In May, Samy Kamkar shared his latest creation on Twitter: chocolate that shimmers like a rainbow with a little help from science.

Rather than being a chocolatier, Samy is actually a founder of internet security company Openpath, and was infamous for releasing a virus on the Myspace social network back in 2005.

Inspired by a similar iridescent effect he’d seen on black plastic at a maker meet-up in Los Angeles and armed with a 3D printer, he wondered what else he could use the effect on.

He designed a 3D model for casting that included, at its base, a saw-tooth wave pattern. Each of the grooves is a few micrometres wide. The chocolate, when poured inside, adapted the inverse of this pattern on its surface.

Posting a video of the chocolate in motion to Twitter, Samy wrote: “I’m finally getting some decent results producing 100 per cent edible iridescent tempered chocolate.

I’m finally getting some decent results producing 100%-edible iridescent tempered chocolate. The colors are from the chocolate (not any ingredient or coating) diffracting light after being forcefully molded onto a diffraction grating in vacuum. pic.twitter.com/6wpbsIKh5C

— Samy Kamkar (@samykamkar) May 9, 2020

The colours are from the chocolate (not any ingredient or coating) diffracting light after being forcefully moulded onto a diffraction grating in vacuum.”

In December, researchers from ETH Zurich and FHNW University of Applied Sciences and Arts Northwestern Switzerland found a way to imprint a special structure on the surface of the chocolate to create a targeted iridescent colour effect.

The effect is achieved simply through a surface imprint that produces what the scientists refer to as a structural colour. The process is similar to a chameleon, whose skin surface modulates and disperses light to display specific colours.