Where there’s smoke…

Plenty of recipe writers will tell you to make sure you don’t heat an oil past its smoke point, or dire consequences will occur. This raises the dual questions of what kind of consequences and how bad are they? The answers are complex, says Becky Krystal at The Washington Post. She explains the ins and outs of smoke points in various fats.

All oils and other fats have a certain temperature at which they will make smoke. This temperature varies not only on the type of fat, but even within types. For example, olive oil’s smoke point can be affected by the variety of olives used, how refined the oil is, and even the weather during the growing season, according to Joseph Provost, a chemistry professor who co-wrote a book on the science of cooking.

So what bad things will happen if you exceed this temperature? Besides a kitchen full of smoke, the oil can form compounds that have been found to be carcinogenic, but unless you work in a kitchen and are exposed to this frequently, that is not likely to be a a huge concern. A bigger risk for home cooks is the potential for exceeding the smoke point and reaching the flash point, which is when the oil or fat will catch on fire.

Animal fats tend to have lower smoke points than vegetable fats, and there is a huge range in the smoke point temperatures in those as well. The article lists the approximate smoke point for each type of common cooking oil or fat. You are more likely to reach the smoke point when you are working with relatively little oil over direct heat, like when searing meats. When using the oven, the smoke point isn’t as critical because there are other things to absorb the heat and because whatever you are cooking is not likely to actually reach the setpoint of the oven – if it does, your food is likely burnt by that time.