What Are the Brown Spots on Bananas?


One of the worlds favorite fruits, bananas are an excellent source of vitamins (C and B6) and minerals (potassium), and are low in sodium. The most familiar "dessert" banana, the green-to-yellow Cavendish, turns black when ripe.


The brown-spots on a banana indicate the starch-to-sugar process is nearly 100 percent complete, which is why ripe bananas taste so much sweeter than green bananas.


The chlorophyll in banana peels break down into particles called FCCs (fluorescent chlorophyll catabolites).

UV Light

A ripe banana, in visible light, is yellow with brown spots; however, when observed under ultraviolet light, the ordinary brown spots glow blue, according to the National Science Foundation.


A glowing halo occurs close to the dying tissue on the banana peel. Studies of the glowing blue halo, which occur close to dying tissue, provide a promising way to study apoptosis, or "programmed cell death," according to the National Science Foundation.

Fun Fact

According to the Oxford Dictionary, the banana plant, though called a banana-tree is not a tree but an herbaceous plant, or herb, meaning the plant stem does not contain true woody tissue.


  • Oxford Dictionary: Is a Banana a Fruit or a Herb
  • National Science Foundation: Bananas Glow Blue in UV Light
  • Google Books: How come bananas get brown spots
Keywords: banana, banana brown spots, ripe bananas

About this Author

Suzanne Fyhrie Parrott is lead graphic designer and owner of OneWay Advertising and Design. Established in 1988, OneWay provides professional advertising and graphic design services including marketing, SEO, Web content, targeted SEM, PPC marketing strategies, as well as tutorials and how-to guides for help in understanding how to implement basic marketing and design strategies.