The Banana Thing Works!

I have a keychain LCD UV lamp, and I got it out yesterday and tried it on a ripe banana -- and it glowed blue! Now, the interesting thing is the blue was distinctly arranged around each brown spot and I couldn't observe it elsewhere, unlike the pictures in which the whole banana seems to be glowing. This makes me think that my LCD UV lamp, which only covers a portion of the spectrum a true UV lamp does, only selectively illuminates a certain kind of molecule. Perhaps it's a later breakdown product? Oh, the discoveries I could make if I only had the time -- and a few tons of bananas ...