Currently they seem to be hardcoded and then given a JEI integration page, it'd be nice if this could be a JSON recipe so you could datapack them + easier for addons

Second this. Been trying for an hour to figure out how to do this. I understand that the aging itself is hard coded but being able to show the aging of the cheeses I've added with my support mod would be amazing

I understand it not being recipe compatible from a game play side, I've already added the aging effects to my cheeses in Chewy Cheeses. This is more about adding the visual JEI guide part

The main issue with aging is that it's not exactly a crafting recipe compatible thing. It's an in-world random chance based trigger, which wouldn't really work well with the recipe system. I'll see about adding customisability in a different way in the future.

We also plan on reworking cheese aging a bit in the future too, so that's something else that'll need to be considered with anything we do.

Any way you recommend adding to the list here from our end?

Mhm, I'll see about making a more public system for aging JEI recipes.

That was something I didn't touch, and I agree, it's kinda meh for addons.

Thank you that would be amazing!