A gray liquid collects on the top of the Culture during long-term storage under refrigeration. Known as hootch, this dark liquid is alcohol. If you feed your Culture daily, you likely won’t see this murky liquid.
Depending on your feeding schedule, you may sometimes find more or less hootch. If small amounts accumulate, just spoon them off and discard them.
An eighth-inch layer or more of hootch is a sign that your Culture has over-ripened. The Yeast are sluggish or even dormant, but they’re alive. The Culture must be revitalized before it can be used.