interesting thoughts - esp. in the context of (future) space travels …
My own pet theory is that pickling vegetables using lactofermentation might have been discovered completely accidentally by prehistoric coastal people - all you have to do is carry some vegetables* and sea water** home in the same vessel, then put them somewhere and forget to use them immediately, and you’re quite likely to end up with pickled vegetables after only a week or two. Sea water is pretty much the perfect salinity for fermented pickles and the pickling process is not much more than: put the vegetables in the salty water, then do nothing.
People that then did this on purpose would have a survival advantage over people who were only able to eat wild vegetables in season, both in terms of just having some preserved food, and because of the preserved vitamins.
*Coastal environments, at least in the northern hemisphere, are rich picking grounds for wild vegetables - indeed the wild ancestors of many cultivated vegetables (beets, spinach, carrots, cabbage etc) are coastal plants
**Carrying home sea water for use as seasoning for cooking makes sense if you don’t have dry salt, and most of your cookery methods comprise boiling things in a pot.
my gut feeling:
the whole lactoferment pickling is one of those things that were “discovered” prob. in 100s or 1000s of places at the same time → e.g. kimchi in asia
Also, Sauerkraut (and its assorted cuisine) is a rather alpine thing (not claiming that it is limited to the alps) … but def. the whole Sauerkraut high-culture is pretty much austro-hungarian/bavarian … so quite a ways off any sea…
but again, prob. discovered in lots of places w/out info interchange.
Well, I assume sliced, layered lemons, with salt in addition to the honey, and I wasn’t asked to make it cost effective. If the ratio of honey to lemon is high enough (with or without low temperature drying) it’s a minimal risk.
So how about crystallized (dried with sugar) citrus fruit?
A sugar coating might help to keep air away from the vitamin c. I think that’s sometimes how vitamin pills preserve it
Sauerkraut isn’t believed to have originated in the alps, but yeah, very likely invented/discovered many times.
Potatoes are quite high in vitamin c, and they can keep for months. You’d just need to know to keep them away from apples and onions (ethylene gas), and to check them from time to time since rot will spread.