Sodium Metabisulfite Question

This may be a silly question, but I'm a bit nervous. I am doing a coconut porter and plan to add toasted coconut to the mash, boil, and secondary. I am getting ready to toast the coconut and see my wife bought sweetened coconut with preservatives as opposed to the unsweetened, organic coconut I requested. I looked at the ingredients and see sodium metabisulfite as an ingredient and know this can kill yeast.

My question is - is there risk of killing my yeast if I add toasted coconut to the mash and boil? or is the amount used in the coconut minute enough and/or will be burnt off in the boil to be rendered harmless?

THanks so much for any advice. I don't want to ruin a hopefully declious (end expensive) brew!

You may want to repost this in the Brew Science forum. Or just buy the organic coconut and keep the sweetened for non-brewing purposes.

Adding sodium or potassium metabisulfite to your water pre mash is a recommended method for removing chlorine and/or chloramine. Once you heat it up, any leftover sulphur should dissipate quickly, and it won't cause issues any more. You should be safe using the coconut in the mash and boil, but you might want to avoid "dry coconuting" with it.

Thanks for the responses guys. I did some more research and eventually went ahead and added it to the mash and boil and lo and behold less than 24 hours in the fermentor there is significant airlock activity. I will indeed be picking up some organic coconut for the secondary.