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:

• Do manacles provide any sort of in-game mechanical effect or condition?
• What are the specifics for a Block of Incense?

Notaly, loose salt does exist within the rules

It is listed as a trade good:

[...] 5 cp 1 lb. of salt [...]

It also appears during the Curse of Strahd adventure in Rictavio's Carnival Wagon as a jar of salt. Thus we know that loose salt certainly exists within the rules, but whether it comes with rations is not described in those same rules.

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, but 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:

• Do manacles provide any sort of in-game mechanical effect or condition?
• What are the specifics for a Block of Incense?

Notably, loose salt does exist within the rules

It is listed as a trade good:

[...] 5 cp 1 lb. of salt [...]

It also appears during the Curse of Strahd adventure in Rictavio's Carnival Wagon as a jar of salt. Thus we know that loose salt certainly exists within the rules, but whether it comes with rations is not described in those same rules.

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:

• Do manacles provide any sort of in-game mechanical effect or condition?
• What are the specifics for a Block of Incense?

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:

• Do manacles provide any sort of in-game mechanical effect or condition?
• What are the specifics for a Block of Incense?

Notaly, loose salt does exist within the rules

It is listed as a trade good:

[...] 5 cp 1 lb. of salt [...]

It also appears during the Curse of Strahd adventure in Rictavio's Carnival Wagon as a jar of salt. Thus we know that loose salt certainly exists within the rules, but whether it comes with rations is not described in those same rules.