|MadSci Network: Chemistry|
If the stearic acid (one of the fatty acids in meat) is subjected to high heat, it will char, probably simultaneously reacting with the protein present to form heterocyclic amines, which are known carcinogens. This is the 'burnt', charcoal-like substance on the outside of the meat. Stearic acid is a hydrocarbon, so the oxidation products generated by itself with heat and oxygen are carbon, carbon monoxide, carbon dioxide, water and intermediate hydrocarbons. If the stearic acid is not heated high enough to char, it will just melt, making the fat liquid and juicy. It will congeal (if beef or mutton) on cooling.
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