James of The Action Lab (previously) demonstrates how to imprint holographic rainbows onto tempered chocolate. This process, he explains, has everything to do with making diffracting patterns using quantum physics.
I talk about diffraction gratings and how they work. I show you how you can use them to make diffraction patterns on chocolate or other shiny materials.
Here’s the full video explaining the process in more detail.
James also shared a handy Instructables post that shared the full recipe written by Jellmeister.
To make the surface colourful with holographic rainbow shine, we are creating a microscopic structure in the surface of the chocolate itself, and it is this structure that makes light diffract into colourful rainbows, just like the rainbows you see on CDs or DVDs.