My LHBS carries organic cacao nibs from brewers best and ive seen two batches becoming infected both that were aging on these which makes me think they need to be sanitized to kill anything funky on them before use. Whats the best way to do this?
Also I was talking to someone who wanted to put some homemade soft caramel into his beer. I advised the best way might be to separate some of the wort into a double boiler and melt the caramel into that before adding to the beer, or even adding back to the beer at flame out. Would you retain any of the caramel flavor? Certainly it would add gravity to the beer because of the sugar. Do you think there would be any negative contribution to the beer/equipment, maybe head retention to the beer? or sticking to your equipment?
As far as the nibs go, I'd soak them in some high-proof neutral spirit (vodka or 151 Rum), then add the whole thing into the fermenter.
For the caramel - this is just sugar/water caramel, right? If there's butter or some fat in them then I'd be worried about head retention, otherwise it should be fine. I think your double-boiler idea would be fine. Unlike other sugars, I'd guess that you'd be able to keep some caramel flavor in the finished beer, since we typically caramelize the runnings on Scottish ales and that works just fine.