i have a yeast cake sitting on the bottom of a secondary since 1 month ago, its in a cool temp and is a 2007wyeast , this yeast cake also fermented a batch prior to this light lager, can i reuse after a secondary for a new batch?
Your best bet is to harvest yeast directly from the primary. Yeast are quite sensitive to alcohol and do not do well in the conditions found in a secondary. You can definitely try washing the yeast, but you're probably better off just getting a new batch of yeast for your next brew. You can wash from the primary without any problems with the new yeast.
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