various enzyme systems are readied for
action. When the seeds become capable of
growing on their own and the fruit is ready to
attract animals to disperse them, the fruit is
said to be mature.
The Work of Ethylene
and Enzymes
The final stage of fruit development is
ripening, a drastic change in the life of the
fruit that leads to its death. It consists of
several simultaneous events. Starch and acid
levels decrease, and sugars increase. The
texture softens; defensive compounds
disappear. A characteristic aroma develops.
Skin color changes, usually from green to a
shade of yellow or red. The fruit thus becomes
sweeter, softer, and tastier, and it advertises
these improvements visually. Because
ripening soon gives way to rot-ting, ripening
was long considered to be an early stage in the