My kefir grains came from a lady who raised goats and cultured her grains using goats milk. The first time I made kefir from her starter, the kefir tasted of goat, I am not fond of that taste either: I used ordinary milk the first time, and there was a mild goat taste. The second time I made it, there was no goat taste.
While it is nice to have unpasturized milk, the kefir grows nicely in whatever milk you have available and the probiotics grow in it too.... so use your available milk as long as it is not the dead milk they call ultra pasturized (ultra dead milk) and you will be ok. Forget the wonderful unpasturized goat milk. It's goat. If you don't like it don't torture yourself, it doesn't seem to have made much difference to the final kefir product. Those of us who live in the states where we don't have the freedom to use unpasturized milk can make do.