>>35484650I imagine them to be part of the Palkie digestive system that can store food for a prolonged period in an environment conducive to fermentation. Ruminants like cow and sheep have them as their first stomach while some other herbivores (including opossum) did that in their intestines. It’s inspired by how opossum can vomit partially-fermented food as a self-defense mechanism but I decided to take some liberties for more versatility. It probably originated as the same thing for Palkies but had since evolved to be more effective (by having them as separate sacs closer to the mouth instead of the tail end of the GI tract) and versatile (they have some control of what goes in them to control the material of fermentation) in the form of generating and storing lifting gas
For Palkyries the mechanism’s probably the same but their bigger body and brain (maybe) let them use the fermentation sacs in more creative ways like making/storing poison as spit weapon like in my first story! As for wine fermentation I think the body’s too warm for that but maybe some specific alcohol could be made there if the material’s carefully selected. Odds are you’ll have better luck with cheese or other fermented local delicacies though