"In cooking, the smoke point of an oil or fat is the temperature at which, under defined conditions, enough volatile compounds emerge from the oil that a bluish smoke becomes clearly visible. At this temperature, volatile compounds, such as water, free fatty acids, and short-chain degradation products of oxidation come up from the oil. The smoke point is the temperature at which the oil is decomposed and where possibly toxicological relevant compounds are formed.
The smoke point for an oil varies widely depending on origin and refinement. The smoke point of an oil does tend to increase as free fatty acid content decreases and degree of refinement increases.Heating the oil produces free fatty acid and as this heating time increases, more free fatty acids are produced, thereby decreasing smoke point. It is one reason not to use the same oil to deep fry more than twice.Intermittent frying has a markedly greater effect on oil deterioration than continuous frying.
Considerably above the temperature of the smoke point is the flash point, the point at which the vapours from the oil can first ignite when mixed with air."
See the smoke points for oils such as Olive, hemp,etc.
- stay away from oils such as butter, ghee,lard and any other animal derived oils.