Pressure frying is deep-frying under pressure.
It is not a low-fat way of deep-frying, nor a healthier way: it simply speeds up frying time, and so saves on cooking fuel.
It is used primarily for frying chicken under pressure. For instance, Kentucky Fried Chicken (KFC) is cooked in Pressure Fryers. Under pressure, less steam is generated so more moisture remains in the chicken being fried. The food can also be less greasy. Moisture in the food can’t escape because of the pressure, and because it stays there, it prevents oil from coming in and taking its place.
Pressure frying allows for very fast cooking, about 15 minutes for chicken pieces. The food can reach about 250°F (120°C) internally, compared to 215 to 220°F (about 100°C) as occurs with regular frying.
For pressure frying, you CANNOT use a regular pressure cooker. Its rubber seals aren’t meant to withstand the heat of hot oil. You need a designated, certified pressure fryer. Sadly, commercial ones are quite large, and the very few models that are available for home use are quite expensive.
As of 2006, home use models are only being made by the Fagor company in Spain, and by Ultrex. Their models come in various sizes, with pressure release valves. An 8 1/2 quart model will accommodate 8 pieces of chicken at once.
Pressure Fryers are sometimes have been referred to as “Broasters.” This is not quite accurate, unless the pressure fryer has been made by the Broaster company. Many commercial models in North America are made by The Broaster Company of Beloit, Wisconsin.
When Pressure Frying, it is best to use vegetable oils. Otherwise, solid melted fats (shortening, lard) can combine with the steam to give the food a gummy taste.
You fill the Pressure Fryer with about 2 inches (5 cm) of oil, then heat the oil to about 375 F (190 C), then add the food. You fry with the lid off until the food is half done (about 2 to 3 minutes for a piece of chicken), then put the lid on, and screw it down, and continue cooking for another 10 to 12 minutes.
Then, you release the pressure using the pressure valve, and allow steam to escape for 1 minute, then unscrew the lid remove the food. Then, you bring the oil temperature back up, add the food for the next batch and repeat.
Pressure Frying was invented sometime towards the end of the 1930s.
Before Colonel Harland Sanders (Kentucky Fried Chicken founder) switched to pressure-frying, customers often had to wait 30 to 45 minutes for their fried chicken.
The Pressure Fryer that Colonel Sanders first used is displayed at the KFC Restaurant Support Center in Louisville, Kentucky.