if you go to a home brew shop you can buy activated carbon , sometimes called activated charcoal
this is no doubt a food grade product as it is used to filter potable spirit , it usually comes in granular or pellet form
should be plenty of it as home distilling is legal in N.Z. ,,,don't think we could find any of the above in shops in OZ, [ sic ]as
home distilling is allegedly not permitted but we are allowed to own a still to purify water or distil flavours
using A.C. as an ash would raise the pH of your cheese slightly
* BILL ,,,,we had some rain last night and our chooks had a gorgeous meal of SCHNECKEN's
many regards,brian