Fluorescing Gin & Tonic




About: Analog maker dabbling in digital manufacture

Tonic water contains quinine, a fluorescent alkaloid. Put some in the path of a UV light, and you'll see a beautiful bright blue beam. You can create fantastic effects in a gin & tonic with a UV keychain flashlight - serve some up at your next party, or just take along the flashlight next time you go out, and order a G&T (you'll soon find out if you've been served a gin & soda instead - it won't work!).

Note: you'll see this effect any time you have a tonic-containing drink under a blacklight. See How to Make Edible Glowing UV Reactive JELLO, for example.

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Step 1: Ingredients

You'll need: Gin ~ tonic water ~ lime ~ ice ~ UV LED keychain flashlights

I bought the flashlights from DX as "UV Money Detector LED Flashlight Keychain 10-Pack" for $5.24. Allow a couple of weeks for them to show up. You can buy them at the dollar store, too.

Step 2: Build & Serve

Add ice to a clear, pattern-free glass. Add gin & tonic in about a 1:6 ratio (they're usually stronger, but here you want good volume and plenty of quinine for best effect). Garnish with a slice of lime. Make one for each guest. Note: a virgin (no gin) version might need some Sprite or similar to sweeten it up a bit for that crowd. 

Give one to each guest along with the UV LED. Once everyone's set up, switch off the lights. They'll figure out what to do next :)

Enjoy! Video shows what you can expect. You'll get 99% of the effects in the first 30 seconds, so no need to watch the whole thing.

I skipped the lime and ice for this demo. The ice causes condensation on the glass makes the picture a little fuzzy, at least on screen. However, don't skip it when you try it - you get additional effects shining the light down through the ice.

If you liked this drink, you might enjoy The Color-Changing Martini.
Other drinks involving tonic water and blacklights can be found in the ebook Shocktails.

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    18 Discussions


    7 months ago

    Boil it down if you want a very bitter but highly concentrated version of this.


    3 years ago

    That's amazing! Looks like Nuka Cola Quantum from Fallout!!

    1 reply

    Reply 3 years ago

    I will take your word for it :)


    7 years ago on Introduction

    wow this is non alchoholic right also for the light you could use led taplights mod the lights to use uv leds from ebay

    1 reply

    8 years ago on Introduction

    I cant wait to try it! But do you really need all the other stuff if the glowy part is in the tonic water? Also will the LED keychain flashlights they have on http://LEDKeychainFlashlights.com work for this? Or do I have to go to amazon or something? Thanks!

    1 reply

    Reply 8 years ago on Introduction

    You only need the tonic water and a UV keychain flashlight. You can buy them at the dollar store. Have fun!


    9 years ago on Introduction

    Cool! Now to build glasses that have a light shining up through the bottom that goes on when you set them down. . .

    5 replies

    Reply 9 years ago on Introduction

    Use LED lighted plastic Ice Cubs in the drinks as described below. Ironically, I have a pair of bottom lighted glasses as you suggest. They were made by Geni Ware Company many moons ago. Don't know if they are still in business...this was 30 years ago. :-) Uses small battery and twist on switch at bottom to turn on the light.