### This is up to the GM

The whole and entire extent of what we know about rations is as follows:

> Rations consist of dry foods suitable for extended travel, including jerky, dried fruit, hardtack, and nuts.

Anything outside of this is the GM's decision.  
Whether "including" means "including but not limited to" or "including only" is effectively part of the world-building left to the GM. Perhaps they'll decide to leave this to the player characters and have them design/create their own rations, this would similarly be outside of the base rules and be something the GM would have to implement.

Notably, rations are not alone in being a barely-defined item:

* https://rpg.stackexchange.com/q/154396
* https://rpg.stackexchange.com/q/156245