Though the history of deep frying is ancient, the term "deep frying" and many modern deep-fried foods were not invented until the 19th century, but the practice has been around for millennia. Early records and cookbooks suggest that the practice began in certain European countries before other countries adopted the practice (such as Portugal).

Deep frying is popular worldwide, with deep-fried foods accounting for a large portion of global caloric consumption. It should be noted that though the process of deep frying is ancient, the English expression 'deep-fried' is only attested from the early 20th century.

Deep Frying, A History:

Origins and development of Deep Frying

Deep-fried bread dough is known from Egyptian paintings dating to at least the 1st millennium BCE and a similar confection, known as Zalabiyeh was eaten as early as the late 2nd millennium BCE in Canaan. Frying food in olive oil is attested in Classical Greece and was practiced in Classical Rome at least by the 1st century CE. Deep frying has been a part of Chinese cookery for at least 3000 years.

The practice of deep frying spread to other parts of Europe and America in the following centuries. Deep-fried foods such as funnel cakes arrived in northern Europe by the 13th century, and deep-fried fish recipes have been found in cookbooks in Spain and Portugal at around the same time. Falafel arrived in the Middle East from Egypt as early as the 14th century.

French fries (chips), invented in the late 18th century, became popular in the early 19th century western Europe. In 1860, Joseph Malin combined deep fried fish with chips (french fries) to open the first fish and chip shop in London.

Deep frying food is defined as a process where food is completely submerged in hot oil at temperatures typically between 177°C and 190°C, but deep frying oil can reach temperatures of over 205°C. One common method for preparing food for deep frying involves adding multiple layers of batter around the food, such as cornmeal, flour, or tempura; breadcrumbs may also be used.

While most foods need batter coatings for protection, it is not as necessary for cooked noodles and potatoes because their high starch content enables them to hold more moisture and resist shrinking. Meats may be cooked before deep frying to ensure that they are done inside while keeping juiciness.

When performed properly, deep frying does not make food excessively greasy, as the moisture (water) in the food repels the oil. The hot oil heats the water within the food, steaming it; oil cannot go against the direction of this powerful flow because (due to its high temperature) the water vapour pushes the bubbles toward the surface. As long as the oil is hot enough (177–191°C) and the food is not immersed in the oil for too long, oil penetration will be confined to the outer surface. Foods deep-fried at proper temperatures typically absorb only a couple of tablespoons per 625ml of oil used. This oil absorption rate is around the same as occurs with shallow frying, such as in a pan. Though it should be noted that the surface area of the food also plays a part. So, skinny fries will absorb more fat than chunky chips per gram of food cooked. If the food is cooked in the oil for too long, much of the water will be lost and the oil will begin to penetrate the food.

Deep frying is done with an electric deep fryer, a pan such as a wok or chip pan, or a cast-iron pot (Dutch oven). Additional tools include fry baskets, which are used to contain foods in a deep fryer and to strain foods when removed from the oil, and cooking thermometers, used to gauge oil temperature. Tongs, slotted spoons, wooden spoons, and sieves may be used to remove or separate foods from the hot oil. It is recommended that deep fryers be cleaned often to prevent contamination. The process of cooking with oil can also contaminate nearby surfaces as oil may splatter on adjacent areas.

Classic Deep Fried Dishes

Africa In Northern Africa, deep-fried dishes are a part of the cuisine. A common food in this region is the deep-fried fritter, also referred to as 'sponges'. Bean-based fritters, such as banana akara are common in West Africa, as are deep fried plantain chips. In East Africa deep fried food is common, cooked in cast iron or earthenware pots. Frying in batter is common. A Ugandan specialty is a kind of doughnut called Mandazi. In areas of Southern Africa, street foods include deep-fried potato and cassava chips. Deep-fried foods in South Africa include fish and chips, vetkoek and koeksisters, among others.

Asia Peixinhos da horta is a traditional dish in Portuguese cuisine. The name of the dish is literally translated as 'Little Fish from the Vegetable Garden', as it resembles small pieces of colourful fish. It was introduced to Japan by Portuguese sailors Antonio da Mota, Francisco Zeimoto and Antonio Peixoto in the sixteenth century, where it was eventually developed into tempura. Japanese deep-fried dishes, or Agemono, include other styles besides tempura, such as Karaage, Korokke, Kushikatsu, and Tonkatsu.

In areas of Southeast Asia such as Thailand, insects are commonly deep-fried for human consumption. Western-style fast food items such as donuts, deep-fried chicken, and deep-fried potatoes are also becoming popular in Asia.

In Indonesia deep fried food is quite common, serving as either a main dish or a snack. The ingredients are usually deep fried in palm oil, the most widely used cooking oil in the country. Some popular deep fried foods include ayam goreng (chicken), pecel lele (catfish), pempek (fishcake) and tempeh.[44] Fritters in Indonesia is generally identified as gorengan, the most popular one including pisang goreng (banana fritter), bakwan jagung (corn) and tahu goreng (tofu).

Deep-fried fish, tofu, and chả giò are commonly eaten in Vietnamese cuisine. Deep frying is also used to make several kinds of bánh, including bánh rán (fried rice ball), bánh cam (sesame ball), bánh tiêu (hollow doughnut), bánh rế (sweet potato pancake), bánh chuối chiên (banana fritter), Hồ Tây–style bánh tôm (shrimp fritter), and bánh gối (pillow cake).

Indian cuisine has a number of deep-fried dishes, including samosas, jalebis, bhajis and pakoras.

Europe Northern European countries tend to use pure or hydrogenated rapeseed oil for deep-frying. Mediterranean diets traditionally use olive oil for deep-frying, which it is absorbed by the food in the process. Research indicates that virgin olive oil is unique among other cooking oils because it is very rich in monounsaturated fatty acids and contains beneficial micronutrients. Fried dishes include starters, main meals, desserts, sweet dishes and starters.

The Americas in the United States, soybean oil is often used for deep-frying. Beignets, originally a French dish, are a popular deep-fried pastry in the U.S. city of New Orleans. Deep-fried food has been a core part of the culture of the American South with many restaurants solely serving deep-fried foods. The owner of one such restaurant has said of deep-fried food that ?in the South it's a way of life'

The buñuelo, a fried dough ball popular in Central America and Greece, is a popular deep-fried snack and street food in South America.[28] Picarone, a Peruvian dessert originated in the colonial period, are deep-fried doughs made with pumpkin and sweet potatoes, popular in Peru and Chile, especially during harvest festivals.,[60] a family of deep fried cakes is well known across, sopaipillas a Chilean bread are deep fried in oil or butter also made with pumpkin, Chancay a Peruvian bread made of flour, salt and yeast, known as chipá cuerito in Paraguay and Torta frita in Argentina and Uruguay, made of flour, salt and yeast, sometimes addition with milk and animal fat and fried in cow fat, the churro, a fried dough popular in Spain is a popular fried snack and street food in Argentina and Uruguay