I remember the first time I saw my sister-in-law use coconut oil to fry an egg. In my house, coconut oil was used expressly for detangling hair and rubbing into dry winter skin. Technically, yes, I knew it was something one eats, but it felt like I turned around and all of a sudden everyone was telling me to substitute coconut oil wherever I could.
However, that's not a great idea. Coconut oil has a low smoke point, meaning that around 350 degrees it starts to break down, giving food burnt and unpleasant tastes, and even releasing carcinogens. Another oil with a low smoke point? Extra virgin olive oil, which Chef Niki Starr Weyler of Mesa in Costa Mesa, California says too many people try to use for searing. "In order to get a proper sear on proteins, the skillet needs to be on a very high heat, which you just can’t do with olive oil."
Nowadays there seem to be endless oil options at the grocery store. There's vegetable, corn, peanut and canola, but also fancier options like sunflower, grapeseed, coconut, walnut and plenty others. And while it's tempting to just think "oil" and use whichever you want, each has specific qualities that can enhance or derail whatever you’re trying to cook. The general rule, however, is that lighter oils are better for cooking, and darker ones for flavor.
According to Weyler, olive oil of any kind is over utilized. Extra virgin olive oil, which comes from the first pressing of young grapes, is flavorful, dark and expensive. "Extra virgin makes a good finishing oil on top of steak or fish," she says. "To cook or mix with anything because it's so rich in flavor and stands out on its own." Lighter olive oils come from the second or more pressings of olives, but even then, it's poorly suited for high heat cooking. Unfortunately, plenty of recipes call for olive oil when it’s not the best choice, probably because of the connotation that olive oil is healthy. While it's true extra virgin olive oil is full of enzymes and minerals, further pressings don’t have those, and even if they did they break down quickly under heat. Instead, reach for a lighter, neutral flavored oil like vegetable or canola, though Weyler prefers grapeseed. "It has a super high smoke point and imparts little to no flavor while cooking."
Also, beware truffle oil. Chef's hate truffle oil. "I don’t think people realize there isn't actually truffle in it," says Weyler. Instead, it's a combination of a synthetic odorant found in truffles and olive or grapeseed oil. Gordon Ramsay said it's "one of the most pungent, ridiculous ingredients ever known to [this] chef." Joe Bastianich called it "garbage olive oil with perfume added to it." Plenty of blogs point out how the 2-4 dithiapentane, which gives the oil its truffle-like smell, is made with formaldehyde, and use that as proof that it's scary and unnatural. But formaldehyde is also found in our blood, and plenty of foods use flavorings, and I don’t know, I like how a few drops of truffle oil tastes on my pasta. Use it at your own discretion.
If you want to stay away from "synthetics," there are plenty of flavorful finishing oils to be found, from various extra virgin olive oils to walnut oil to sesame oil. They may be expensive, but a little goes a long way. "I suggest people experiment with the different variations that come from various regions because they all produce unique flavors," says Weyler. And if you find yourself with too much, well, you can always detangle your hair.