Thanks for bumping this...I wish I had a microscope so I could start at that wonderful plume on my Stonehaven. I seriously could read a paper on this subject and hopefully some nice microscopic photos would be included.
I seem to recall Greg Pease saying the silvery sugar-like stuff is crystalized oil from the leaf. I'll search around for the source (probably from the "Ask GL Pease" series here at pm.com)
Found it in Ask GLP Vol 44
No, it’s not sugar. There’s not where near the concentration of sugar for it to come out of solution. Even if you dry the stuff right down, the sugar is still bound into the leaf structure. The stuff that we’ve all seen is relatively insoluble in water, so I suspect it’s an organic salt that’s precipitating out as the pH of the tobacco changes due to fermentation. Yes, wild-ass-guess, but it beets sugar. (Beets. Sugar. Get it?)
I just opened a tin of Benjamin Hartwell signature blend from about '04 and it sure smelled boozey....I was wondering if something was going on like the OP wrote and maybe there was.....