As a home-based micro bakery, I have a family of sourdoughs in the fridge, a whole wheat starter (since 2001), a whole rye starter, and two white starters ( one made from kefir, the other from beer trüb). They were all “at death’s door” at one point, discolored, had a hooch and smelled very unpleasant. But they could always be revived. I, also, keep some old dough for half a year or more, untouched, in the refrigerator, before I use it for specialty breads.

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