Deep frying requires oil to be heated to high temperatures in excess of 149 degrees Celsius. To choose an oil for frying, you must know its smoke point. The smoke point is the temperature the oil begins smoking. Heating the oil beyond the smoke point to the flash point results in ignition of the oil. Each time you reuse oil, the smoke and flash points decrease by up to 37.8 degrees Celsius. Choosing vegetable oils with the highest initial smoke points will prevent the oil from smoking with subsequent uses.
Peanuts grow in the ground and are botanically considered legumes. Peanut oil could therefore be considered a vegetable oil instead of a nut oil as it does not come from a tree nut. Peanut oil is readily available in gallon-sized and larger containers at supermarkets and camping stores. This is the oil of choice for deep frying turkeys. It has a mild taste and a high smoke point of 232 degrees Celsius. This oil can be used with all deep frying applications. The oil itself, though consists of 17 per cent saturated fat.
Like peanut oil, safflower oil has a high smoke point of 232 degrees Celsius. This oil does not impart any flavour on the food, and it contains less saturated fat than other vegetable oils. Safflower oil contains 9 per cent saturated fat. Do not confuse safflower oil with sunflower oil. Sunflower oil has a much lower smoke point of 199 degrees Celsius. Keep safflower oil in the refrigerator and eat products fried in it immediately to avoid the rapid rate this oil breaks down to create rancid flavours and odours, warns Shirley O'Corriher in "Cookwise."
Soybean oil might be difficult to find, but if you do locate it with the other oils in gourmet grocery stores, health food stores or on the Internet, get it for deep frying. This oil contains 14 per cent saturated fat, and it has a smoke point of 232 degrees Celsius. It's light colour and flavour do not significantly alter the flavour of foods cooked in it.
Canola is the name given to a strain of low erucic acid rapeseed oil. This vegetable oil is easily found in supermarkets. It has a high smoke point of 225 degrees Celsius. Though canola has a slightly lower smoke point than other oils, its availability makes it one of the best deep frying oil options. "The Food Substitutions Bible" notes that canola has no flavour and a low 6 per cent saturated fat content. Shriley O'Corriher notes that though canola has no natural flavour, deep frying lightly flavoured foods might result in the diner detecting slight beanlike overtone from the canola. This taste will be undetectable in most seasoned fried foods.