It's probably dark due to the juices used on it. Could also be how wet it is. I have found that anything other than perfectly clear juices tend to darken in color even more on Ekowool after being burned for a while. Ekowool sleeves are great for ss mesh/rope, but can be hard to do if you don't have a good deal of wick already above the deck...or smaller hands. Torching it before sleeving can help it from fraying. If you can figure out a way of sleeving it without it fraying, you don't need to torch it.