I recently came accross this most interesting description on how you can brew your own banana beer in your back yard ahhaa.

This comes from the country : Burundi Kind of funny but sound like a good time ha.
BANANA BEER
There are 2 types of banana that go into making banana beer, the igikashi and igisahira. You mix the two types togther: 1/3 of harsh tasting to 2/3 of the other variety to ensure a balanced flavour.
You start by digging a hole, like a kind of home made distilery, big enough to pile up 5 or 6 bunches of bananas picked, the banana should still be green. Now Make a fire from dried banana leaves in the hole, and line it with fresh banana leaves to stop the bunches from touching the ground. Place the bunches in the hole and cover them with more leaves and rhizomes to hold the "still" up and keep it hidden for the kids etc haha.
In about 4 - 6 days later, check the colour of the bananaers which should be now be yellowish. Peel the bananas and place them inside big mixing bin. Then knead and churn them with bundles of certain certain grasses (called ishinge, or needles) in order to extract the juice. The first banana juice, called umutobé, can be served to women and children. You should be able to fill three to four 10 litre jugs of it.
To obtain fermentation, sprinkle each jug with ground grilled sorghum that acts as yeast. Then seal the jugs using banana leaves and leave them to stand near the hearth where a small fire is kept burning for a day and a half. Then decant the beer into medium sized jugs and leave it to stand for a whole day in a cool place.
Banana juice watered down with equal proportions of water is called urwawa beer. You can dilute the first juice as much as you like, according to your taste. Honey can also be added to pure fermented banana juice to make isongo mead.
country : Burundi
course : beverage
source : Cuisines d’Afrique / A. Villers (translation at
http://www.revuenoire.com/anglais/S23-4.html#Bière de bananes)
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