Do rations contain loose salt?

One of my d&d groups came up against a giant slug (a homebrew monster) today, and one player decreed they were going to toss salt at it (this time, it wasn’t me who suggested it). The GM asked where they got it from, and the player responded that they probably had it in their rations, just loose for seasoning.

The GM was skeptical, and asked me to look it up (I’m a player, but I tend to be the one who looks stuff up). The PHB definition of rations is:

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

The player said that “including” means that that’s not the only stuff that’s in the rations, and that since salt is necessary for human health, it’s probably included in the rations. They also cited Roman armies sending soldiers with a salary, or salt money, just so they could buy salt.

The GM said that the salt would probably be in things such as hardtack or jerky, rather than just loose in the rations packet.

Is loose salt included in rations?