Yes, barm is a Scrabble word!
...and is worth 8 points in Scrabble, and 10 points in Words with Friends
barm
Noun
1. A commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey
What Scrabble words can I make with the letters in barm?
3 Letter Words
2 Letter Words