Over the summer I made a small (400ml) starter of yeast from the bottom of two bottles of Bells Oberon. The yeast took off after about 4 days and was finished fermenting after another 3. I've kept the yeast at about 60 degrees since.
I'd like to use this yeast to brew a batch... but how to I know if it is still good?
Primary: North of the Border Vienna
Secondary: West Coast Blaster
Kegs: Common Room ESB, Belgian Wit
Bottles: Steinbart's Oatmeal Stout