Using the wrong bananas
Not all bananas are suitable for making banana bread. When selecting fruit for your bread, make sure to consider ripeness. Overripe bananas have the best texture and sweetness level for a satisfying loaf. Look for bananas that have begun to brown in the produce section. They may even be reduced in price. You can wait for more yellow bananas to turn black if you have the patience.
While blackened bananas are ideal for your loaf, avoid using fruit that has gone bad. Visible spots of mold and a foul odor are signs that your bananas are overripe for banana bread. In a pinch, the fruit can be "ripened" in the oven. Bake unpeeled bananas for 15 to 20 minutes at 250°F. Just keep in mind that this will not produce the same level of sweetness and may have an impact on the final product.