What I Heard About Herring Turning Red, Plus More Delightful Herring Info From 1800

I was watching one of my favorite YouTube people when he went off on a tangent and mentioned the reason herring sometimes turned into "red herring" is the use of a impure salt which contained enough saltpeter to cause the red color when the brining is heavy.  The same salt for less time doesn't cause a color change I think.  The nitrates in the salt do the reddening, like ham and so forth is so pinky for the same reason.

I am still looking for confirmation of this info, but this was fun to read.

From:  Philosophical Magazine, Comprehending the Various Branches of Science, the Liberal and Fine Arts, Agriculture, Manifactures, and Commerce

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