How to make glowing food (that you can still eat)

This is an experiment which comes in very handy at Halloween. Having cakes that glow in the dark guarantees you to be at the center of the next Halloween (or birthday) party. Basically there are many ways how you could get things glowing in the dark. The only disadvantage is that most of these things (like zinc sulfide) are toxic and you don't want them in your food.

However there is one chemical that can be eaten and has the advantage that it glows when you illuminate it with UV light: quinine. Normally quinine is used to treat Malaria caused by plasmodium falciparum. However in a very small dose it is included in Tonic Water (although it is a myth that it was introduced in Tonic Water to cure the British troops from malaria, when they were in India - the dose would have been much to small even if they all drank nothing else).

Materials you need for this experiment:

Tonic Water	This makes your stuff glow under UV light
cake	There are much better sites on baking, so we won't explain how to make a cake but focus on the information you need to use Tonic Water in other recipes.

Information needed for getting started:

	In the glass on the left side is normal water, while in the glass on the right side is Tonic Water. If you illuminate it with UV light, the Tonic Water starts to glow.
	Even better you see this effect if it is dark.
	Tonic Water you can use in recipes (almost) everywhere where you can use normal water. On the left you can see a muffin where a modified version with tonic water was used for the frosting. Under normal light you can't see any difference to an ordinary muffin.
	However under UV light your muffin glows brightly!

This is something where you can really experiment a lot with to optimize the glowing effect. You can investigate which effect temperature has on the effect, whether there is an interaction with other nutrients (can they increase or decrease the glow?) and how you best combine the taste of Tonic with the rest of the recipe.

However there is one thing you should be aware of when experimenting with glowing substances: there are certain chemicals that absolutely kill the glowing effect (not just decrease it). One such a chemical that will kill your glow from Tonic water is chlorine. You might now think that is no problem since we don't do it in the swimming pool but the problem is that normal salt (=sodium chloride) consists of chloride. If you get salt near your glowing areas, they won't glow anymore.

This can be used to stop the glowing in certain areas (i.e. when you want to "draw" eyes and mouth or something else in your glowing canvas) but it would be annoying if already your first experiments show no glowing effect due to the salt problem.

Have fun experimenting!