Salt, baking powder and baking soda in cake batter

Cake recipes have just a small amount of salt, baking powder and/or baking soda. But salt and leavening agents have a big impact on the taste and texture of a cake.

Four fork each with a bite of cake at the end against a gray background — The same pound cake recipe made with none, 1 tsp, 2 tsp and 3 tsp baking powder (left to right)

In the first Cake Batter class we started the process of taking apart and examining the original pound cake recipe which uses only flour, eggs, sugar and butter in equal parts.

Neither salt nor leaveners are a part of the original pound cake formula. I think that cakes baked from the original recipe are a little dense and taste a bit flat.

Now we’ll learn about two additional ingredients in cake batter; salt & leavening agents.

To learn general information about the types of salt and how they work in baking, please visit the Baking Ingredients – Salt post. This class will specifically cover how salt works in cake batter.

What is a leavening agent?

A Leavening agent, or leavener, is a term for an ingredient that makes dough or batter rise.

How salt, baking powder & baking soda work in cake batter:

Now we’ll explore how the addition of salt and chemical leaveners can improve the original pound cake. These two ingredients are used in very small measure, but have a major impact on both the flavor and the texture of the cake.

I baked 9 pound cakes to test the effects of salt and baking powder, with wildly varying results.

Eight pound cakes lined up on a white background

What Salt does in Cake Batter:

A ½ teaspoon less or more of salt may not make much difference in a pot of soup, but it can make a great deal of difference in cake batter. My testing proved that, for our pound cake recipe, a little salt goes a long way.

Salt is not only a flavor enhancer. Salt also affects the tenderness of a baked good.

Salt molecules form strong bonds with flour proteins, causing the gluten molecules to become less mobile, which, in turn, makes the batter tighter and more elastic. This is a desirable trait in a bread dough, but is definitely not desirable in a cake batter.

I baked several cakes to test how salt changes the pound cake’s flavor and texture. All the cakes were made with room temperature ingredients and were baked in identical 9×5 loaf pans at 325°F in a convection oven.

Testing varying amounts of salt in pound cake

As a control, I first baked a pound cake using only the four original ingredients and the reverse creaming method. Consistent with previous tests, the cake was fairly dense with a soft tender crumb and a slightly flat taste.
For the next test I added a ½ teaspoon of table salt to the batter. The difference between the first and second cakes was really surprising.
The cake with the added salt baked up higher due to the stronger gluten in the batter, and had a noticeably more chewy bite. The flavor was better than the first cake, less flat and more well-rounded, but the loss of tenderness was not good.
I reduced the amount of salt to ¼ teaspoon for the third test. I found that was just enough salt to improve the flavor, yet keep the tenderness of crumb.

Now that we have just the right amount of salt in the cake, we can move on to the leavening.

Two pound cakes on a white surface with a gray background — The cake on the left has no salt and the cake on the right has 1/2 teaspoon of salt. The salt made the cake rise higher and have a tougher texture.

About Baking Powder in Cake Batter

Please visit the Baking Ingredients – Chemical Leaveners page to learn all about the science of baking soda and baking powder. This class will discuss the specific effects that baking powder has on pound cake batter.

Based on the rule that 1 teaspoon of baking powder creates enough lift for each cup of flour in the batter, the correct amount of baking powder for our pound cake recipe should be about 1 ¾ teaspoons baking powder.

Testing varying amounts of baking powder in pound cake

To test the ideal amount of leavening for our pound cake I baked 3 successive cakes, using 1 teaspoon, 2 teaspoons and 3 teaspoons of baking powder.
The difference between the three cakes was quite striking. The cake made with 1 teaspoon of baking powder was nicely domed with a slightly open crumb.
The cake made with 2 teaspoons of baking powder had a lighter, more open crumb and started to flatten a bit at the top, but it was still acceptable.
The cake made with 3 teaspoons of baking powder collapsed down the middle because the batter could not hold the excess carbon dioxide. The crumb on cake 3 was rough and spongy.

Of the three cakes, I preferred the one made with 1 teaspoon of baking powder. It had a little lightness from the leavener, but retained the traditional pound cake texture.

Four slices of pound cake lined up on a white background

The same pound cake recipe made with none, 1 tsp, 2 tsp and 3 tsp baking powder (top to bottom)

Four pound cakes standing side by side on a white surface with a gray background

The same pound cake recipe made with gradually more baking powder. Too much leavener caused the last cake to collapse.

How baking powder is mixed into cake batter matters

It may be hard to believe, but there is yet another factor to consider regarding chemical leavening. How you add the leavening to the batter will affect the texture of the cake crumb.

What causes tunnels and holes in cake?

Leavening that is not thoroughly and evenly distributed through the batter will result in a cake with an uneven crumb and scattered tunnels and holes. You may even get an unpleasant bite of raw baking powder.

Testing the best way to mix baking powder into cake batter

For the final round of tests I mixed 1 teaspoon of baking powder into the batter in 3 different ways.
For the first cake I sifted the baking powder with the flour and then mixed the sifted ingredients together on low speed for a full 20-30 seconds before adding the butter.
For the second test I sifted, but did not take the time to premix the dry ingredients before adding the butter.
For the third cake I did not sift or premix the dry ingredients.

Three slices of pound cake arranged on a white background. Each cake has a different texture. — 1 tsp baking powder is sifted and mixed, is just sifted and is not sifted or mixed (from top to bottom)

Once again, the difference between the baked cakes was clearly visible even before tasting. The first cake had a nice even crumb, the second cake had a slightly rougher crumb with some holes and the third cake had a rough open crumb with tunnels and holes throughout the cake.

Sifting and pre-mixing the leavening is definitely worth the few extra seconds it takes.

Other cake batter classes:

Next up: Cake Batter Class #3 will explore The function of flour in cake batter.

When we’re done experimenting with all the ingredients for this “cake batter” course, we’ll use all we’ve learned to create Pound Cake Perfection.

pawan

Friday 29th of October 2021

I am not clear on usage of salt in cake. If i am making a cake with 1 cup or 1.5 cups or 2 cups of APF then the the salt qty of 1/4 tsp remains same Or this has to be increased with increasing qty of flour

KathrynT

Wednesday 15th of June 2022

@Eileen Gray, I was taught if the recipe calls for APF use APF, and if the recipe calls for cake flour, use cake flour. Is that wrong?

Eileen Gray

Saturday 30th of October 2021

First of all, I personally would not make a cake with all purpose flour. Read through the Flour in cake batter post to get more information about the different flours. Regarding the amount of salt in the cake based on the amount of flour, I don't have a set formula. The point of the post is to show how salt does make a difference in the batter beyond just flavor. I found that using 1/4 tsp salt for 1 3/4 cups of cake flour gave me the exact flavor and texture I wanted. If you are creating a cake recipe from scratch you can start from there. If you're following a recipe but you're not happy with the outcome the amount of salt is one thing to look at. If you find the cake too chewy and notice that the amount of salt seems high try reducing the total amount of salt to see if that helps. You can also read about The Cake Formula to see how all the ingredients in cake batter interact.

Patricia

Saturday 11th of September 2021

How many teaspoons of baking powder should be used for 5 cups of flour? Thanks.

You need about a teaspoon of baking powder for each cup of flour in a recipe. You can read more general information about leaveners in this post.

Pound Cake

Sunday 28th of February 2021

Awesome post, makes me want to make pound cakes. (:

Great. Try this recipe for Perfect Pound Cake.

Elizabeth C

Monday 29th of June 2020

I'm making a pound cake using a recipe I'd used as a base before. Just the classic recipe. But I wanted to tweak a few details, adding the salt and baking powder. So I did a search and found this amazing useful article! My only problem at this moment is I measured out everything by weight, especially because we're dealing with Pound Cake. My Cake Flour measurement is off by 1/2 cup! To reach 225 grams I needed 2 1/4 cups. I'm really concerned about the balance of the recipe. Nothing I can do now except go by weight and hope I don't mess it up. For the future, when you have this much variance, do you think weight is more important or volume? Thank you!

Tuesday 30th of June 2020

Measuring by weight is always more accurate because an oz is always an oz or a gram is always a gram. Measuring by volume will vary based on how you fill the cup. I use the "dip and sweep" method. That is where you dip the cup into the bin to fill it up and then sweep it level. If you use the method where you spoon the flour into the cup you'll likely end up with less flour because as you spoon the flour you are fluffing it up and adding more air. So a cup of flour can weigh more or less based on how it's filled. For my recipes you can assume a cup of cake flour weighs 4.5 oz or 126g.

Karen

Saturday 19th of October 2019

This is the most thorough explanation on the use of leavening agents in baking that I have come across (including many cookbooks) and I greatly appreciate the time, patience and money you spent testing the cakes and publishing the results,

I have been struggling with a very old recipe for plum spice cake that keeps falling in the middle and your post may actually help me sleuth my way to a fix. Thank you!

Sunday 20th of October 2019

That's awesome, Karen! I spent months doing research for my series on cake ingredients and cake batter. I'm so glad it's helpful. I have a private Facebook group for discussing recipes. Just ask to join and I'll add you to the group. It's a great place to troubleshoot recipes.