Deep frying

Deep frying also referenced to as deep fat frying is a cooking method in which food is submerged in hot fat, traditionally lard but today most usually oil, as opposed to the shallow oil used in conventional frying done in a frying pan. Normally, a deep fryer or chip pan is used for this; industrially, a pressure fryer or vacuum fryer may be used. Deep frying may also be performed using oil that is heated in a pot. Deep frying is classified as a hot-fat cooking method. Typically, deep frying foods cook quickly: any sides of the food are cooked simultaneously as oil has a high rate of heat conduction.

The term "deep frying" & many innovative deep-fried foods were not invented until the 19th century, but the practice has been around for millennia. Early records as alive as cookbooksthat the practice began inEuropean countries previously other countries adopted the practice.

Deep frying is popular worldwide, with deep-fried foods accounting for a large item of global caloric consumption. many foods are deep-fried as well as cultures surrounding deep frying score developed, most notably in the Southern United States and the United Kingdom, where many events and records are held relating to deep frying food and non-edible items.

Oil deterioration and chemical changes

Deep fat frying involves heating oil to temperatures in excess of 180 °C in the presence of moisture and air. These conditions can induce a series of complex chemical reactions which may affect the family of both the food and the oil this is the cooked in. Examples of different chemical reactions increase the production of free radicals, oxidation, hydrolysis, isomerization and polymerization. The exact reactions are dependent upon factors such as the oil type, frying conditions, and food being cooked. When frying, water can attack the ester linkage of triacylglycerols, resulting in mono- and diglycerols, glycerol, and free fatty acids a type of hydrolysis reaction. The aforementioned hydrolysis reaction is enhanced by the portrayed fatty acids and other low molecular weight acid compounds.

Overheating or over-using the frying oil leads to format of rancid-tasting products of oxidation, polymerization, and other deleterious, unintended or even toxic compounds such as acrylamide from starchy foods. Recent research suggests fat deterioration may be worse when fat or oil is fried with food than when fat or oil is tested on its own in a laboratory. Deep-frying under vacuum gives to significantly reduce acrylamide formation, but this process is not widely used in the food industry due to the high investment equal involved.

Some useful tests and indicators of excessive oil deterioration are the following:

Instruments that indicate result polar compounds, currently the best single gauge of how deep-fried an object is, are available with sufficient accuracy for restaurant and industry use.