I worked as a generalist on this one at Tendril Studio. I've made the sculpting model (Zbrush), particle generation (To use on Zbrush), shadinr/render and Pre-Comp in Nuke.
I tried a different approach on start, doing the base texture on Substance Designer + Painter. The "problem" is. That thing in real world is tiny, and it was NEVER used BIG before, so, we took a bunch of macro photos to look how was the "texture" of its surface before starting, and we saw a LOT of layers and details that are impossible to see on a naked eye. BUT the CHEX need to appear BIG on screen for this piece and it needs to have a match with the real product at the start of animation.
So in the end it needs to look like something between the macro shots and the real tiny Cereals, but it needs to be big on screen. :) I made a lot of scatter distributions and some displacement layers and mixed everything up using zbrush + sculpted over it a bit.