Be aware that it kills your good bacteria, we think - Jhan did a yogurt test on several substances, and xylitol killed the good bacteria, resulting in no yogurt from that batch of milk. the post is a few pages back somewhere, you can do a search for all of Jhan's posts to find it if you want.
I did a test on other things, to see that post, go to the "BSA" posts (link at top of page)