I keep waiting and waiting and waiting for a red tomato, and still waiting. It got me thinking, what happens that makes the tomato ripen? Just curious.
The actual process is triggered by the seeds within the fruit reaching maturity.
They then send a chemical signal to the plant to ripen the fruit so that it either falls to the ground and releases the seed or the fruit becomes edible for an animal to eat the fruit and carry the seeds off for distribution.
There are chemical methods of accelerating the process by the introduction of ethylene to the plant by sprays...or even keeping the fruit close to other plants that are producing the gas.
That's why toms in transport are kept seperate from flowers...and a banana skin placed in a bag with some toms will help the fruit to ripen.