Formation of carcinogenic substances during heating of foods

The formation of some selected carcinogens during cooking is associated with some certain types of foods. The heterocyclic amines are mainly found in meat and fish that are cooked at temperatures above 150°. Acrylamide is formed in foods containing asparagine and reducing sugars which are present in potatoes, cereals and similar products. The formation of acrylamide needs high temperatures similar to the HCAs which are occurring during baking, frying, and roasting. In contrast to the other two types of substances 5-hydroxymethyl-2-furfural is formed at lower temperatures and even during storage from carbohydrates in presence of amino acids or from fructose by direct dehydration. Since all these compounds are by-products of the aroma forming reactions it is difficult to find ways to reduce the content in foods without changing the characteristics of the food products. A proper selection of the raw materials and well controlled cooking/processing procedures in combination with a reduced uptake of some highly contaminated foods can give us a possibility to reduce the exposure.