Cooking, meat, chemical reactions that

The millions of chemical substances—natural or artificial—that have ever been cataloged have had profound effects on the human race. Cave men and women did not know it, but their discovery of how to cook foods, especially meat, altered forever the development of modern humans. Cooking is a chemical reaction that makes food easier to chew and swallow, more digestible, and freer of harmful pathogens, all of which contributed to improved human health, increased life spans, and accelerated brain development. 

All ingredients in meat (proteins, lipids, carbohydrates) react during the normal meat preparation in a very complex chemical reaction to produce the final, highly appreciated flavour. It goes without saying, that each cook finds a new balance of this... 

It appears, then, that there is a general, meaty aroma, common to cooked beef, pork, and lamb (and probably poultry), attributable to the pyrolysis of the mixture of low molecular weight nitrogenous and carbonyl compounds extracted from the lean meat by cold water. But the aromas of roast beef, roast pork, roast lamb, and roast chicken are unmistakably different. The chemical composition of the muscular fat deposits of these animals differ appreciably, and it is to these lipid components that we must look to account for the specific flavor differences. Heating the carefully separated fat alone does not give a meaty aroma at all, much less an animal-specific one. It is the subsequent reactions of pyrolysis products of nonlipid components that give the characteristic aromas and flavors of roasted meats (20). 

Compared with other subjects, chemistry is commonly believed to be more difficult, at least at the introductory level. There is some justification for this perception for one thing, chemistry has a very specialized vocabulary. However, even if this is your first course in chemistry, you already have more familiarity with the subject than you may realize. In everyday conversations we hear words that have a chemical connection, although they may not be used in the scientifically correct sense. Examples are electronic, quantum leap, equilibrium, catalyst, chain reaction, and critical mass. Moreover, if you cook, then you are a practicing chemist From experience gained in the kitchen, you know that oil and water do not mix and that boiling water left on the stove will evaporate. You apply chemical and physical principles when you use baking soda to leaven bread, choose a pressure cooker to shorten the time it takes to prepare soup, add meat tenderizer to a pot roast, squeeze lemon juice over sliced... 

Amino-imidazoazaarenes types of HCAs inclnding IQ, IQx, pyridines, and furopyr-idines are generated at normal cooking temperatures (IOO-300 C). AIAs have been found to be responsible for most of the mutagenic activity in cooked foods, especially in Western diets [34]. Therefore, identification of precursors and elucidation of their mechanism of formation is needed for later development of strategies to inhibit their formation. For this purpose, model systans that simulate the chemical environment in the meat were developed, in which complex side reactions are reduced and reactions of other constituents of the meat that are not involved in the formation of HCAs are excluded [35]. 

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