A fantastic book and available on the Web (free) about Fruits is: Fruits of warm climates. Julia F. Morton in:
Excerpt interesting about Bananas (a chapter fantastic!)
In Polynesia, there is a traditional method of preserving large quantities of bananas for years as emergency fare in case of famine. A pit is dug in the ground and lined with banana and Heliconza leaves. The peeled bananas are wrapped in Heliconza leaves, arranged in layer after layer, then banana leaves are placed on top and soil and rocks heaped over all. The pits remain unopened until the fermented food, called "masi", is needed.