[Based]

Is there a safe chemical or chemical reaction that will glow in the dark without the aid of a blacklight?

[kriggy]

Try Luminol
http://en.wikipedia.org/wiki/Luminol

[Ben Bob2]

Is it edible though? I wouldn't want to eat it...

"May cause gastrointestinal irritation with nausea, vomiting and diarrhea. The toxicological properties of this substance have not been fully investigated."

http://avogadro.chem.iastate.edu/MSDS/luminol.htm

[Arkcon]

Without the aid of a black-light, no, I don't think its likely.  You need a large molecule with multiple conjugated double bonds, and a strong red-ox, so that sounds dangerous to eat.  Also water quenches light generation (it "steals" the energy of the active state) and most things we eat are as water rich as we are.

If you're willing to have a black-light source around the food, I've just heard about "kryptonite candy" -- its homemade hard candy, dyed green, and heavily fortified with riboflavin. https://www.google.com/search?q=kryptonite+candy&ie=utf-8&oe=utf-8

[Corribus]

If you're willing to have a black light, plain old tonic water (which contains the potent fluorophore quinine) will do just fine.

[Arkcon]

But quinine, as the the internet says, is not nearly as tasty or as harmless in large amounts than riboflavin is.

[Based]

This isn't gonna be used in food but it will be exposed to nearly everything and could possibly be inhaled, eaten, etc.

Is there a way to use what they use to make glow sticks but in a small enough concentration that it is harmless?

[Arkcon]

No, but they make tiny glowsticks to make earrings, etc, and those could be left in or near foods if you want a glow.  Or even a tiny, battery operated, led lit, plastic cube that you can clean well on the outside.  The sushi place I go to often places such things under the bean threads when they want to make my dinner festive.

[kriggy]

Is it edible though? I wouldn't want to eat it...

"May cause gastrointestinal irritation with nausea, vomiting and diarrhea. The toxicological properties of this substance have not been fully investigated."

http://avogadro.chem.iastate.edu/MSDS/luminol.htm

oh I missed the "eddible" part..

[Arkcon]

I'd heard before, and finally remembered to look it up -- the Ancient Romans ate bio-luminescent molluscs.  http://en.wikipedia.org/wiki/Pholas_dactylus

[billnotgatez]

People used to ingest Mercury or bathe in radioactive pools.

I am not so sure I trust dietary habits of Ancient Romans.

 

[Arkcon]

I made a batch of kryptonite candy and brought it to work for Halloween.   People wondered if I'd used Green Fluorescent Protein instead.  *Shiver* is GFP edible?

[jasongnome]

Is there a safe chemical or chemical reaction that will glow in the dark without the aid of a blacklight?

https://www.youtube.com/watch?v=98p-9Ah2tF0

HTH!