|MadSci Network: Botany|
The book cited below gives a lot of details that I cannot provide here. Bananas are unusually responsive to ethylene and even half-grown bananas can be ripened with ethylene. Acetylene works but at least 100 times more acetylene is require compared to ethylene. Important factors in ethylene treatment are ethylene concentration (about 10 microliters/liter), controlling humidity to prevent drying out of the fruit (85 to 90% relative humidity), adequate ventilation to prevent buildup of carbon dioxide which slows ripening (keep below 1% carbon dioxide), optimal temperature (15 to 21 C) and both the stage of ripeness before treatment and the desired stage of ripeness after treatment which determines the time required. Because so much of world's bananas are ripened with ethylene, special ripening rooms are often built. Reference Willis, R.B.H. et al. 1989. Postharvest: An Introduction to the Physiology and Handling of Fruit and Vegetables. London: Oxford Professional Books.
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