Curiosity compelled me to crack a can of Saint Feuillien the other day.
Regardless of what I thought of the beer (a commercial non-lager Belgian beer in a can! Which didn't completely suck! but which wasn't what I was craving either), I'm intrigued by the ingredients listed on the can.
Water, malted barley, hops, yeast, sugar. Nothing unconventional so far.
Vitamin C though....
The only reason I can think of why one would add ascorbic acid to a beer is to prevent oxidation. Which leads me to wonder why the hell Saint Feuillien would think their beers are so susceptible to oxidation they need a pre-emptive shot of vitamins to cure their beer-scurvy.
A non-CO2-counterpressured cannery maybe?