What Happens to Carbohydrates & Protein When Cooked?

Protein and carbohydrates are essential parts of a healthy diet. Protein helps supply you with energy and might help you maintain a healthy weight. Carbohydrates are also a source of energy and can supply important vitamins and minerals. Many foods that contain protein or carbohydrates are cooked before you eat them. You might be wondering if the cooking process changes the nutrient content or nutritional value of the food.

Stuffed cooked zucchini and rice. (Image: Sarsmis/iStock/Getty Images)

Protein

Protein is present in every part of your body, including your muscles, bones and skin. Protein is comprised of enzymes that make the chemical reactions possible to carry oxygen throughout your body. The building blocks of protein are amino acids. Your body forms strings of amino acids that help it carry out each function necessary to keep you healthy. Because your body does not make amino acids on its own, it is important to get plenty of protein in your diet each day. Healthy sources of protein include beans, nuts, seeds, legumes, dairy foods and lean meat.

Cooking Process: Protein

Protein goes through certain chemical changes when it is heated and cooked. When the proteins in food are heated, they coagulate, which means they become firm. When exposed to hot temperatures, the protein shrinks and loses moisture. This usually occurs at temperatures between 160 and 185 degrees Fahrenheit. When meat sources of protein are cooked slowly, any connective tissues are likely to dissolve. Heat does not destroy the protein in food, though it might reduce the overall content slightly.

Carbohydrates

Carbohydrates are primarily found in foods with grains, sugars and fiber. Carbohydrates are comprised of sugar molecules, formed when oxygen, hydrogen and carbon fuse together. Each type of carbohydrate is made up of a certain number and pattern of sugar molecules. Simple carbohydrates are foods made with sugars, such as fruit sugar or table sugar. Examples include white bread, white pasta and baked goods. Complex carbohydrates are made when a food contains three or more linked sugars. Complex carbohydrates are healthier than simple carbohydrates, and include oatmeal, whole grains and beans.

Cooking Process: Carbohydrates

There are two possible changes that occur when carbohydrates are cooked. Caramelization occurs when the sugars in the carbohydrates are browned. When bread turns golden brown on top, it is an example of the sugars becoming caramelized. Gelatinization occurs when the starches in carbohydrates absorb water and begin to swell. This chemical change is used to make cooked sauces, breads and other baked goods. When you add certain carbohydrates, such as flour, to liquids, the heat gelatinizes the carbohydrates. This is the process used to make gravy and other thick sauces.