Proper storage temperature for green bananas is 56-58 degrees F, according
to the USDA. At that temperature, the fruit has an average storage life of
1-4 weeks. Compare this to grapes, with an average storage life of 50-100
days, or apples, with a storage life up to 6 months.

The transit time from the plantation in Central America, to the dock in New
York, in the 1940's and 1950's, could be between 1 and 2 weeks. Once at the
dock, the clock is ticking to get the fruit loaded onto a car and moved out,
to make sure the produce arrives in good condition.

As Andy points out, ripening bananas also produce ethylene gas, which
further speeds up the ripening process. Other than kiwifruit, a
non-steam-era product introduction, bananas are the only ethylene producer
which is also ethylene sensitive. Therefore, even though the ripening
process is slowed by cooling, it is not stopped, and the railroads needed to
get that commodity to it's intended destination. These were also years
before modified atmosphere packaging, refrigerated containers, and the
development of new varieties of fruits that can stand longer shipping times.

Michael Mang