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Sorting Out Leavening Agents

Country MoonScents of cinnamon, nutmeg, and cloves fill most kitchens this time of year. Even better than the treats themselves are the childhood memories that they bring back.

Sometimes re-creating those delicious treats can be a bit challenging, as hand-me-down recipes are sometimes vague. This is especially true when it comes to leavening agents because they can be so confusing. So, I decided to get to the bottom of this rising issue.

Baked goods need something to help the dough rise or "leaven." This something can be anything that produces gas in the dough to cause expansion. The simplest way to do this is by manually turning the dough or beating air into it. However, this method usually doesn’t give enough rise to bread, souffles, cakes, and other desserts. A substance that produces gas — namely carbon dioxide gas — is usually needed. Yeast, baking soda, and baking powder are the three main agents that are used in baking to produce this lift. They can be used singly or in combination. The big question is knowing which one to use when.

Yeast are little organisms called fungus which, when activated, consume the sugars in flour and releases carbon dioxide as waste. Whenever yeast is used, the dough usually needs to be kneaded, which means turning the dough out on a floured board and actually working it with your hands. When dough is kneaded, a protein inside produces a stretchy matrix called gluten. This traps the tiny gas bubbles produced by the yeast, causing the expansion. Without this action, bread dough would end up as a dense blob, like building material.

The more times this process is repeated, the lighter and fluffier the finished product will be. Once this ball of gas-filled-gluten is heated, it turns into the tasty treats we all enjoy, whether it be bread, rolls, or any number of other baked goods.

Yeast’s downside is that it takes time to work. There are faster options. One of those is baking soda, or sodium bicarbonate. It reacts to liquid acidic ingredients such as vinegar or lemon juice to produce carbon dioxide. When you add a little vinegar to baking soda, the fizz that you hear is this reaction. Just like when using yeast, the carbon dioxide bubbles that are formed causes the rise in baked goods.

The good news is that this reaction is fast, you do not have to wait for the dough to rise like when using yeast. The downside is that foods containing baking soda must be baked immediately, because if the batter is allowed to set even 30 minutes then the gas will be lost while it sets and the end product will be dense with gummy centers instead of light and fluffy. Baking soda adds flavor and color by hastening the browning.

The third choice is baking powder, which is really baking soda mixed with a starch and powdered acid. Activating baking powder to produce carbon dioxide requires adding a liquid like water. Most baking powders are double-acting, which means they produce a gas when moisture is added and again when the batter is heated. So, baked goods leavened with baking powder tend to be lighter and fluffier than those leavened with only baking soda.

Some recipes call for both baking soda and baking powder. When you see both of these listed on the ingredient list, you will also see some sort of acid such as yogurt or brown sugar, used to create the gas. Basically, the reason that both are listed is because more leavening is needed than you have acid available in the recipe. The baking soda is not enough to leaven the volume of batter, so baking powder is added for extra lift. Why not just use more soda? Because using too much baking soda leaves a bad flavor in the final product with not much more lift. Another reason to use both is to create the desired browning and flavor. It’s all about balance.

Now, to make this even more confusing: baking powder can be substituted for baking soda, but not vice versa. Homemade baking powder can be made by combining 1 teaspoon baking soda, 2 teaspoons cream of tartar, and 1 teaspoon corn starch. However, it will not be double-acting, so the batter will have to get to the griddle or oven in a hurry.

Using too much baking powder or baking soda will result in an unpleasant flavor. A good rule of thumb is to use 1/4 teaspoon of baking powder or baking soda for each cup of flour.

Even after learning these basics, there is nothing more maddening than preparing a recipe with any of these agents and having the dessert fail because the leavening was too old or had gone bad. It is always best to check the freshness of these products before adding them to the batter. For yeast, add a teaspoon of sugar to the yeast in a little warm water, and if it starts to bubble and “grow,” it is good. To test baking powder, put 1.2 teaspoon baking powder in 3 tablespoons of warm water. Stir it slightly and you should see it fizz. As for baking soda, add 1/2 teaspoon to 3 tablespoons of white vinegar and watch for the fizz.

Baking is one of my favorite pastimes. Knowing which leavening agent works best for which product will help me to not waste time and ingredients. With the Christmas baking season straight ahead, I'm on to better baking!

Yeast
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