ABSTRACT
C) decomposition of the food’s fat and protein components. Pyrolytic decomposition is the breakdown of substances at high temperatures and in the absence of oxygen. Various browning products, polycyclic aromatic hydrocarbons (PAHs), and heterocyclic amines (HCAs) are the major decomposition products of such cooking. On the other hand, baking, using an oven, or deep fat frying (unless the oil is repeatedly used or extremely high temperatures are used) does not produce such decomposition. PAHs are produced during cooking, mainly by pyrolysis of fats, whereas HCAs are pyrolysis products of amino acids, especially tryptophan. Also, PAHs can be from environmental sources, such as those occurring in wood-burning stoves, diesel exhaust, and oil-burning heaters. PAHs are formed when fat from food drips into the hot coals and is incinerated. The resulting PAHs in smoke can subsequently adsorb to the cooking food. Table 19.1 lists some common PAHs found in the environment.
