What happens to the fats when oily fish is seared or fried at high temperatures?

The fats can begin to oxidize, reducing health benefits and creating off-flavors.

The method used to prepare oily fish significantly impacts the integrity and nutritional value of its beneficial fats. While omega-3 fats possess a degree of stability compared to certain other fats, subjecting them to extreme heat, such as during searing or prolonged frying, initiates a process called oxidation. Oxidation degrades the delicate fatty acids, diminishing their recognized health advantages, such as anti-inflammatory effects. Furthermore, this process can lead to the formation of undesirable compounds that result in noticeable off-flavors in the cooked product. Gentle preparation techniques like baking, grilling, poaching, or steaming are advised to preserve the fatty acid profile optimally.