I'm looking at what yeast need to live and nanners seem to have a fair bit of that. I have seen a lot of information on adding them for flavor. If nothing else I will be trying this soon and will update with results.
Banana does have a couple of the nutrients yeast needs. Potassium, folic acid, magnesium etc.
Most fruits lack FAN though.
That being said bananas wouldn't be a complete replacement for a yeast nutrient product.
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