks again until more bubbles will form around it and it will rise again.
||Bicarbonate of Soda (Baking soda) =2NaHCO3
Sodium aluminum sulfate=NaAl (SO4)2
Learn more about baking powder at www.clabbergirl.com