Baking powder versus baking soda: they sound they same, but they are not interchangeable. Although both of these white powders act similarly, the two have a key ingredient difference and thus play different roles in your recipes. Baking soda has been known and used for some time. But baking powder, which can be a proprietary mixture, was not sold and marketed until the end of the 19th century.
Making The Dough Rise
Both baking soda and baking powder are leavening agents. That means they are used in baking to cause dough to rise. Both of them act by releasing carbon dioxide gas, which then bubbles into the dough. These gas bubbles push the dough upwards and outwards, and – voila! – it rises. Then the dough bakes into firmness around the bubbles and retains its leavened shape. Using these leavening agents means that the batter must be baked immediately after mixing as the bubble-producing reaction will run its course eventually. Once the bubbles have all popped before baking, you’ll be left with a bread or cake that refuses to rise in the oven.
Of course, these are not the only ways to leaven your dough. Yeast is another well-known method, most typically used when baking bread, which you can learn with this Udemy course. Yeast is comprised of microscopic fungus cells. These fungi consume the sugars in the dough’s starchy molecules. They release carbon dioxide gas as a by-product of this consumption. Alcohol is another by-product of yeast’s sugar consumption, which is how we get beer, wine, and liquor.
Steam is another method to leaven your dough, as seen in the baking of puff pastry. Thin sheets of dough are folded over on each other in multiple layers. The steam released during baking puffs up the layers, which causes the dough to rise.
How Do They Work?
Baking soda and baking powder release carbon dioxide gas bubbles thanks to a chemical reaction. Baking soda, also called sodium bicarbonate, is an alkaline substance. An alkali is a substance that we call a base – that is, the opposite of an acid – with a pH greater than seven when dissolved in water. (For those who are not familiar with chemistry, the pH scale measures acidity and alkalinity on a scale of 1-14. Water stands at seven, right in the middle. Acids register as the lower numbers, alkalis register as the higher numbers. You can learn more about chemistry with this Udemy course.) Mixing an alkali with an acid neutralizes both of them, yielding the gas-releasing chemical reaction.
Thus, in any recipe the calls for baking soda you will also need something acidic in order to create the reaction. Acidic ingredients that will react with the baking soda include citrus juice, vinegar, sour cream, yogurt, and buttermilk. Even molasses and honey qualify as acidic enough to kickstart the process. Baking soda without an acidic counterpart will not do anything.
Baking powder simplifies the process, as it is made of both the baking soda and the acidic compound in one. (The acidic compound varies according to the brand.) The two are mixed together as dry powders, and do not start their chemical reaction until moistened. In the wet solution, the two chemicals finally interact and release the carbon dioxide. A third stabilizing element, such as corn starch, is also usually included in the proprietary mixture.
Thus, you cannot substitute baking soda for baking powder in a recipe as there will not be the required acidic component for the leavening reaction to occur. Likewise, you cannot substitute baking powder for baking soda in a recipe because the proportions will be off.
Baking powder is typically composed of one-third baking soda and two-thirds of the acidic element and other ingredients. Thus, if you use the same amount of baking powder in your recipe as the baking soda asked for, you would only be using one-third of the right amount and the dough will not rise as much. Tripling the baking powder will increase the presence of the acidic elements to a noticeable degree, leaving a bitter taste.
You can make your own baking powder easily enough. Just use baking soda and cream of tartar, mixing one teaspoon of the former with two teaspoons of the latter and using it immediately.
Cream of tartar is scientifically called potassium hydrogen tartrate. It is not a creamy substance, but is in fact a fine white powder. This powder is derived from tartaric acid, and is frequently culled from the inside of wine barrels as a by-product of fermentation. In addition to acting as an acid in baking powder, cream of tartar is useful for stabilizing and stiffening whipped egg whites in soufflés or meringues.
Using Baking Soda or Baking Powder
Baking soda and baking powder – in leavening dough – act swiftly. Yeast may take its time to rise, but the reactions that result from these powdery substances are fast-moving. Thus, they are suitable not for regular bread but for the cakelike breads we call “quick breads.” Baking powder can also be what is called “double-acting.” This means it reacts and creates bubble first when it is mixed with liquid. It then continues to react a second time when it is heated. Thanks to this second reaction, which happens in the oven, using double-acting baking powder means you can wait about 15 minutes between mixing and baking.
Quick Breads and More
Banana bread or zucchini bread are leavened with baking powder or baking soda, and not yeast. Yeast can take hours to rise, whereas these breads are leavened and ready to bake as soon as they are mixed.
Cornbread and soda bread are other examples of beloved quick breads that use baking powder or baking soda in order to rise. Other delicious baked goods that qualify as quick breads include muffins, biscuits, and scones. Even pancakes are a sort of quick bread, just with more liquid in them.
For instance, Irish soda bread uses the leavening powers of baking soda – and not yeast – in order to rise. The traditional ingredients are flour and salt mixed with baking soda and acidic buttermilk. The lactic acid in the buttermilk reacts with the baking soda, giving the resulting bread its airy soft texture. Recipe variations include butter, egg, raisins, nuts, or seeds to flavor the bread further.
Baking soda – as it must be paired with an acidic ingredient in order to make dough rise – is used in recipes that call for that other acidic element. It can leave a slightly noticeable bitterness behind. When cooking with acidic ingredients like buttermilk, chocolate, or even honey, baking soda is the chosen quick leavening method. Baking soda is commonly called for in cookie recipes.
Baking powder – since the acid is already mixed in – is used more often with neutral-tasting ingredients like milk. Baking powder is more commonly used in cakes and biscuits.
When using either baking soda or baking powder in your recipes, always sift it with the other dry ingredients first. Mixing it evenly in with the flour ensures even distribution and uniformity – and will help you avoid large clumps of the leavening agent leading to large holes and unevenness in the final baked good. Waiting to mix the dry and wet ingredients until the end prolongs the start of the reaction. And over-mixing may beat the bubbles out of the batter, so many recipes suggest you stir only until uniformly moistened.
Too much baking powder will not only cause your baked goods to taste a little bitter but will also cause them to rise too quickly and then collapse. (The bubbles get too big and pop.) Too little baking powder will be overly dense and tough to chew.
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