I want to know how can we reduce the smell of fresh fish(may be caught 5-6 hour before). It smells really bad and after deep fry its remain in it. Some people use wheat flour mixed with white vinegar to wash it. But that does not works, we tried.
The smell is caused by a substance called trimethylamine. You can remove the trimethylamine by rinsing the fish under cold water, or use acids. A bit of vinegar or lemon juice throughout the cooking process makes for less fishy fish (this is why lemon pairs so well with seafood). Consider finishing with an acidic sauce (such as tartar sauce).