Chemistry can be found all around, with one unique place being in the kitchen. Just like in a laboratory, baking is a delicate recipe of chemical reactions where the right combination of ingredients can yield tasty results.
There are four essential components in baking: proteins (amino acids), lipids, carbohydrates, and water. These ingredients interact in complex ways that create different textures and flavors. Understanding the chemistry behind these interactions can elevate baking.
Each time flour, sugar, and eggs are mixed together, it’s not just following a recipe. The recipe is a scientific process that transforms raw ingredients into baked goods, and while this process can be complex, it also allows for the creativity to experiment with flavors and textures.
“Baking, especially pastry type baking, definitely has chemical reactions that are changing ingredients in the recipe to products,” Chemistry teacher Paul Birkenfeld said.
The most important chemical reactions that happen in the kitchen are from sodium bicarbonate and sodium hydrogen carbonate. These compounds are more commonly known in the kitchen as baking soda and baking powder.
“Baking soda is a quick leavener,” Food and Nutrition teacher Alicia Flint said. “So, when you add that to a baked good, it does have a chemical reaction in the oven with the addition of a liquid and mixing it around.”
Even though baking powder sounds similar to baking soda, they do very different things and produce different results. Baking powder releases carbon dioxide twice during baking, unlike baking soda. Carbon dioxide is released once when mixed with liquid and once more when in the oven.
“Knowing if I don’t have this, but I do have this, you can substitute something, but you have to understand what it’s going to do to your food first, before you make any changes,” Flint said. “If you change one thing, you’re probably going to have to change something else, and that includes ingredients.”
Another key reaction that happens is the Maillard reaction. The Maillard reaction is the chemical reaction between amino acids, sugar, and heat to create a browning effect. This happens in almost all baked goods like cookies, pastries, and bread.
“Steak browns when you cook it, cookies get a little bit browner, they turn a different color and they caramelize,” Flint said. “It’s called the Maillard reaction.”
While the science of baking can be complex, it doesn’t take being a professional to explore these reactions. One way to get into chemistry that’s not baking is an at-home science kit, which offers a safe and controlled environment without the risk of creating toxic reactions. A brand called KiwiCo is a great option because they have a variety of different kits for all age ranges.
KiwiCo also has a blog that covers topics like the science behind their kits. One of their posts discusses the chemical reaction in baking a cake, giving detailed information about proteins, baking powder, and aqueous solutions, which further ties in with their very popular Science of Cooking: Mini Cakes kit.
“Especially at home, don’t ever just start mixing things, because there are things you could mix at home that will create products that are toxic,” said Birkenfeld. “I wouldn’t just start randomly. I would suggest checking out resources from reputable resources.”
Chemistry can be dangerous, so that means baking can too; it is important to read the recipe well and make sure everything goes right. While some things may be okay to adjust, like the amount of chocolate chips in a cookie, it is important not to adjust other ingredients like baking powder, baking soda, and flour.
“I definitely agree that baking is the science part of cooking because you have to measure exactly,” Central Kitsap Middle School Food Science teacher Laura Cherry said. “It can throw off your quantities and make things rise too much and with too high of heat, it’s going to burn.”
Too much of a reaction is not good, and too little is just as bad, but the right amount can make a fluffy treat. If there is too much leavener it will get too fluffy and overflow, but if there is too little, it will get hard and dense.
“If you don’t put in the baking soda, you don’t get what you were planning on,” Central Kitsap High School Chemistry teacher Ken Henrichsen said. “When baking soda breaks apart you get some carbon dioxide that makes the biscuits a little fluffier. If you leave the baking soda out it’s going to be a dense lump of bread.”
While baking might seem fun and simple, there is a more complex transformation happening every step of the way. The ingredients go into the oven and come out completely transformed. They come out with a different texture, look, and smell.
“In baking, you mix ingredients together, and all of those ingredients are chemicals, because they’re all made out of atoms,” Henrichsen said. “When you mix them together in the right proportions and put them in the oven to heat it up, it comes out chemically different than what it started as. We were watching a video this morning on cookies, and it is not just flour, water, and egg. Those ingredients have changed chemically and rebounded in other ways.”
Baking may feel like an art, but it is truly a science. Every recipe is an experiment, and understanding the reaction behind it can be the distance between a failed dessert and a perfect batch of cookies. No matter the person, a home baker or a science enthusiast, there is always more to discover about the chemistry happening in the kitchen.
