A peach of ripening advice
Peaches by La Grande Farmers' Market (cc by)
Former fruit agency and Whole Foods employee jocelmeow offers amazing detailed advice on how to find and treat yourself to the best peaches possible.
Ethylene (the fruit's natural ripening gas) output rises for a while but then levels off. The level of sugar the fruit contains and its red color stay exactly the same. The effect of all these changes is that the fruit goes from hard and sour to soft and sweet.