Become a better baker by learning the real differences between baking powder and baking soda—in easy-to-understand language!
Welcome back to my Baking Basics series!
Today I’m discussing one of the most confusing subjects in the entire realm of baking. What is the difference between baking powder and baking soda? Are they the same? Can I sub one for the other without changing anything else?
If there is one thing that you take away from today’s lesson, let it be this: baking powder and baking soda are absolutely not the same.
Baking powder and baking soda are both leaveners, however they are chemically different.
What is Baking Soda?
Aka bicarbonate of soda or sodium bicarbonate.
Let’s start with baking soda because it’s the most confusing. First, baking soda is a BASE. Do you remember the science experiment we all did in school? Mixing baking soda with vinegar and watching an eruption of bubbles? Usually we did this in some sort of model volcano contraption. I know you know. When you mix baking soda (BASE) with vinegar (ACID) you get a chemical reaction (an eruption of bubbles!). A product of this reaction is carbon dioxide.
The same exact reaction happens in our cookies, cakes, breads, etc. When a recipe calls for baking soda (BASE), it usually calls for some type of ACID like buttermilk, brown sugar, yogurt, lemon juice, vinegar, cream of tartar, molasses, applesauce, natural cocoa powder (not dutch process), or honey. You need this ACID in the recipe to react with the baking soda, which in turn creates carbon dioxide and allows your baked good to rise.
Baking soda is strong. In fact, it is about 3-4x stronger than baking powder. More baking soda in a recipe doesn’t necessarily mean more lift. You want to use *just enough* to react with the amount of acid in the recipe. Too much baking soda and not enough acid means there will be leftover baking soda in the recipe. You do not want that; it creates a metallic, soapy taste in your baked goods. Ick.
Good rule of thumb: I usually use around 1/4 teaspoon of baking soda per 1 cup of flour in a recipe.
Baking soda CAN leaven a baked good when exposed to heat. However, unless it is neutralized with an acid, your finished baked good will likely have a metallic aftertaste—like I mention above. Get it? Got it? Good.
What is Baking Powder?
Baking powder contains baking soda. It is a mixture of baking soda, cream of tartar (a dry acid), and sometimes cornstarch. These days, most baking powder sold is double acting. This means that the first leavening occurs when baking powder gets wet—like when you combine the dry and wet ingredients in the recipe. (This is why you cannot prepare some batters ahead of time to bake later—because the baking powder has already been activated.) The second leavening occurs when the baking powder is heated.
Double (first, second) acting.
Since baking powder already contains an acid to neutralize its baking soda, it is most often used when a recipe does not call for an additional acidic ingredient. Like my sugar cookies. However, this isn’t always the case. You can still use baking powder as the leavening agent in recipes calling for an acidic ingredient. Like my lemon blueberry cake. In my recipe development, I based my lemon cake recipe off of my vanilla cake recipe. I used buttermilk (acid) instead of regular milk for added moisture and a little tang and subbed a little brown sugar (acid) for granulated sugar—again, for added moisture. I was pleased with the rise and taste of the cake, so I did not experiment with using baking soda.
Good rule of thumb: I usually use around 1 teaspoon of baking powder per 1 cup of flour in a recipe.
Why do some recipes call for both?
Some recipes call for both baking powder and baking soda. These recipes contain some sort of acid (yogurt, brown sugar, etc), however the carbon dioxide created from the acid and baking soda is not enough to leaven the volume of batter in the recipe. That’s why baking powder is used as well—to add necessary lift.
Basically, the reason for both is because sometimes you need more leavening than you have acid available in the recipe. It’s all about balance.
Another reason to use both baking powder and baking soda is because they affect both browning and flavor. Food & Wine breaks it down easily: let’s take my birthday cake pancakes recipe. In my recipe, buttermilk is used partly for its tangy flavor. If we used only baking soda, it could neutralize all of the buttermilk’s acid. And we’d lose that tanginess! However, by including baking powder as well (which has its own acid), some of the buttermilk’s flavor is left behind, and there is still enough leavening for fluffy pancakes.
How to Substitute Baking Powder and Baking Soda
It’s tricky, which is why I never recommend it without background knowledge (and the expectancy that your baked good will not taste as intended).
If you have a recipe calling for baking soda, you might be able to substitute baking powder. However, you will need up to 4x as much baking powder to get the same amount of leavening. And, depending on the recipe, you might end up with a baked good that’s a little bitter with that much baking powder. You can sub baking soda for baking powder only if you increase the amount of acid in the recipe—which likely changes the taste and texture of your baked good. You’d also need less baking soda since it is about 3-4x stronger.
So, uh, just stick to the recipe!
Don’t Forget—They Expire!
I replace my baking powder and soda every 3 months, just to be sure they are always fresh for my recipes. I always date them on the bottom of the container. If you don’t bake often, chances are you’ll have to test your baking powder and soda for effectiveness before using.
How To Test Baking Powder
To test baking powder, pour 3 Tablespoons of warm water into a small bowl. Add 1/2 teaspoon of baking powder. Give it a light stir. The mixture should moderately fizz if the powder is fresh. If there is no reaction, toss the baking powder and buy a fresh package.
How To Test Baking Soda
To test baking soda, pour 3 Tablespoons of white distilled vinegar into a small bowl. Add 1/2 teaspoon of baking soda. Give it a light stir. The mixture should rapidly bubble if the soda is fresh. If there is no reaction, toss the baking soda and buy a fresh package.
That’s it for today! Did I completely bore you? Hello?
For anyone still here, don’t forget that baking is CHEMISTRY and it takes practice, trial and error, and the willingness to learn in order to succeed.
Stay tuned for a massively tasty chemistry project tomorrow. Cookies!
Wow that was so helpful!! Thank you for sharing. (:
Finally. A concise and clear explanation! Never have had it told so we’ll!
Thank you !
This is very helpful. Easily written to understand. Thank you so much.
We’ll done! Love this breakdown of bs vs bp. And love your recipes!
This is the best article related to food I have ever read .Thank you so much for this detailed explanation and for this enthusiasm
Thank you so much for this simplified break-down. I have been using your recipes and I love your work. My favorite so far is your Scones.
Great article! Loved your writing as it has so much personality! I have always wondered about the difference between the two and now understand why some of my baked goods are fabulous or a flop!
Great post! Should be required reading. Just discovered the hard way when I (twice) grabbed the baking powder when it called for baking soda. Finally figured out what happened and the third time out the recipe was perfect. Did not understand the underlying chemistry and why some recipes call for one and not the other.
It is not intuitive. As always thanks for your help
Always wanted to know. Now I do. 🙂
This is very interesting I had a recipe one time for Scottish biscuits, they are really cookies and they were from the 1890s I think. I lost the recipe but it cool for 6 cups of flour And all three of the baking powder, baking soda, and cream of tartar they were the best cookies ever but I can’t remember the amounts of the baking powder baking soda and cream of tartar are used. I also used confectionery sugarMixed with a pound of butter.
Hey Sally, thanks for writing these articles. It makes a lot of sense and I appreciate you walking us through the science of baking in an easy to stomach manner. I have a question – you mention that you replace my baking powder and soda every 3 months. I don’t bake that often and given recipes call for such small amounts of both, is there a way to increase the shelf life of either/both soda and/or powder? Just curious. Thank you!
Hi Suchita, we’re so happy you enjoy these blog posts – thank you so much for reading! Storing baking powder and soda in an air tight container (away from moisture) can help extend the shelf life.
I Googled differences between these two for a recipe that calls for them both, but I only have the powder. I clicked on this article and it answered the questions I didn’t even know I had! This is so amazingly thorough, explains everything to bits. Thank you so much!
I have been baking ever since I was a little kid, but it’s always been other people’s recipes. Now, at 25 years old, I want to begin creating my own recipes, so thank you so much for all this advice! It is definitely helping me be successful with my new hobby!
That was very helpful. Thank you!
Hi Sally, I have read your articles on baking soda v baking powder, however, I just want to clarify, can I omit the soda from the moist chocolate cake recipe if I have used dutched cocoa. I have made them a couple of times now and they erupt – just like you said – like a volcano! I found reading your articles very useful and want to perfect these yummy cakes!
Looking forward to your response.
Gillian
Hi Gillian, Dutched cocoa will change how the cake bakes and tastes, and that switch would require additional testing. If you test anything out, please let us know. Or if you find a chocolate cake recipe you love that calls for dutched cocoa, let us know too! Natural cocoa really is best for this particular chocolate cake.
I’m becoming baking obsessed, and I love your posts like this one that give me the kind of basic understanding of technique and ingredients that I couldn’t learn otherwise. And I love the way you say things! Thank you!
This is the best explanation of the difference I’ve ever read! Simple, straightforward language with the science background so we really know what we’re doing, and the freshness tests too.
The explanation was so clear and was very helpful! Thanks for sharing 😀
Thank you so much for doing this article! VERY clear and simple language, which made it very appealing to follow the explanations to the very end, well done! Appreciated!
Sally, you explained it very well, l like your style. Thank you.
Oh Sally, love reading your posts and tecipes. It’s always very clear, simple and easy to understand.
Thank you! Definitely help a beginner homebaker like me a lot!
Sally, as a retired chemist, I can confirm that this is a great explanation of the differences between baking soda and baking powder. I agree that good baking is good science, which may explain why I’ve enjoyed learning about baking from you. And, in these experiments, it’s OK to taste the results!
Thanks for the clear and concise explanation. I have been comparing recipes for a particular bread-type dough and found that some call for powder and some for soda, now I have a clearer idea of how to choose my recipe ingredients (I like to tinker with and sometimes mix-match-combine recipes into one perfect [for me] recipe).
Thank you SO much for this valuable explanation. I have been scouring the internet to understand the difference and yours is by FAR the most comprehensive. I am not a baker but during this lockdown I attempted to make something that required baking powder. All I had was baking soda … and seriously, that’s ALL I tasted when it was done. Lol I know to lessen the amount of baking soda now or wait until I can find baking powder (which is next to impossible). Thank you!
Super great explanation! Exactly what I was looking for, and could not find ANYWHERE else. Thank you!
Hi I just found your blog and love the well thought out explanations on the science behind the baking. However I’m disappointed when you use the worlds nerd and geek. I know you’re trying to be funny but please don’t apologize / warn your readers about giving them intelligent information. I have a pre teen daughter who loves baking and I would love for her to use your blog as a resource. Please just give the information. You can still be funny and have personality in your blog. I want to encourage my children’s curiosity and point them to resources that explain why things happen. Your readers are already at your site because they want to find out the science. Don’t make them feel bad about the amount of knowledge you have or bad about the knowledge that they are receiving.
Thanks for your insight, Ann! Appreciated! This post could use an update. 😉
Hi,
I totally loved this scientific explanation!! I have always asked myself why one is used instead of the other! This is the first time I have read a convincing explanation! So, that being said, I will definitely follow your blog for delicious recipes since they are “scientifically” proven recipes….lol Thanks
Thanks so much! This post absolutely clears everything up. I knew you couldn’t substitute them, but now I know why and can explain it when my sons ask:)
Yes thanks for this bit of info.
I’m really excited about baking again! I just learned about your blog. I’ve been reading all your tidbits. I just went and tested my baking powder. Let me first say that just looking at the dates told me I needed to throw it out. The first can of baking powder had a 2016 date. It still fizzed. Then I found another can that had a date of 2014 (I’m a little embarrassed.) it did not fizz. My baking soda made lava. It is fine. Ok, now a question. Should baking soda stay sealed? What are your thoughts on using baking soda that has been in the fridge soaking up odors? I think that is all for now. I can’t hardly wait for January 1st to see what the challenge will be. I have a good reason to bake. Oh, I know my other question. What is your opinion on the sliding measuring spoons. I sold Pampered Chef about 20 years ago and still use a lot of it. Thanks, AA
Thank you for all your knowledge. I never had a desire for baking or cooking until lately, and I do love to know the “whys” of what I do, it is like Chemistry. I love knowing all the interactions between the ingredients, which can explain until now I have not been a very good cook. LOL