And if you really want to get thoroughly grossed out, here's what my "A
Consumer's Dictionary of Food Additives" has to say about shellac:

  "A resinous excretion of certain insects feeding on appropriate
   host trees, usually in India. As processed for marketing, the
   lacca, which is formed by the insects, may be mixed with small
   amounts of arsenic trisulfide for color and with rosin. White
   shellac is free of arsenic.  Shellac is used as a candy glaze
   and polish up to 0.4 percent..."

I highly recommend this book. If you can't find it in your local
bookstore it should be available by special order through any
independent book store or major chain.
--
Linda Blanchard
http://www2.basinlink.com/us/mindpla/main.htm
celiacs and science fiction and NO MILK!