Why does animal fat taste so much better than plant-based fats in certain cooking applications?
In our recipe for Duck Fat–Roasted Potatoes (see related content), roasting our spuds in animal fat instead of olive oil gives them much richer flavor. But why does animal fat taste so much better? It has to do with the fatty acids that give any fat its particular flavor profile. In refined oils such as pure olive oil, many of the volatile fatty acids and aroma compounds have been stripped away to make a neutral tasting oil that will work in a variety of applications. Meanwhile, unrefined oils like extra-virgin olive oil have plenty of flavor, but because some of their volatile fatty acids and aroma compounds evaporate when exposed to heat, they lose most of it after a few minutes of cooking. But when the fatty acids in an unrefined animal fat are exposed to heat, they oxidize to form new flavor compounds that actually improve flavor and make it taste more complex.
Animal fats can deepen the flavor of lots of foods beyond our potatoes. Try bacon fat instead of butter on the bread for a grilled cheese sandwich, or use it to sauté greens like kale or collards. Substitute the animal fat of your choice for the oil in fried eggs or roasted Brussels sprouts. Chicken fat is a great substitute for the butter in rice pilaf.