British ice cream maker Charlie Harry Francis and his company Lick Me I'm Delicious wanted to come up with something fun and unique to celebrate Halloween. So he did. He made glow-in-the-dark ice cream.
The Chinese had figured out a a way to synthesize the luminescent protein found in jellyfish. When combined with calcium-activated proteins, it glows. It must be agitated for the glow effect to kick in, which means that it doesn't glow until you lick it. So you can pretend you are some crazy radioactive alien who is just biding his time with a sweet snack until it is time to dominate humanity. Or something like that.
There are a couple of downsides to the glow-in-the-dark ice cream. First, it is jellyfish-flavored. I've had some weird ice cream flavors (including cheddar-jalapeno, and garlic) but I don't know about jellyfish-flavored ice cream. Second, the jellyfish proteins are expensive:Francis figured out that it costs over $200 per scoop. And third, well, who knows if it is actually safe? Francis had some and didn't suffer any (immediate) fall out or side effects, but I am old-fashioned. I was always taught my food shouldn't glow. Who is to say this won't turn into The Stuff?
Francis also created a sorbet that glows under UV light. That one is gin and tonic flavored, using quinine from tonic. The effect isn't as cool, but it is tastier and cheaper than the jellyfish version.