Campden tablets = bad smell!

[mfischer2]

I had to add some cane syrup back into a beer I made with a friend (it's a gluten-free beer). We kegged it and then added 5 campden tablets, 1 per gallon, in order to keep it from fermenting further since we were going to bottle it for him to drink. The beer was fine when it went in, but now it has a distinct sulfur odor to it that makes it smell real bad. The campden tablets are sodium metabisulfate, so there's obviously sulfur there, is this the cause? Can I vent this odor off somehow? Did I use the campden tablets incorrectly?

[Madtown Brew]

I've only used campden tablets once, to knock down a unpasteurized cider before adding fresh yeast. However, I only used 1 tablet for the whole 5 gal batch. 1 tablet per gallon seems like a lot.

[rhino777]

1 tablet per gallon is what I've seen in many recipes and what I used in my hard cider I made last fall and it turned out really nice. Still have a couple sixers left I'm trying to string out until this fall's apple harvest.