Manipulating the system
Chemical leavening selection is all about producing just the right amount of gas at the right time in the bake cycle.
“The goal is to maximize the amount of air trapped in the system,” Ms. Book said. “Identifying the optimum amount of leavener is critical. Too little and it won’t rise enough. Too much and there is more gas than the system can hold, and it will collapse.”
Gas retention is also a critical factor in refrigerated dough.
“It is important to minimize the amount of gas released during the chilled holding stage,” Ms. Briggs said. “This is to ensure there’s sufficient gas to rise the dough when it’s baked.”
Leavening systems can be designed to produce a specific desired crumb structure as well as to influence the overall appearance of the product.
“A fine, even crumb structure requires a leavening acid that releases at mixing and a second acid that releases early in the baking cycle to keep the even, small bubbles,” Mr. Mason said. “A coarser crumb structure will have a leavening acid that releases slower in the baking cycle, focusing on making available bubbles bigger rather than making additional smaller bubbles.”
For the overall appearance, a faster system will give a smooth, flatter outer crust, while a slower system will produce a domed, peaked or, on the more extreme side, more craggily “mountain peak” crust. The slower the process, the more the dough will shift from gentle dome to peak to an uneven, jagged top, Mr. Mason explained.
Too much sodium bicarbonate can cause a baked good to have a “soapy” taste and a darker color than usual. This happens when the sodium bicarbonate has not been reacted and neutralized, Ms. Livvix said.
“Some recipes that contain acidic ingredients, such as berries and fruits, require both baking powder and baking soda due to a pre-reaction that occurs in the batter since berries and fruits are acidic,” she said. “It can be challenging to determine how much is enough or too much.”
The leavening system may also impact the color and texture of the baked good.
“An acidic blend, where there is excess acid above what is needed to neutralize the chosen bicarbonate, will lighten the crumb and lower pH, whereas an alkaline blend will give a darker color and high pH,” Ms. Briggs said.
This may actually be useful with color development. A more acidic system will appear whiter, while a more alkaline system can enhance the rich color of chocolate products.
“Achieving the proper chemical balance between acid and carbon dioxide source is critical to obtaining desirable baked characteristics,” Mr. Bright said.