How does an unripe fruit turn sweet a few days after it is plucked?

Question

How does an unripe fruit turn sweet a few days after it is plucked?

Answer 1

While not all fruits do this, the fruit ripening process occurs when enzymes inside the fruit turn starch into sugar. These same enzymes will also break down pectin, which is the substance responsible for keeping fruit hard. Therefore, as the pectin breaks down, the fruit will become softer and sweeter.