I've got one of these glass bottles with a round cork, and while they're not completely air-tight, they do an excellent job. I know this because I have some very pungent items in it and the room does not perfume with their odour, as if left uncovered. However, If I put my nose right at the opening then I can smell it, but otherwise cannot around the room (and it's a well insulated small room so odours usually linger).
I would like to know if there is a use case with any foodstuff where the slightest amount of oxygen would be beneficial for it? I can think of Apple Cider Vinegar, with mother, of which requires oxygen to grow (as well as sunlight), and the cork would help keep the flies out, but can anybody think of any other foodstuff use case ?