Are questions about preservatives off-topic?

Question

There was a recent answer which says

If that were the case, adding some preservative on your own could help; but preservative dosing takes you out of the realm of Official FDA Recommendations and is thus out-of-scope for this site.

Is this actually the case? If so, why? There is no close option to say it's off-topic on the basis of not being within the realm of FDA recommendations.

Answer 1

Argument: they should be on-topic. They're about cooking for humans, and there is referencable, online, authoritative material recommending preservatives which can be quoted in answers.

See my answer to the vinagrette question for an example.

Answer 2

Suggestion R2 We can write up a canonical question and start closing all these additional questions as duplicates. A canonical answer to that question could then explain the erroneous thinking behind the question, and try to systematically give some knowledge on the basics of food preservation.

Advantages:

• when answering each question separately, bad answers snuck in easily and confuse people, or require active interaction and have the potential to cause drama.
• when answering each question separately, people sometimes write a great answer under one of them, that is applicable to any of these homemade recipes - but it stays there, and is not seen by the people who write or read the other threads.
• sometimes these questions attract only 1-2 answers, which don't cover the full gamut of options. Pooling the answers in one canonical question helps the askers by enabling access to more information
• We can invest the time to write a thorough, educating, well-structured answer for a canonical question.
• It leaves us the flexibility to leave questions open in the edge cases where there is a better answer. For example, there is a formula for how much salt to add when making sauerkraut, in order to create a safely preserved product.

Answer 3

Suggestion R1: We can leave the questions open, and let each of them get answered separately. The answers will pretty much always cover the same ground - give the project up, or use a freezer, or pay a commercial lab to do the testing for your specific recipe, or make something else out of it (e.g. add enough acid and salt so the salad turns into a pickle), etc.

This is how we have been doing it until now. The advantages: It is the path of least resistance, and requires no additional rule-creation, and it needs no work to set up. Disadvantages: the usual ones of leaving practically-duplicates staying around open (see the list of advantages on R2 for an incomplete list).

Answer 4

Suggestion R3 We can postulate that, since there is no way that a straight answer to the question will satisfy food safety guidelines (to my knowledge, the FDA has never approved a preservative-based method for home use), the question is inherently opinion-based, since it uses a definition of "safe" that is based on a personal judgement. In that case, these questions would have to be closed, not because they are out of scope, but because they are opinion-based.

I am adding this option because I believe it was the line of thinking in the post that prompted the question. Advantage: It makes it clear to users that we do not want answers based on personal conviction, like "Just throw in 0.5% of magiconium wondrate and you're good". The disadvantages are: a lot of frustration to the askers, and missing the opportunity to explain to them why their mental model of food preservation is wrong.