Professing my love to chemistry.

While sitting in the "Intro to organic" unit in chemistry for about the third year in a row, I picked up an interesting little piece of information.

So apparently, apples dont really start fermenting in deficient oxygen. FOR glucose catabolism you need oxygen and when you dont have it in biology theyll teach you it always converts to alcohol instead of co2. Thats not always the case.

In the case of apples and a lot of other fruits, when they get large and the oxygen supply in the center of the apple gets depleted it starts converting to carboxyllic acid, which convieniently enough tastes bitter and animals wont eat it. Some would call this a mechanism of evolution because during this period the seeds arent ready to be spread.

When the center of the apple gets even more deficient in O2, it starts to make the alcohols. This is really neat. When an alcohol reacts with a carboxyllic acid they make an ester. Esters compose many of the worlds sweet smelling compounds. The carboxyllic acids are consumed in the reaction and the apple is no longer bitter but its now sweet or "ripe." The seeds are now ready.

This is the reason that small apples are usually very bitter and sour, because they havent been left on the tree long enough for the esterification reaction to take place.

oh chemistry. how do I love thee? let me count the ways.....