I had a similar experience recently when anything featuring lemon juice had a pronounced sulphuric smell and taste, like rotten eggs. All from freshly squeezed organic lemons from several different batches over a long time, all smelled great... until they were juice. Now I'm 95% sure it was long covid. Happily it was the only real symptom, and it cleared up eventually, but it was a rather odd few months. Seems to be a not uncommon reaction.