One of the perennial questions we get is about mold on (self-fermented) vinegar.

Just two months ago, we got a meta question listing four questions on that topic, with the meta OP having the clear intention to post a fifth one. I wrote an answer with my definition of how we should decide on what is a duplicate. Now we got yet another question of this type, where the OP knows of the existence of the older questions and linked to them in the question body.

The OPs argue that their questions should not be considered duplicates, as this might be a different mold species than the one described in the older questions.

So, I hope that we clear this up as a community. Do we consider these questions duplicates of each other, or do we see them as separate questions?

Some points I would consider pertinent to the decision are:

  • Is it possible to make good distinction between different kinds of mold?
  • does our medium allow the OP to provide enough information for us to make this distinction? That is, are a picture and some verbal description of smell and maybe visual changes sufficient?
  • would the answers differ dependent on the kind of mold, or do experienced vinegar fermenters treat all the mold the same way?

Alternative suggestions to "always close" and "always leave open" are also welcome. For example, if we think that the questions could be covered well in a single well-written answer, but the existing answers are too unfortunately fragmented, we could write a new canonical question with an answer, and start closing as duplicates of that one. Or maybe you have some other idea how to best serve the people who have this problem?

1 Answer 1


It depends on whether any older questions have a sufficiently general answer that contains a method for troubleshooting mold in vinegar culture regardless of specific details. If one of them does, then yeah, others can be linked to that one as a duplicate.

However, I believe that folks should be able to post a new picture with questions around "hey, is this photo mold or yeast?" as an example. That would be unique to the photo involved, at least until someone else posts a similar photo (in which case it's a duplicate).

Basically, this all follows the general rule of "is there an answer on the older question that would answer this person's question?" which is the rule I believe that SA should be using 95% of the time.

  • 2
    I do not want to see us going the route of SFF, where they routinely close questions as duplicates where a single answer to the old question mentions, as an aside, something that could maybe answer the new question, if you tilt your head and squint just right. I think the criteria needs to be "would EVERY good answer to the old question also answer the new question?"
    – Marti
    Dec 5, 2023 at 23:01
  • 1
    So, there's two parts to the most recent question: (1) Picture, is this mold or not? (2) What should I do with the vinegar now? Part (2) is not at all new, and is a duplicate of multiple older questions. However, Part (1) is new, because the picture of their mold does not look like any picture posted on a prior question that I can find, and in fact is an identification problem, as noted in the comments; some people thought it was not mold.
    – FuzzyChef
    Dec 8, 2023 at 22:42
  • 1
    So what I'm saying is: if the new question did not have the identification portion, then I'd have regarded it as a duplicate. And if the photo in the new question had been similar in appearance to one of the prior vinegar questions, I'd also have regarded it as a duplicate. But because there is an identification component, and the photo is novel, it's not a dupicate.
    – FuzzyChef
    Dec 8, 2023 at 22:44
  • 1
    Making this kind of decision tree worse: many questions use temporary picture hosting.
    – FuzzyChef
    Dec 8, 2023 at 22:46

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .