John Myers
Can vegetable oil be used for longer frying at high temperatures? When can I use olive oil for frying? It mustn’t get too hot. Searing meat doesn’t work then – or does it? What can I fry with margarine?
The use of fats and oils depends on the type of preparation.
High-quality vegetable oils are particularly suitable for cold dishes such as salads. They have a high content of polyunsaturated fatty acids, which are essential for the body. They also contain fat-soluble vitamins, phytochemicals and have an intense aroma.
Examples are linseed oil, walnut oil or rapeseed oil. These oils should be virgin and cold-pressed, not refined.
It is precisely the polyunsaturated fatty acids that greatly limit the use of vegetable oils in the kitchen. They are destroyed by heat, too much oxygen and light. Decomposition products that are harmful to health can also form if the temperatures are too high. For this reason, most vegetable oils are not suitable for searing meat.
Oils and fats that have a high smoke point can withstand higher temperatures. The more saturated or monounsaturated fatty acids (such as oleic acid) the fats contain, the higher the smoke point.
Olive oil is about 75% oleic acid and 10-15% saturated fat. This means that it can be heated up to 180 °C and used for gentle roasting or deep-frying. But you should keep in mind that when searing meat in a pan or when cooking it in a wok, higher temperatures can be reached quickly.
Rapeseed oil should be used in a similar way to olive oil, as it also has a very high proportion of oleic acid at 60%.
So-called high-oleic oils, which are also available in organic stores, are another option for frying. These are oils from special types of sunflower, rapeseed and thistle, which have been cultivated to have a higher oleic acid content. They are cold-pressed, but can withstand temperatures of up to 210 °C.
Coconut fat, palm oil and palm kernel fat can also withstand high temperatures. These fats naturally have a very high proportion of saturated fatty acids and are therefore solid.
However, coconut and palm kernel fat and palm oil are not particularly recommended for ecological reasons due to the intensive processing, cultivation and very long transport routes.
Butter and margarine are not suitable for frying because they have a very high water content. It is different with clarified butter, which consists of up to 99.8% pure butterfat. However, the temperatures should not get much higher than about 170 °C.
For further reading:
Edible oils – which ones are suitable for what?
