How can you tell if a certain food is contaminated?

By the way it smells or tastes.
Hope this helps!

You can't tell from looking at, smelling or tasting whether the food is contaminated. Obviously, if the food does look, smell or taste off, then there's something there that shouldn't be. But if it looks, smells and tastes good.. it could still make you very sick. Buy your food from a good source you can trust. Store and handle it properly and be careful with your hygiene. Wash your hands often, particularly when handling protein foods.