The Baking Soda myth

[Lana]

So often I read through recipes that call for the addition of an acidic ingredient to ensure that the Baking soda/ Baking powder reacts, and the cake rises. However, Baking soda/powder reacts to produce the required gases once it is heated in the cooking process. So why do the authors of these recipes insist that there is an acidic component to their cakes??

 

[Norcalbaker59]

So often I read through recipes that call for the addition of an acidic ingredient to ensure that the Baking soda/ Baking powder reacts, and the cake rises. However, Baking soda/powder reacts to produce the required gases once it is heated in the cooking process. So why do the authors of these recipes insist that there is an acidic component to their cakes??

Sodium bicarbonate (baking soda) is an alkaline (base). It’s water soluble.


When heated to 180°F (80°C), sodium bicarbonate undergoes a thermal decomposition reaction in which one molecule of CO2 to every two molecules of sodium bicarbonate is released (1:2 ratio of CO2 molecule to sodium bicarbonate molecules).

But when the alkali is mixed with an acid, it creates a different chemical reaction. An acid chemical reaction produces a 1:1 CO2 molecule to sodium bicarbonate molecule. So full leavening is achieved with half the amount of molecules. Plus, as soon as the sodium bicarbonate comes in contact with water and acid, it triggers the chemical reaction. So leavening begins without heating to 180°F (80°C).

In a creamed butter better, if it sat until it reached 180°F without the leavening activated, the creamed butter would be already be melted, so unable to capture the CO2 in the butter pockets to create good lift. In a dough or batter without creamed butter, the activation would occur long after starch gelatinization (122°F/50°C), and protein denaturation (144°F/60°C). These reactions create the structure of the baked goods. If leavening happened at the end of these chemical reactions, there would be very little lift

Baking powder is a mix of sodium bicarbonate and acids.

Most baking powders contain two acids.
Baking powders are double-acting, meaning they activate, go dormant then activate a second time.

The first activation happens when the acid comes in contact with water. The second activation happens when the acid reaches a temperature of 140°F/50°C, so below the temperature of the completion of starch gelatinization and protein denaturation.

 

[retired baker]

So often I read through recipes that call for the addition of an acidic ingredient to ensure that the Baking soda/ Baking powder reacts, and the cake rises. However, Baking soda/powder reacts to produce the required gases once it is heated in the cooking process. So why do the authors of these recipes insist that there is an acidic component to their cakes??

when you see recipes that call for both bs and bp you may ask why.
same with recipes that contain bs but no bp.

soda has other properties, it can control batter flow.
consider CC cookies with soda, the cookie batter spreads outward but doesn't rise much.

 

[Norcalbaker59]

when you see recipes that call for both bs and bp you may ask why.
same with recipes that contain bs but no bp.

soda has other properties, it can control batter flow.
consider CC cookies with soda, the cookie batter spreads outward but doesn't rise much.

Baking soda does not determine the spread of cookie dough. It's the sugar type and percentage of sugars to flour and the ratio of egg to flour that determines spread.

Brown sugar with it's molasses = thicker, chewier cookie with less spread.

Granulated sugar = thin, crispy cookie with more spread.

However, the percentage of baking soda to flour can effect texture.

But the OP’s question is about the cause/trigger of the chemical reaction (decomposition) of baking soda that is used for leavening. The answer is baking soda does not spontaneously decompose. It requires heat and/or an acid. We use acid for the reasons I started above.

 

[retired baker]

Baking soda does not determine the spread of cookie dough. It's the sugar type and percentage of sugars to flour and the ratio of egg to flour that determines spread.

Brown sugar with it's molasses = thicker, chewier cookie with less spread.

Granulated sugar = thin, crispy cookie with more spread.

However, the percentage of baking soda to flour can effect texture.

But the OP’s question is about the cause/trigger of the chemical reaction (decomposition) of baking soda that is used for leavening. The answer is baking soda does not spontaneously decompose. It requires heat and/or an acid. We use acid for the reasons I started above.

"Baking soda also serves another important purpose when it comes to cookies: It encourages spreading by raising the mixture's pH, which slows protein coagulation. This gives the dough more time to set before the eggs set, which results in a more evenly baked cookie.Jan 24, 2023

What Does Baking Soda Do In Cookies? - Allrecipes "​

 

[Wockneys]

Sodium bicarbonate (baking soda) is an alkaline (base). It’s water soluble.


When heated to 180°F (80°C), sodium bicarbonate undergoes a thermal decomposition reaction in which one molecule of CO2 to every two molecules of sodium bicarbonate is released (1:2 ratio of CO2 molecule to sodium bicarbonate molecules).

But when the alkali is mixed with an acid, it creates a different chemical reaction. An acid chemical reaction produces a 1:1 CO2 molecule to sodium bicarbonate molecule. So full leavening is achieved with half the amount of molecules. Plus, as soon as the sodium bicarbonate comes in contact with water and acid, it triggers the chemical reaction. So leavening begins without heating to 180°F (80°C).

In a creamed butter better, if it sat until it reached 180°F without the leavening activated, the creamed butter would be already be melted, so unable to capture the CO2 in the butter pockets to create good lift. In a dough or batter without creamed butter, the activation would occur long after starch gelatinization (122°F/50°C), and protein denaturation (144°F/60°C). These reactions create the structure of the baked goods. If leavening happened at the end of these chemical reactions, there would be very little lift

Baking powder is a mix of sodium bicarbonate and acids.

Most baking powders contain two acids.
Baking powders are double-acting, meaning they activate, go dormant then activate a second time.

The first activation happens when the acid comes in contact with water. The second activation happens when the acid reaches a temperature of 140°F/50°C, so below the temperature of the completion of starch gelatinization and protein

Very helpful to know the background technicalities of this.

 

[Lana]

Sodium bicarbonate (baking soda) is an alkaline (base). It’s water soluble.


When heated to 180°F (80°C), sodium bicarbonate undergoes a thermal decomposition reaction in which one molecule of CO2 to every two molecules of sodium bicarbonate is released (1:2 ratio of CO2 molecule to sodium bicarbonate molecules).

But when the alkali is mixed with an acid, it creates a different chemical reaction. An acid chemical reaction produces a 1:1 CO2 molecule to sodium bicarbonate molecule. So full leavening is achieved with half the amount of molecules. Plus, as soon as the sodium bicarbonate comes in contact with water and acid, it triggers the chemical reaction. So leavening begins without heating to 180°F (80°C).

In a creamed butter better, if it sat until it reached 180°F without the leavening activated, the creamed butter would be already be melted, so unable to capture the CO2 in the butter pockets to create good lift. In a dough or batter without creamed butter, the activation would occur long after starch gelatinization (122°F/50°C), and protein denaturation (144°F/60°C). These reactions create the structure of the baked goods. If leavening happened at the end of these chemical reactions, there would be very little lift

Baking powder is a mix of sodium bicarbonate and acids.

Most baking powders contain two acids.
Baking powders are double-acting, meaning they activate, go dormant then activate a second time.

The first activation happens when the acid comes in contact with water. The second activation happens when the acid reaches a temperature of 140°F/50°C, so below the temperature of the completion of starch gelatinization and protein denaturation.

Thanks for that! I now have a much better understanding of these processes- there are so many variables to consider

 

[Mona]

Baking soda needs an acidic ingredient to activate and produce carbon dioxide gas, which helps the cake rise. Without an acid, baking soda won't work effectively. Baking powder, however, contains both an acid and a base, so it doesn't need an extra acidic ingredient. Many recipes include an acidic component to ensure baking soda works properly and to help give your cake a nice rise.