Chemical reactions during cooking

The idea that reaction rates are tied to the rate of collision is aptly called the collision theory of reaction rates. But nature s mysteries are not so easily solved. During a chemical reaction, the electron orbitals (that is, the electron clouds) on individual reactants overlap and coalesce, the way two bubbles come together and merge into one. Once the conditions are right, it takes about a quadrillionth of a second for the electrons in the individual orbitals to readjust themselves into the orbitals around the products. But if all reactions took place as fast as collisions, then food would cook before... 

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... 

Let us carry this analogy one step further. Suppose we go on to cook our pizzas and accidentally burn one of them. Even though we theoretically have enough ingredients for three pizzas, we end up with only two. If this were a chemical reaction, the two pizzas would be our actual yield, the amount of product actually produced by a chemical reaction. (The actual yield is always equal to or less than the theoretical yield because a small amount of product is usually lost to other reactions or does not form during a reaction.) Finally, our percent yield, the percentage of the theoretical yield that was actually attained, is calculated as the ratio of the actual yield to the theoretical yield ... 

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