Ripening

• Bananas are one of the few fruits that ripen best off the plant. If left on the plant, the fruit splits open and the pulp has a "cottony" texture and flavor. Even in tropical growing areas, bananas for domestic consumption are cut green and stored in moist shady places to ripen slowly.



• As bananas ripen, the starch in the fruit turns to sugar. Therefore, the riper the banana the sweeter it will taste.



• The commercial practice is to ripen bananas artificially by using ethylene gas, a substance produced by fruits that accelerates the normal process of fruit maturation.



• Temperature monitoring during ripening is critical. Normally temperatures between 58 degrees and 64 degrees Fahrenheit will be adequate. If ripening temperatures are too high (normally above 66 degrees) the fruit can become over-ripe too fast, soften but remain green, and or split through the skin.



• Relative Air Humidity during ripening is also critical and levels lower than 85% RH can produce ripe fruit with too much scarring and symptoms of dehydration, as well as fruit with a grayish tan.



• There are two types of commercial ripening rooms: (1) conventional rooms and (2) pressurized or forced-air rooms. The conventional rooms are cold rooms with adequate air circulation to move the ethylene somewhat passively around and through the fruit. Pressurized rooms create a pressure gradient between rows of stack boxes lined up into a tunnel with a differential pressure gradient between the inside and outside of this tunnel, and air is forced through the fruit, rather than around the boxes.



• Ripening programs usually run from 4 to 8 days. The temperature inside the ripening room is initially high and then is lowered according to when and what color stage the fruit needs to be taken out for shipment to the retail stores.



• Longer ripening schedules, with a more gradual reduction in temperatures are better for the fruit, but in many situations ripeners allow the fruit to go through as short a cycle as possible before releasing the product to the retail outlets.



• The color of the peel is used as an indicator of ripening progression. A scale of 1-7 is generally accepted: 1 is hard green, 2 is light green, 3 is more green than yellow, 4 is turning 50% green and 50% yellow, 5 is yellow with green tips, 6 is fully yellow, 7 is flecking and into brown.



• Most ripeners take fruit out of the ripening rooms and ship to retailers when at color stage 3.5.