The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

baking powder versus baking soda

dlassiter's picture
dlassiter

baking powder versus baking soda

Several recipes I've used require BOTH baking powder and baking soda. Baking powder is clearly a leavening agent. What exactly is baking soda FOR? These recipes use buttermilk, which is somewhat acidic, so I suppose baking soda could also act as a leavening agent. But why use both? Why not just use baking powder?

mariana's picture
mariana

Why not just use baking powder? Because acid in buttermilk adversely affects cake quality. As acidity increases, cakes have less volume and a gummy, pudding-like texture. Color decreases and browning decreases at higher levels of acidity.

Soda neutralizes acid, but that alone may not be enough to completely leaven the product, thus baking powder is also added.

dlassiter's picture
dlassiter

OK, so you're saying that baking soda is there mainly to neutralize acid, and it is therefore more necessary in baked goods that use buttermilk or maybe yogurt. Now, I would have thought that baking powder itself was capable of neutralizing acid. In fact, baking powder is really just baking soda with an acidifying agent. The former neutralizes the latter and leavens in the process. So if it's so important to neutralize the acid why are you adding something that acidifies the mix? Seems to me that if you have an already acidic mix, baking soda ought to work fine by itself.

The Roadside Pie King's picture
The Roadside Pi...

My understanding is that baking powder ( double acting,) as it is know. Contains banking soda plus another chemical leviening agent. I believe it is the baking soda that needs heat to activate. The other leviening agent is activated as soon as it hits water. Thus you have double acting baking powder.  As always I yield to your expertise. This is something I read long ago. 

dlassiter's picture
dlassiter

In an acidic mix, you certainly don't need heat to get CO2 out of either baking powder or baking soda. But yes, if you DON'T have an acidic mix, heat will cause both baking soda and baking powder to break down, releasing CO2.  In an acidic mix, I still don't understand why you'd need both.

tpassin's picture
tpassin

Baking soda starts reacting and liberating CO2 as soon as the acid hits it.  It doesn't have to wait for heat.

Baking powder carries its own acidic compound, and starts reacting when it gets wet.  Double-acting baking powder undergoes a second CO2-releasing reaction when heated.  The acid in baking powder apparently neutralizes its own alkaline.

In my recent soda bread bakes, I wanted to get more leavening power but I also didn't want to use more baking soda for fear it would add an unpleasant taste.  So I added some baking powder.  It worked very well.

The standard amount usually given for leavening is 1/4 tsp baking soda for 1 cup flour. For neutralization I have read 1/2 tsp for 1 cup of buttermilk.  You can work out if your hydration will let you use enough (or too much) baking soda for the amount of flour.

Fun fact - before commercial yeast became widely available, UK bakeries leavened bread with baking soda and muriatic acid.  So did some households.  After baking powder became available, British home bakers mostly changed over to using it but the Irish stuck with baking soda - maybe because they loved their buttermilk and had a lot of it (in many cases it was really milk that was souring and needed to be used up before it was too late).

The Roadside Pie King's picture
The Roadside Pi...

While we are on the subject, what, if any issues would I encounter if I trippled the soda bread formula to fashion a huge mishe size bread? Thanks in advance for your guidance.

Photo of last year's Irish soda bread. For the cracker Jack crew at Banner imaging, Mesa.

tpassin's picture
tpassin

Darned if I know.  Follow the standard guidance of 1/4 tsp soda per cup of flour, add some more baking powder like I did, I would think it would work out.

A larger dough mass will have less surface area relative to its interior.  So there will be less surface to lose gas, and more gas relative to the surface being generated in the interior.  OTOH, there will be more internal pressure to overcome because of more weight.  Hard to say how those factors will balance out but I bet it will come out OK.

If you have a large dutch oven, I would bake it in that.  The looks will be a little different from a free-standing loaf but traditionally Irish soda breads were baked in big pots on a fire.  I think a pot would help keep the loaf's surface from drying out by the time the interior has cooked enough.  Finish up with a period with the lid removed. Also if you bake in a pot, getting the liquid right becomes less critical, because even if the dough is a paste that you can't shape into a ball you can still scrape it into the pot.  Works great!

I baked several of mine in a pot that I didn't even preheat, and the result was super.

This link may encourage you:

https://lovetovisitireland.com/county-louth-bakery-holds-world-record-for-largest-irish-soda-bread/

122 Kg of flour!

The Roadside Pie King's picture
The Roadside Pi...

For both your own insite and the link I will surely enjoy later!

Moe C's picture
Moe C

"In October 2104 a  Droheda-based bakery has succeeded in baking the largest loaf of soda bread ever recorded."

It's in their future. :)

alcophile's picture
alcophile

Here's another fun fact. Before baking soda and baking powder became widely available, ammonium carbonate was used as a leavening agent. The (NH4)2CO2 was derived from deer antlers, hence the other term for it, hartshorn salt or just hartshorn (German: Hartshorn = deer antler).

Its advantage in baking is that no water is generated during the leavening process, only NH3 and CO2, making it especially suited to thin cookies and crackers. Thicker or moister doughs would probably retain some of the NH3. The substitution is 1:2 hartshorn/baking powder. I suppose you would consider it a single acting baking powder, with only the heat-activated step producing the leavening.

I've never used it but the NH3 liberated probably smells bad during baking!

albacore's picture
albacore

Just like in baking powder, ammonium carbonate is often mixed with another salt = potash, aka potassium carbonate. I've used the mix when making Lebkuchen once or twice.

It is a bit stinky in the oven, but soon flashes off. As you say, only used for thin goods as otherwise it's diificult to get rid of the embedded ammonia.

Also I read that hartshorn is now not recommended as the nitro compounds encourage acrylamide formation.

Lance

alcophile's picture
alcophile

What would be a suitable substitute for the hartshorn in those recipes that specify it? Was one recommended? Offhand, I can't think of a compound that would have the same properties as (NH3)2CO2.

albacore's picture
albacore

This is one article I read:

https://www.chemistryviews.org/details/ezine/11280255/Hartshorn_Salt_Chemistry/

Or, if you want to dig deeper:

https://www.lgl.bayern.de/lebensmittel/chemie/toxische_reaktionsprodukte/acrylamid/ue_2016_acrylamid_lebkuchen.htm

https://www.n-tv.de/ratgeber/Wie-gefaehrlich-sind-Lebkuchen-article16474031.html

https://www.deutsche-handwerks-zeitung.de/acrylamid-und-cumarin-lebkuchen-und-zimtsterne-unter-verdacht-147935/

Ironically it seems that home produced Lebkuchen have higher levels than commercial.

Hartshorn still seems to be used in Germany, but reading some of those articles, it seems like there is a swing away from it.

I don't think there is any substitute other than baking powder!

Lance

trailrunner's picture
trailrunner

for years. To make authentic Biscotti Regina , for instance, one must use it. We always bought them at Brocatos in NOLA. We got the recipe from a relative when we moved away. It’s a key ingredient and you will find it listed on various baked cookies and crackers industry wide. 

There is no issue with excessive odor when used appropriately. Yes you can smell a faint bit of ammonia during the baking process but it dissipates quickly. The advantage to using it is the incredible crispness it produces and the slight cracks on the surface and none of the bitterness associated with baking powder/ soda. 

Ammonium Bicarbonate is easily purchased online. It needs to be stored tightly sealed . It’s shelf life when kept airtight in the freezer is years as we have discovered. 

I think this is the best most accurate explanation for why one uses both baking powder and baking soda 

 

https://www.thekitchn.com/baking-soda-and-baking-powder-103763

Yippee's picture
Yippee

and it's a must-have for making the delicious pineapple crust of our famous pineapple buns. Without it, they just wouldn't be the same!

Yippee 

dlassiter's picture
dlassiter

Let's get back on topic. I don't understand why a recipe would call for BOTH baking powder and baking soda. BOTH reduce acid, and BOTH provide leavening. In this recipe, the buttermilk provides the acid, so baking powder, which acidifies the mix, really isn't necessary. Do I understand that baking powder has less taste? Then why not just use it alone and leave out the baking soda entirely?

tpassin's picture
tpassin

Baking powder probably does not reduce acid since it includes enough acid to react its own baking soda (or whatever equivalent is used).  Too much baking soda, especially if not neutralized, can add an unpleasant taste, so I read. Too much acidity can make for a tough crumb. OTOH, unneutralized buttermilk adds a nice tang. Oh, well, can't have everything, I suppose.

My thinking, therefore, is to use the amount of buttermilk needed for the right hydration, enough baking soda to neutralize the buttermilk, and if that's not enough leavening, add some baking powder.  Of course, these amounts are only going to be rough approximations.

It is often said that baking soda helps with browning.  I *think* (I'm not sure about this) this is the case for unneutralized baking soda.  Otherwise baking power powder would do the same thing, but it doesn't in my experience.  So this might be a reason to use a little more soda than needed for neutralization.

In my case, I'd like to use baking powder rather than soda when possible because it don't make you rush the product into the oven so fast.  The baking soda goes to work and produces gas as soon as you add the buttermilk or acid, but double-acting baking powder has that second wind effect.

Don't forget, many recipes are probably written by people who don't really know why they are including or excluding amounts of baking soda and baking powder. They copy other recipes, use their mothers' explanations, what have you.

Good thing the whole process isn't very critical!

dlassiter's picture
dlassiter

Yes, I agree with most of that. But I think you mean that baking POWDER does not reduce acid since it includes acidification. Now one ingredient in baking power IS baking soda, so it isn't as if adding baking soda supplies something that is missing.

tpassin's picture
tpassin

But I think you mean that baking POWDER does not reduce acid since it includes acidification.

Yes, that's what I meant. I better go back and edit my post.

pmccool's picture
pmccool

Baking soda is a right now leavener.  As soon as it comes in contact with an acid, it begins to react and produce carbon dioxide.  The baker must move very quickly to get the biscuit, cake, brownie, cookie, whatever, into the oven after the shortest possible mixing time so that the baked good can take its finished form in the oven before the reaction runs its course.  Too slow and you wind up with flatter baked goods.

Baking powder offers two stages.  The first works exactly like baking soda.  The second requires the heat of the oven to trigger the acid+base reaction that generates additional carbon dioxide, making it more likely that the baked good will have the desired degree of inflation.

Recipes that call for both leaveners use a belt and suspenders approach.  The baking soda and baking powder together provide an initial rapid release of carbon dioxide for leavening whatever is being made, plus another shot of carbon dioxide while baking.  In effect, it's an insurance policy that the finished product won't turn out flat instead of fluffy while relieving the pressure on the baker to do things as fast as possible.

Paul

dlassiter's picture
dlassiter

That's helpful, but one has to wonder why two shots of carbon dioxide are needed. My carbonate-leavened baking just uses baking powder. They never turn out flat.

BrianShaw's picture
BrianShaw

The recipes I associate with both baking powder and baking soda tend to be the heavier batter breads, like bannanna bread, date nut bread and cranberry bread. It's been my assumption that the additional soda was not just for browning but to give the heavy batter a better lift before the batter sets in the early bake, while the double-acting baking powder continues the rise during htat time. I also assume that using more baking pwder instead of the added soda would make the bread rise and crack too much. Some crack is nice but too much crack...

dlassiter's picture
dlassiter

Well, if you don't want too much rise, then just don't use as much baking powder. But yes, one might suppose that one is shooting for different amounts of rise in different stages of the bake. There are  many descriptions of the difference between baking soda and baking powder for leavening, and they ALL say simply that one requires an acidic mix, and the other doesn't. So then, um, why would you ever need BOTH? There must be a solid answer to this, but I don't think we've quite hit on it. If you ever need both, they must be doing fundamentally different things.

Now, this is interesting. Baking soda can produce a lot more gas than baking powder. So one can't simply substitute one for the other. Maybe because there isn't as much baking soda in baking powder.

Evidently I'm not the first one to ask this question.

https://www.reddit.com/r/AskCulinary/comments/z821no/whats_the_point_of_using_baking_powder_and_baking/?rdt=61144

So the confusion about this is somewhat rampant. Not any really good answer there either. But evidently yes, baking soda does enable the Maillard reaction aiding browning, and it may actually aid gluten formation. But the main reason to add it is to cut down the acidity. It will do that a lot better than baking powder. That being said, still not obvious why you need both. Baking soda is cutting down the acidity by making CO2, and it does that better than baking powder. So it's doing the majority of leavening AND cutting acidity. That being the case, what's the baking powder for?

tpassin's picture
tpassin

The way I'm approaching it is to try to use the amount of baking soda for the acidic component, like buttermilk, and if I find I'd like more gas production, add some baking powder.

In reverse, if I'm making (US) biscuits where I want an especially tender crumb, I use baking powder and milk, not buttermilk. If I want some tang, I use buttermilk.  I use baking powder anyway as the main leavener because biscuits take more time between mixing and baking than a plain soda bread.  You have to roll or pat out the dough, cut the biscuits, reroll and cut the the scraps, and possibly brush the tops, all before baking. The delayed action of baking powder is a help here.

But probably, most people use one or the other because that's the way they learned.  It probably doesn't have any deep reasons for it.

dlassiter's picture
dlassiter

OK, so the baking soda is there primarily to get rid of the acidity. It does that very effectively, and also leavens very effectively. If you need additional leavening, then maybe the only recourse is to add baking powder. But gIven that the leavening power, with acid, of baking soda is about three times that of baking powder, you'd think that adding an equal amount of baking powder (as it in in my southern cornbread recipe) won't add much leavening.

Though I think it was noted earlier that baking soda without acid still releases CO2 when the temperature gets above 180F. If that's the case, one might wonder why anyone would EVER need baking powder.

tpassin's picture
tpassin

I think I recall that you need four times a much baking powder as baking soda to get the same leavening power.  You don't just use a 1:1 ratio.  And it's hard to know why any particular recipe writer chose a particular value.  For my recent soda breads I'm using 5.4g baking soda (which I got from another recipe) and I added 7.2g baking powder.  It's not a large amount, and maybe it doesn't really do much but I like the results I've been getting so I've just stuck with it.  I came up with that amount before I had read up on the relative effectiveness of powder and soda.  It's a pretty arbitrary number.  I bet most recipes are like that.

I should probably experiment with larger amounts, now that I know more.

dlassiter's picture
dlassiter

Yes, I've heard the number three. But I could accept four. This recipe used a teaspoon each of baking soda and baking powder. Now if that baking soda is worth three teaspoons of baking powder, adding one teaspoon of baking powder sure isn't going to make much of a difference in the leavening that happens.

BrianShaw's picture
BrianShaw

What is the recipe?  That seems an unusual combination of leavening.

 

Have you considered doing an experiment to test your hypothesis?  Bake “whateveritis” and leave out the baking powder. See what happens. Could be very useful information that will help get past the abstract discussion a bit easier. 

tpassin's picture
tpassin

Here's my latest soda bread bake.  The dough was a thick paste that I scraped into a Pullman pan.

Irish Soda Bread

Adapted from
https://www.seriouseats.com/real-irish-soda-bread-recipe

Flour Weight   420    Total Dough 842
               Baker’s Percent   Actual Weight
Flours
=====
AP                       80            336
malted barley      10             42
Irish-style WW     10             42

Other
====
Liquid buttermilk  95.2          400
Salt                       1.7            7
Baking soda         1.3            5.5 (0.9 tsp)
Baking powder     2.4           10   (2 tsp)

As I wrote earlier, I used an amount of baking soda not based on what I learned from later reading. And, yes, some experiments will probably be in my future.  This bread was darn good, though!

BrianShaw's picture
BrianShaw

Hi Tom. That’s a normal leavening for a heavy batter bread, in my experience  I’ll bet it will be good!

My last message was intended for @dlassitter, especially enquiring about the recipe with 1 tsp  each of baking powder and baking soda. That combination is quite foreign to me. Apparently I didn’t respond specifically to his post so it may have seemed a generic (or out of place) question   

tpassin's picture
tpassin

Hi Tom. That’s a normal leavening for a heavy batter bread, in my experience  I’ll bet it will be good!

It was really good, and with the Pullman form factor it tasted well without drying out much,  A freestanding version would dry out faster because of the very rough jaggedy crust.

 Apparently I didn’t respond specifically to his post so it may have seemed a generic (or out of place) question   

It's just that the indentation of the posts made it hard to know which one you had in mind.

dlassiter's picture
dlassiter

Well, we haven't made much progress here. The issue isn't what the recipe was. The issue is WHY the recipe got away with calling for BOTH leavening agents. I've seen several recipes like this. It's not that foreign if you're looking for it. I'm beginning to believe that this combination was just made up out of whole cloth to make these recipes look a little more complicated. I mean, if no one can think of a reason for it, that's all one has left.

trailrunner's picture
trailrunner

https://www.thekitchn.com/baking-soda-and-baking-powder-103763

hope this satisfies your quest . Guess not… good luck. 

dlassiter's picture
dlassiter

Well, that's a good try. Haven't heard that one yet. "You could use baking powder alone, but then your finished baked treat might taste too acidic." I guess the problem with that is that the whole purpose of baking powder is to create enough acid for the baking soda in it to neutralize it and produce CO2. That is, yes, baking powder produces acid, but it also gets rid of it. But for goodness sake. It's a buttermilk recipe. You WANT it to taste acidic.

dlassiter's picture
dlassiter

So here's a recipe for "soda bread" that uses both baking powder and baking soda. It is said in the description that  "Traditionally, soda bread is leavened with just baking soda, hence its name. But adding a little baking powder helps lift and give a lightness to the crumb that is harder to achieve without the round shape of a boule."  So why not just use baking powder? Ah, but maybe the soda is there for flavor?

https://www.washingtonpost.com/food/2024/03/15/soda-bread-focaccia/

Except they don't really taste much different. They are both sodium bicarbonate (baking soda), but baking powder has an acidifier. If you taste the latter, it tastes like baking soda, but it comes with a fizz.