You may all know this already , but if not ... when you buy a packaged food product , and see " natural flavor "  or " natural vanilla flavor "  listed , did you know that it might come from a beaver ?! Yup , tha's right , I said beaver , as in the little guys with the big teeth and flat tails that build dams . Castoreum is a food additive that is made from the secretion of the male beaver's castor gland , and is approved , and very widely used , as a food additive . Vegan , beware ! Or maybe , beav-ware !!!