As it turns out, this is a trick question! No two cooking oils are created equal — each one has their own nutritional advantages and best uses in cooking. For this reason, it’s beneficial to not just have one but several oils in your pantry. The key is in knowing when to use which one!
Extra virgin olive and nut and seed oils (such as walnut, hazelnut, flaxseed and sesame) have vivid and unique flavor profiles that can add interest to salad dressings and dips. They’re also great for drizzling over finished dishes. Unfortunately they’re not ideal for cooking. Heating these oils can break down the volatile compounds that give them their characteristic aroma and flavor. It also destroys delicate phenols, flavonoids and other antioxidant compounds. You’ll get the most flavor and nutrition by reserving these oils for off-heat uses.
Storage tip: Olive and avocado oils can be stored at room temperature, but nut and seed oils are best kept in the fridge.
For sautéing, roasting and stir-frying, you want oils that have a high smoke point — for obvious reasons! But smoke point is only one consideration. You also want to choose oils that are low in polyunsaturated fats because heating these fats to high temperatures creates harmful compounds called 4-hydroxy-trans-2-nonenal or HNEs.
Unlike smoke, which you can see and smell, HNEs are invisible and tasteless. Nonetheless, they can damage cells, cause inflammation and may contribute to the risk of cancer and other diseases. Ironically, many of the oils that you’ll see recommended for high-heat cooking (think: corn, soybean, peanut oils) because of their high smoke points are quite high in polyunsaturated fats and therefore more likely to form HNEs when heated.
The best choices for high heat sautéing and frying are oils that have a high smoke point but are low in polyunsaturated fats. These would include filtered or “light” olive oil — which is mostly monounsaturated fat — along with clarified butter (ghee), refined coconut and palm oil, which are rich in saturated fats.
Although we tend to think of “refined” as a bad thing, refining an oil simply means filtering out natural plant compounds present in unrefined oils. Although the phytocompounds in extra-virgin oils add flavor and nutritional benefits, they also lower the smoke point. That’s why refined oils are sometimes labeled as being for high heat.
What oil do you use for high heat cooking? Share your thoughts in the comments below.