Kitchen Basics: Baking Soda v. Baking Powder....The Mystery Revealed!

Thursday, November 10, 2011

They're both white. They're both used in baking. And they both look like crack. But often we have no idea which is which, and why we use one versus the other in recipes, or even more confusing, the times we have to use both! With holiday baking rapidly coming upon us like ants on a picnic, I jumped at the chance to write a posting about it at my good friend Chandra's suggestion. So, here we go!

Baking Soda is also known as sodium bicarbonate. This is fancy pants AP chemistry class lingo for "salt with stuff in it." In fact, the natural appearance of baking soda is more like kosher salt, but often it's ground up into a powder form that we all are familiar with. Specifically, it includes the combination of the chemical compound known as nitrate and sodium carbonate, which is effectively limestone. Sodium carbonate (basically a naturally occurring salt found in rock, plants, etc.) has been and is continued to be used for a variety of purposes, ranging from cooking to softening water in washing machines to aiding taxidermists in taking flesh off of skulls in the needless preservation of killed animals. But when combined with the compound nitrate, it becomes a cooking tool, so we'll just focus on that for now.

notice the sandier texture of baking soda

Sodium bicarbonate or baking soda in cooking is used as a leavening agent. This means, when added to stuff it helps the stuff rise. So this is why we use it in baking and not in savory cooking. Basically it reacts with the acid in your baking ingredients. So when your recipe calls for ingredients like buttermilk, yogurt, cocoa powder, vinegar, cream of tartar, coffee, etc. the acid in these ingredients will react with the baking soda to let the batter rise by way of releasing carbon dioxide. When you place the batter in the oven, the hot temperature activates the reaction, and the the air created from the carbon dioxide adds mass to the stuff you're cooking.

So basically baking soda when working with other acidic ingredients makes your stuff get bigger and puff up in the oven, which is what you're looking for when you're making cakes and stuff.

Now it gets complicated...

Baking powder is basically baking soda with extra acid added to it, then ground up into a powder form. Why would we need to add extra acid to baking soda you may ask? Well, what if you don't have easy access to more "expensive" ingredients like buttermilk, yogurt, oranges (orange juice is obviously an acid and was a rather luxurious commodity back in the day) or even cream of tartar (also considered a lower level acid)? Now you get to use baking powder to make your cakes, scones, and muffins and biscuits. The way baking powder works is all you need is flour, eggs, flavorings (spices, etc.), liquid (often plain milk) and the baking powder to make your batter or dough rise. So it affords you more options, which is why you'll see more often than not that baking powder is included in recipes instead of baking soda, unless you're specifically working with OJ or buttermilk, etc. that require the use of baking soda.

Baking powder works the exact same way -- the added acid to the powder combines with the other ingredients to create carbon dioxide, which in turn creates mass and volume when heat is applied.

baking powder has a more powdery appearance, like flour
Now, does this mean you can never use baking powder when working with other acids like buttermilk or yogurt? Absolutely not. What happens is you need to adjust the amounts. So if you have a recipe or are fiddling with a batter that has buttermilk in it and you're shit out of luck and only have baking powder to work with, simply reduce the strength of the baking powder by half. If you don't, you're doubling up on the the acid in the batter/dough, which will create a metallic or acidic taste after baking.

Another big difference between the two is timing. Baking soda reacts instantly to the liquid acid in the batter, so you need to mix it all, throw it in the pan, and get it in the preheated oven immediately before it begins to lose it's leavening power. If you don't, it won't rise properly in the oven and look weird. Baking powder on the other hand has a longer life -- you can let the batter sit for up to 20 minutes before putting it in the oven. In fact, some recipes may even call for you to do so. And you will notice when working with baking powder, it will begin to puff up and thicken if you leave it out before filling your cupcake tins or what have you. So for this reason many people prefer the kindness of baking powder's longevity.

To complicate things even further, some recipes calls for both baking powder and baking soda. WTF would you need to use both, if both of them are doing the same exact thing the same exact way? Turns out there is a method to the madness...

One teeny tiny caveat to using baking soda is sometimes baking soda by itself isn't enough to handle the work. Remember, baking soda puffs up the stuff you're working with, but it also neutralizes the acid from the other ingredients you're using. So it raises your batter/dough at the same time it balances out the flavors for you. Now, sometimes the ingredient you're using may be a little too acidic. Hello freshly squeezed orange juice or lemon juice! When the acid in certain ingredients are simply too overpowering, there's not enough oompf in the baking soda alone to lift the batter; all the energy is going to neutralizing the acid. So, baking powder joins forces with baking soda, so one can do the neutralizing and one can do the heavy lifting. And together they make cake.

This is why it's very important to read your recipes carefully when baking. Measurements need to be exact; a little too much of this will throw the balance off of that. And with baking unfortunately and unlike savory cooking, you can't taste as you go; you need to wait until the finished product to see if you fucked up or not. Which is why I personally hate baking cakes and all of it. But, with a little knowledge and research, you can make the call for a good recipe and one leading you down the path of disaster.

A couple of other notes to close...

These are considered "active" ingredients. They're ALIVE!!!!! You're basically using baking soda and/or powder in place of yeast (also alive) when baking. So you have to make sure they're not dead. To do this, simply pay attention to your expiration date -- if it's expired it's done, don't even try to push it like you do with the milk or yogurt a few days after. Second, you can take a tablespoon of the stuff and dissolve it in water -- if it bubbles or fizzes then it's alive and ready to use; if it duds it's dead.

Before any period of intense baking coming up like now, I just go out and buy a new container of each to be on the safe side.

In terms of the acidic compounds you should know commonly used in baking, they include (but are not limited to):
  • buttermilk
  • sour cream
  • yogurt
  • citrus juice -- orange, lemon, grapefruit, lime, etc.
  • cocoa powder -- EXCEPT for Dutch unprocessed
  • chocolate
  • vinegar
  • honey
  • molasses
  • brown sugar (because it includes molasses in it)
  • maple syrup
  • fruit juices -- strawberry puree for example, canned peach, nectars, etc.
The reason I give you this list is to double check the recipes you're working with. Make sure the adjustment for baking powder has been made. Well, first make sure that if you're working with the ingredeints, baking powder is included someone in there! And if not, skip the recipe and try something else.

Hopefully this sheds some light on the differences between the two, and it helps decipher some confusion among baking recipes and making treats this holiday season. Happy baking!

1 comment:

Chandra said...

Thank you, thank you, thank you!!!! I GET it now.
This has been a question on my mind for as long as I can remember...ahhhhhh....