If allowed to ripen on the plant, bananas will almost certainly be attacked by fruit bats. As bananas ripen, starch is converted to sugars, the fruit softens and the colour changes from yellow-green, to yellow, then gold, and eventually to almost brown, becoming mottled with dark spots. Under hot conditions, fruit ripens very quickly, but the skin colour turns a dirty green and the fruit becomes mushy. During summer months it is advisable to ripen bananas in the coolest room, near floor-level, or in an air conditioned area. Ripe fruit may be refrigerated.
Cold damage darkens the fruit's skin.
This may be reduced by wrapping fruit in several layers of newspaper and storing it high in the refrigerator, away from any cooling coils. If refrigerated, green bananas quickly lose their ability to ripen later at room temperature. They will, however, become mushy when completely thawed. Frozen bananas may be used in milk shakes, cakes, ice-cream and many other recipes. There are almost 300 known varieties of Musa , but in most Western countries it is rare for more than two varieties to ever reach the markets.