Food Science Basics
Cooking can be fun if you think of all the science experiments that go on in your kitchen.
As a kid, you may have added baking soda to a bottle of vinegar and watched bubbles pour over; this is similar to what happens when baking soda is added to muffin, pancake or biscuit batter.
Understanding a little food science can help improve the results of your recipes…and can be fun!
Some basic terms to keep in your kitchen toolbox:
Caramelization is a technique to brown foods and add flavor using sugar. Carmelization occurs when sugar is heated until its molecules begin to break apart and form small fragments of sweet flavored compounds. The sugar can be added sugar or the natural sugar in fruits and vegetables. This is why bitter vegetables like turnips (which contain starches – or sugars) turn sweet when roasted.
Gelatinization is when a liquid turns into a gelatin or jelly. Protein or carbohydrate/starch helps get a liquid to this point.
Protein – When meat, chicken or fish broth cools, it becomes a fragile solid because the protein molecules attach to each other, trapping liquid. This is also how gelatin desserts (like Jello®) are formed.
Starches like flour and rice, absorb liquid and swell. Eventually, the starch molecules get so big, they leak and thicken the liquid. Examples include white sauce made with flour, fruit sauces made with cornstarch, arrowroot starch, or tapioca.
Denaturation is the process of changing part of the protein’s natural structure by a chemical or physical reaction. Using heat when cooking is a great example of denaturation. Cooking heat breaks down the toughness of meat to make it edible, but doesn’t destroy most of the nutrients found in meat.
Another great example is eggs. Heat lengthens egg protein molecules until they bond and stick together (also known as coagulation). With enough heat and time, this continuous network of stuck-together proteins, along with little pockets of water in between, helps form the sturdy consistency that is important for recipes like custard.
Emulsification results when two liquids that don’t normally dissolve together – like oil and water – are combined. Oil and water (or vinegar) can be emulsified by mixing but eventually, they will still separate unless you add a binding food.
For example, to successfully mix or emulsify a vinaigrette salad dressing of oil and vinegar, add a binder or emulsifier like some mustard powder mixing slowly at first and then vigorously with a whisk or fork.
Source: McGee, H. (2004). On Food and Cooking: The Science and Lore of the Kitchen. New York: Scribner.
Article copyright © 2012 American Heart Association. This article is brought to you by the American Heart Association’s Simple Cooking with Heart Program. For more articles and simple, quick and affordable recipes, visit heart.org/simplecooking.