Which oil should I use for frying?
When choosing oil for frying food refined oils should be used. Refined oils are less contaminated and provide food with a neutral taste and smell. These refined oils have removed potentially harmful compounds which could be created under the influence of high heat. Examples of such oils are canola oil, soybean oil and sunflower oil.
Do not use cold-pressed oil: You should not fry food in cold-pressed oils. Cold pressed oils such as extra virgin olive oil contain a variety of compounds that give flavor and character. However, the extra flavor and smell of cold pressed oils may adversely affect the food in which it is used. In addition such oils have inferior baking properties causing extra spatter from the pan. At high temperatures, the various ingredients of cold pressed oils decompose and form compounds which may also be harmful in large quantities. Cold pressed oils are therefore better suited in dressings and marinades.
Temperature: Oils for frying are supposed to transfer heat to food and contribute to positive taste and smell of the product. Hence, frying oils should be thermally stable and not decompose under heat. One should preferably not sauté or fry at a temperature higher than 180 ° C because the oils will decompose into potentially harmful substances.
Wash the frying pan: Generally speaking, the more polyunsaturated the oil is, the more it is prone to oxidation and subsequent decomposition. Frying should take place over a relatively short time so that the oil is changed as little as possible. Use of a greasy pan from previous frying will promptly initiate oxidation of new oil. Therefore be careful to wash the frying pan after use.
Safe products:Food Safety Authorities (FSA) have previously analyzed many vegetable oils – both cold pressed and refined – in the Norwegian market for the carcinogenic substance (PAH) but found generally very low levels. Some time ago, producers from Mediterranean countries used methods that could have resulted in unacceptably high concentrations of PAHs in different types of vegetable oils. Since then, Norway has established regulations which limit PHA’s, and the FSA considers these products in general as safe.
Conclusion: Oil to be used for cooking food should be clean and free of harmful substances. Therefore, tasteless, refined oil is best suited for frying.
Source: Norwegian Food Safety Authority