Basically any food can become contaminated if handled improperly. However, foods rich in protein, such as meat, poultry, fish, and seafood, are frequently the culprits in the food poisoning equation.
Two reasons for this is that protein-rich foods (meat) tend to be of animal origin. Therefore, microorganisms of animal origin are frequently found in animal foods. And animal foods are rich in protein that bacteria break down into amino acids, which are an important nutrient source to some bacteria.
In addition, bacteria needs moisture to survive and reproduce. Thus, they also thrive in foods with high moisture content. Some of these include starchy, egg-rich foods and cream-based foods, such as potato or pasta salads, cream-based soups, and custard or cream pies.