One important thing to remember when approaching baking is that baking is a science. Unlike cooking, where you can add whatever amount of any spice you want to a recipe, everything you add into a baked good needs to be precise. Otherwise, you'll end up with hockey puck cookies or a hollow loaf of bread. Though it is not vitally important to understand everything about the chemistry that goes into baking, I'll give you the basics rundown.
Let's start with the main ingredient in all baked goods: flour. Most recipes call for all purpose, which is just plain ol' flour without anything added to it. Flour, when combined with water, creates a stretchy, gooey texture due to the gluten in the flour. This gluten helps the bread hold together, and gives it a nice soft texture to the final baked good, like bread. Now, some people can't eat gluten, which means that they can't eat anything with normal flour in it. Back in the day, if you couldn't eat gluten, you were up a creek. No pasta. No bread. NO CAKE. Sounds like a nightmare to me. Thankfully, today we have a variety of different gluten-free flours that can be used for people with celiac disease; almond flour and coconut flour are the two most common. Because these flours don't have gluten, the recipes containing these flours need adjusting, and thankfully, baker's have already figured out what to add to make up for the lack of gluten!
One of my favorite baking websites, Taste of Home, has created an easy guide on making a regular recipe gluten free. One of the options is to make your own gluten free flour, which is made of rice flour, potato starch, tapioca starch, and xanthan gum. The two starches and the xanthum gum, when combined together with water, create a structure similar to gluten so that you get the same soft yet chewy texture that you would have in a recipe with regular flour. Of course, there are also recipes that are made with store bought gluten free flour which makes it so much easier for a beginning baker who doesn't want to try and make their own gluten-free flour, which I personally always just buy the gluten-free flour because I never feel like taking that extra step(Also I'm lazy.)
Next, leavening agents. Not only does the phrase "leavening agents" sound super scientific, it is super scientific! These agents are very important when you're baking for a few reasons; they give all baked products a light and airy texture, it makes the final product super soft, and it keeps the final product from coming out like an actual brick. There are a few different types of leavening agents, including yeast and baking powder.
First, we'll dive into yeast. Yeast is used mostly for breads, as things like baking powder just don't work as well. Yeast is made of tiny microorganisms that eat sugar and, essentially, burp. This gas that is released while the yeast eats up sugar gives bread it's light and soft texture. My favorite brand of yeast(not sponsored I'm just a baking nerd) is Fleischmann's, which is the brand that my mom always used, and I now always use., but any active dry yeast is great. Now, what is active dry yeast? Well, it's yeast that has been dried out and put into a type of hibernation, so that way the yeast can stay good when it is sitting on the shelf before it is used. Then, when you want to use the yeast, you have to bloom it in warm water. Everyday Dishes has an excellent video to show the process of activating this type of yeast, showing you everything from what temperature you want the water to be at, to when you know the yeast is ready to be put into your mixing bowl. One little tip that I have always used is adding a teaspoon of honey to the warm water and yeast mixture. This helps give the yeast a little kick-start since honey is a pure form of sugar that is easily eaten by it.
Baking powder is used more for things like cookies and cakes. I'm sure you've made a volcano in elementary school in which you put baking powder, red food coloring, and vinegar. The result was a huge overflow of red foam that sounded like a fizzy soda being poured. This reaction is because baking soda is more alkaline on the pH scale, and vinegar is more acidic. When the two are combined, they have a mildly violent reaction, which releases tiny gas bubbles as the mixture moves toward a more neutral pH. This same thing happens in baked goods, except on a much smaller scale. Most of the time, only a teaspoon of baking powder is used at a time. This is because we only need a little bit of lift in baked goods, otherwise we'd have cookies that were 5 inches tall and hollow on the inside. This baking soda reacts with the other ingredients, like cocoa powder or buttermilk, to create the reaction needed.
Finally, and the easiest scientific part of baking, is the baking temperature. Almost all baked goods are baked between 325˚-350˚ Fahrenheit, or 163˚-178˚ Celsius for those using the metric system. This small difference in temperature is for one reason: a lower temperature is better for some recipes, and a higher temperature is better for others. Because we want baked goods to be moist and not dried out, we need to ensure it is cooked all the way through without over cooking any part of it. Take cake, it is usually thicker than, say, a cookie. We want the cake to cook all the way through, but we don't want the outside to burn or for the whole cake to end up too dry and crumbly. At a lower temperature, we are able to achieve this, since we have to bake the cake longer than we would bake a cookie.
See, not so scary! The science portion of baking has already been taken care of by the professionals, and we home bakers get to reap the benefits of their hard work. And yes, while you don't need to know the technicalities of baking, it's always good to know how the ingredients work together to get the final product so you know how to adjust a recipe if it doesn't come out just the way you want it to.