So I brewed a small American Wheat Ale on 10/19 (4.3 lbs Wheat and 4.5 lbs 2 row pale, willamette/citra, WLP001). After about 5 days, I racked it onto 10 pounds of Muscat grapes that I had cleaned and frozen, covered with water and brought just to boiling and cooled. The fermentation has been slow and steady ever since. I tasted some today and it's a little more tart than I wanted. I was concerned about this initially as the Muscats weren't all that brown banana color, although even the green ones were sweet and Muscat-ey. I am thinking that I want to rack this off of the grapes and stop fermentation to preserve a little residual sweetness to tame the tartness. As it is now, it has a very cider-ey quality.
There is a thick raft of grapes floating, and a thick layer at the bottom of the bucket as well. Should I just siphon between the 2 grape layers carefully? Or should I just wait for the raft to drop and see what happens with the flavor? Also, should I use campden or just cold crash it? I have campden but have never used it before.
edit: Or should I just cold crash it in the grape bucket?