A friend of mine who’s never made wine/homebrewed in any fashion before wants to make dandelion wine. He asked about the feasibility of “bottling” the stuff in mason jars. I’m a beermaker myself, not a winemaker, but is this a good idea? Since it’s not a carbonated product at least you wouldn’t have to worry about that, but I suspect evaporation, or perhaps even spoilage might be an issue with the jar lids.
Then I thought about suggesting processing the jars like you were making jelly, to seal the lid, but that can’t be good for the wine, can it?
The alcohol content of wine is high enough that spoilage shouldn’t be a problem. Your friend probably wants to use mason jars for the atmosphere. Take him to a brewing supply store and get him some proper bottling equipment. Real makers of dandelion wine bottled their wine. Jars are for moonshine.
He’s near an area known for moonshine, IIRC. 
I’ve pointed him at my favorite brewing supply house and suggested a hand corker plus corks, and saving wine bottles, but in case he’s set on this, I’m assuming an unsealed jar would let dandelion wine turn into dandelion wine vinegar? It’s been quite a while since I’ve done canning so I can’t recall if just wetting the inner seal on the lid will seal it, or if it needs to be heated up.
I’ve bottled mead in 1/2 gallon screw-top jugs with no problems.
Sterilize everything first, of course, but for the life of me I can’t think of a good reason not to. If the rubber in the Mason lid isn’t bothered by alcohol, a sealed container is a sealed container. Mason jars are good enough to protect food that’s prone to spoilage. The only thing I’d worry about it CO2 buildup if the little yeasties aren’t quite dead.
Don’t think he should “can” it, since I believe that involves heating the product in an unsealed jar which might lower the alcohol content. No idea what heating wine’ll do to the flavor.
I say go for it, and then let us know how it works.