Make Edible Ice Spheres With Cryogenic Liquid
This is a pretty neat trick. I thought before, you have to use liquid nitrogen to make effectively hollow ice sphere. But here they just use dry ice and isopropanol.
The actual problem of liquid nitrogen is the storage. You need to have ridiculous expensive containers to have it... While dry ice [frozen CO2] doesn't last very long, you don't need necessary a special container for it. And the isopropanol could be used over and over again.
Thanks for this amazing idea...