Frying

Frying is a way of cooking food by using oil or fat. It is similar to sautéing, but when frying, the food is usually turned over once or twice with tongs or a spatula to cook it evenly. Many different kinds of foods can be fried, from chicken to potatoes.

During frying, important changes happen to the food. The heat and oil cause proteins to change shape, starches to swell, the surface to brown, water to evaporate quickly, and oil to be absorbed into the food. This makes frying not just a way to cook, but also a process that removes water and changes the food in many ways.

History

Frying is thought to have started in Ancient Egyptian cuisine around 2500 BC during the Old Kingdom. Evidence shows that people in India were frying food with ghee around 1500 BC. In China, an old book called the Book of Rites describes a recipe for fried rice from the Zhou dynasty. Frying pans were found in grave goods in Norway from the seventh century. Later, famous stories like the Wife of Bath's Tale and Don Quixote mentioned fried foods such as fried eggs.

Process

When food touches oil that is very hot (between 150–200 °C or 302–392 °F), interesting things happen. The water inside the food turns into steam, making the food absorb some of the oil. This creates small holes in the food.

The outside of the food gets crispy and brown because of special chemical changes. The inside of the food gets softer while the outside stays crisp. Frying is done when all the water inside the food turns to steam. When the food cools down a little, the steam inside turns back into water, and this helps more oil get inside the food.

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Techniques

Deep frying

Main article: Deep frying

In deep frying, food is put into very hot oil or fat so that it cooks all over at once. You can use a deep fryer or a chip pan, or for big cooking jobs, a pressure fryer or vacuum fryer. Sometimes food is covered in a special mixture or breading before frying to give it color and a crispy surface. Popular deep-fried foods include French fries, doughnuts, cong you bing, and tempura.

Sautéing

In sautéing, food is moved around quickly over high heat in a frying pan with just a little oil to stop it from sticking. A sauté pan, which has higher sides to keep food in while it moves, can also be used.

Shallow frying

In shallow frying, also called pan frying, food is cooked in a small amount of oil on one side until it turns brown, then turned over to cook the other side.

Stir frying

Main article: Stir frying

Stir frying is a Chinese way of cooking using a hot wok. The ingredients are stirred constantly so they cook evenly. The bottom of the wok is placed right in the fire, and its shape lets the flames go all around it. Stir frying is done quickly, in just two to three minutes.

Health effects

Eating a lot of fried food can be bad for your health. Studies have shown that people who eat the most fried foods have a higher chance of having heart problems, like heart failure or heart attacks. This is because fried foods often have a lot of unhealthy fats and calories, which can make the body inflamed and lead to other health issues.

Fried foods can also increase the risk of some cancers, like stomach cancer, and may contribute to high blood pressure and obesity. The oil used in frying becomes part of the food, making it very high in fat. Some vitamins in food can be lost during frying because of the high heat, while other parts of the food, like fiber and minerals, can become more concentrated. Breathing in the fumes from frying can also be harmful to the lungs.

Effects of oil

When food is fried, the oil meets water from the food, heat, and air. This can change the oil and the food. Some changes can make the oil less good for cooking and can affect how the food tastes and looks.

Different oils work better for frying than others. Some oils, like olive oil, stay stronger at high heat because they have special parts that help them last longer. Other oils, like sunflower oil, can change more quickly when heated. Reusing oil can also change it, making it taste different and affecting the food’s nutrition. It’s important to watch oil carefully while frying to keep it safe.