Anyone who throws the oil out after 3 - 4X of cooking is wasting perfectly good oil. I used to work in the food business as a food broker. The oil can be used probably 10 - 15X minimum before it needs to be tossed. You do have to strain it and add additional oil however. I keep the oil in the fryer and put a piece of Saran Wrap over the top and then closed / seal the lid. Works great! As others mentioned, potatoes help soak up the fish oil.
As a rule of thumb, change the oil when if / when: 1). it starts smoking or foaming, 2). when the breading doesn't brown to a golden brown (instead it's more black) or 3). when the food starts taking on a different flavor / smell (i.e. if you open the lid and it has a strong fish smell, probably time to go).
If you want a really good piece of fish, take a cast iron pan (marinate it in the oven first by rubbing the inside of the pan with Crisco and putting in a high heat (400+ degree oven)), and once marinated, add a bunch of Crisco to it till it melts down to liquid (you want apx. 3/4 of an inch of melted Crisco in the pan. Wash fish and pat dry (make sure you get the majority of the H2) off). Then take a small piece of breading and toss it in the pan to make sure the oil / Crisco is hot (if the breading starts to burn, turn down the heat.....if the breading isn't sizzling, turn up the heat). Once the heat is right, coat your fish in egg and dunk it in Shore Lunch (hands down the best breading I've found). Turn fish after a couple min. Don't overcook.
Pull from head and place on paper towel to soak up excess oil and serve. Not the healthiest
, but man it's unreal. Serve with tartar sauce (I mix my own using mayonnaise and dill pickle relish). Squirt some lemon on the top too.
This is also a great way to cook fish over an open flame when you're out in the bush and have a campfire (you'll need a metal grate to put over the fire).
