The smell, taste and look of the food makes it unfit to eat. Food poisoning is caused by food that has been contaminated because it has been poorly handled, stored or not cooked properly. Food poisoning bacteria don’t affect the smell, taste or appearance of food.Look at the food below and click on the one you think has been affected by food poisoning bacteria.he smell, taste and look of the food makes it unfit to eat. Food poisoning is caused by food that has been contaminated because it has been poorly handled, stored or not cooked properly. Food poisoning bacteria don’t affect the smell, taste or appearance of food.