Cooking began as a very pragmatic ritual. It’s what made our food tastier, not to mention easier to chew. Over time, it has maintained its pragmatic value but has also gained a deep cultural significance. You can learn a lot about a culture by exploring its cuisine and sharing food to strengthen social ties throughout the world. We all like to show off our cooking skills (if we have them) and we celebrate most special occasions by sharing a meal with family and friends. Most religious also include some sort of dietary guidelines. 

Cooking is much more than a way to make food more palatable. It’s an important aspect of the human experience. So join us in taking a peek behind the scenes and learn more about the chemistry of cooking. 

What Is Cooking?

We’ve established the cultural value of cooking, but what is it, really? Well, to put it simply, cooking is any process that makes food suitable for eating. The methods used tend to vary widely since they’ve usually been developed as a way for people to adapt to the demands of their environment. For example, pickling is a way to preserve certain foods like vegetables for much longer so people could stock up on supplies for times when they’re scarce, such as winter. 

However, when most people think of cooking, they usually think about using heat to prepare food, which we’ll focus on in this article. 

Cooking Is Chemistry

Now let’s find out why taking some chemistry classes can help you become really good at cooking. Although people say that cooking is an art, which is in part true, there’s also a fair amount of science behind it. And that’s because cooking is chemistry. Every time you go into your kitchen, it’s a bit like entering a lab with supplies and gear. 

Recipes are written documentation with measurements and instruction that, when understood and correctly followed, should lead to a specific and repeatable outcome. You take a series of ingredients, combine them, and apply heat or cold with the purpose of getting a delicious (and hopefully healthy) result. 

That result depends on some chemical reactions taking place. For example, when you heat sugar so it turns into syrup or you add corn syrup to get to the final product, which is caramel – those are all the result of chemical reactions. 

Once you understand how these processes work, you can use them to your advantage. You’ll also gain more flexibility in the kitchen. You’ll no longer have to follow the recipe to a T because you’ll know how what chemical reactions need to take place and how to get to them. 

Carbohydrates

In recent years, this word has begun to strike fear in the hearts of many but let’s see what carbs really are. In terms of chemical structure, carbs are molecules that contain carbon, oxygen, and hydrogen. The ratio between oxygen and hydrogen is typically 2:1, the same as water. Carbs are essentially sugars and starches. Starches are also sugars, but they have longer molecules. 

Earlier in this article, we mentioned heating sugar. If you heat table sugar or sucrose, which is a carb, you probably noticed that it starts to brown, turn into liquid, and bubble. The bubbling that you see is the result of hydrogen and oxygen forming water molecules and evaporating. The browning is the result of polymerization, and the smell stems from volatile substances such as diacetyl released during pyrolysis. 

This process of caramelization is also key in preparing plant-based foods. If you cook vegetables in a stir-fry on high heat, the starches and sugars will start to break down and caramelize, so you’ll notice some browning as a result. 

Caramelization is likewise part of the reason why baked goods have that appealing golden-brown hue. Another reason is the Maillard reaction, also a form of heat-powered browning but at lower temperatures. The name comes from the French chemist Louis-Camille Maillard who first described it in 1912. It’s a reaction between amino acids and reducing sugars. 

Acids and Bases 

Although the word acid sounds scary (but still not as scary as carbs), you have many of them in your kitchen. For example, Coca-Cola has a pH value of around 3.2. Just to clarify, 7 is neutral, and the lower the value, the more acidic it is. As with many other soft drinks, Coca-Cola contains phosphoric acid, which gives it that tangy flavor and keeps bacteria and mold from multiplying inside the sugary mixture. 

The human stomach also contains phosphoric acid as well as hydrochloric acid, an acid with a lower pH value. Although we’ve seen many YouTube videos where Coca-Cola is used to remove rust from metal, and this makes it seem like it’s very strong, it actually has a similar acidic pH value to oranges or apples. Lemon juice is much more acidic with a pH of about 2.

The opposite of an acid, chemically speaking, is a base. Bases are substances with a pH value of more than 7. A common example found in the kitchen is baking soda. 

Lipids 

Lipids are commonly referred to as fats. A fat molecule is made of two main components – fatty acids and glycerol. Glycerol is a simple trihydric alcohol with three hydroxyl groups, three carbon atoms, and five hydrogens. Fatty acids have long hydrocarbon chains to which a carboxyl group is attached. Most commonly, the number of carbon is between 12 and 18, but it can contain 4 to 36. Most dietary fats are triglycerides that contain 16, 18, or 20 carbons.

The chemistry is a bit complicated, but the longer the chains, the more jumbled up these compounds are, which is why fats are usually solid at room temperature. Oils are an obvious exception to this rule since they’re made of short-chained fats. When you apply heat to fats, these chains start to slide past each other, and you see the fat becoming liquid. 

Since fats have high energetic value and they’re the densest form of energy our bodies can store, you’re inclined to find fatty foods delicious and seek them out. This is also why fat is used to give food more flavor. We fry food and add butter to sweets. 

Having said that, you’re probably aware that too much fat is not good for your health, especially saturated fats that have more hydrogen atoms and can pack more energy, and more energy means more calories. Animal fats tend to contain more saturated fats. Plant-based fats have more unsaturated fats, which have a double bond and less hydrogen and therefore pack fewer calories.