Very ripe banana 
Very ripe banana, with the skin already speckled black.
Characteristics
- As it ripens, the starch in the flesh turns into sugars (sucrose, glucose, fructose).
- It is rich in potassium.
- It appears in traditional Indian preparations and fruit ferments.
Role in the preparation: It is mashed or blended to give the preparation easily fermentable sugars.
Caution: It attracts flies: work in a container covered with cloth and do not leave scraps in the open.
Sources: Banana - Wikipedia
Documentary information: this is neither a recommendation for use nor a plant-protection or veterinary claim. Check your country's regulations before any use.