Cheesemakers have long used ash coatings to protect and dry a cheese's exterior, to promote ripening and sometimes simply as a stylish accent. Ash is used most often with cheeses made of goat's milk (see chèvre). Though traditionally made from burned grapevines and roots, ash today is more commonly a powdered mix of charcoal and salt. Vegetable ash is made from dried vegetables reduced to ash.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.