Summary
Removing profiles from a segment.
Details
If you wish to "erase" a profile assigned to a segment, you will have to distribute a profile with whatever changes are required. Either distribute the "default" profile (all categories set to "Recommended") or if you wish for a segment to not have any filtering, then you would distribute a profile with all categories set to "disabled". You can disable the category by "unchecking" the "Enabled" checkbox for each category.