When cooling or reheating food, it’s important to do it right to keep it safe from harmful microorganisms and toxins that can cause food poisoning. Food Safety Practices and General Requirements, food businesses must make sure potentially hazardous food is cooled or reheated quickly so harmful microorganisms don’t get a chance to grow to unsafe levels. Do be aware: reheating fatty fish like salmon and mackerel tends to give off a stronger fishy scent than when it was cooked and served the first time. This is due to the oxidation of its fatty acids which turn into strong-smelling aldehydes, bringing out a more pungent fish aroma.

How to Reheat Fish:

• Microwave: setting it to a very low power mode, 30 to 40 percent of its full power, and microwave in short 30 second spurts until heated all the way through. Flip the fish over every 30 seconds as well to ensure it heats evenly.
• Toaster Oven: Just like a larger oven, a toaster oven will work very well in reheating breaded and fried fish. Most toaster ovens will provide even, gentle heating. Always cover your fish with foil before placing it in a toaster oven and set it between 275 or 350 F and continuously check that it is heated.
• Oven: Preheat your oven to 275 or 350 F. Cover your fish in whichever dish or platter or pan you are using in the oven with loose foil if it is un-breaded fish. If your fish is breaded or battered, leaving it uncovered will help return crispiness to the outside, but you may lose moisture.
• Stovetop or Skillet: If a fishy smell doesn’t bother you, using the stovetop or skillet to reheat fried fish is doable. If you are reheating a fish stew or sautéed fish, using the same method they were cooked (stovetop) can be used. In a skillet, heat the skillet on low, add oil, and add fried fish.
• Air Fryer: This appliance circulates hot air around the fish so it cooks thoroughly and evenly while maintaining its crunchy exterior. Julie suggests following these five steps to achieve best results when reheating fried fish. Preheat the air fryer to 320 F. Place fish in single layer in the basket. Place basket in the air fryer and air fry for 3 to 4 minutes. Carefully flip fish over and cook 3 to 4 minutes more, or until the fish is thoroughly heated. Cool for 2 to 3 minutes and enjoy.
• Broiler: The broiler setting on your oven heats the fish at a high temperature, which allows you to reheat deep fried fish in a matter of minutes and still have crispy, delicious leftovers. Line the baking sheet from your toaster oven with aluminium foil. You can also drizzle a small amount of oil or spray cooking spray on the foil before putting your fish on it. Turn your oven to the broiler setting. Put the fried fish in the oven and broil for one to three minutes on each side. Make sure to watch the fish as it heats. You don’t want to burn the outside before the inside is thoroughly reheated. Your leftover fried fish will be ready to eat when it reaches an internal temperature of 145 F. Let the fried fish cool for a few minutes before eating it.