I'm making a sparkling elderflower wine. It's in a 25l plastic bucket with a trap. The first fermentation went well. I racked it, added sulphites (Campden tabs), added fining, left for a couple of months. At this point the wine smelled great, but had a bitter aftertaste (not acidic), probably a bacterial effect, so I racked again and filtered, giving me a nice clear wine that tasted fine, with an alcolohol content of about 6.4%.
After reading various articles on sparkling wine making, I added more Campden tabs (a smaller amount) to ensure there were no more bacteria and left it for 2 days for it to gas out. Then I added yeast and a sugar solution for the secondary fermentation and bottled it. Now I'm finding that the fermentation is stuck - after a week, there is nothing happening in the bottles, no gas production at all. I've read that sulphites should be gone within a day or two, so it's OK to use them for sparkling wines if they are given time. I've also read that though sulphites are often used to 'kill' yeasts, they don't apparently kill them, just slow them down.
Is my second fermentation dead? Or do I just need to give it more time?
As the posted answers suggested it might, this did eventually kick off and it'a been a success overall. I'm still getting a slight bitter aftertaste, so this year I'll get the sulphites in earlier to make sure I kill off any bacteria before they get a chance to take hold.