I brewed a 100% wheat beer in early December and I pitched US-05 fermenting at 64 degrees. After primary fermentation completed I racked the beer into secondary and pitched about 10 lb of frozen mixed berries to make a fruit beer. The berries were left in a nylon sack which I removed from the beer after a week and I let the beer continue to ferment. When I checked on the beer again it had a thin, fuzzy layer on it. I tasted the beer and it doesn't taste sour, it's tart from the berries though. I found this layer of fuzz very strange and I attached pictures in hopes someone knows what it is. I was thinking it might be some proteins or pectin being pushed up to the surface, but I've never experienced this with other fruit beers and melomels I've made.
