Interesting Yerushalmi in respect of Kashrus

This is from Terumos. צתרי is sometimes translated as thyme (e.g. the Rambam. The ערוך also calls it some type of hyssop that provides taste)

Basically, Rav held that the thyme which wasn’t tithed was forbidden but Shmuel disagreed. That of itself isn’t surprising. What is surprising is that when Rav visited Shmuel, Shmuel fed him the thyme that had been infused with other food (and had a taste which one would probably describe as נותן טעם לשבח, even though he knew that Rav held it was forbidden. The מראה פנים on the spot gives an explanation where he claims that Rav had changed his mind. That is, somewhat strained? The Chasam Sofer tries to deal with this Yerushalmi as well in חידושי חת”ס על פסחים, עו, ב

דף נב,א פרק י הלכה ב גמרא פליגא מתני’ על רב אין צולין שני פסחים בתנור אחד מפני התערובות לא אמרו אלא מפני התערובות הא שלא מפני התערובות לא מי צתרי רב אמר אסור ושמואל אמר מותר אייכיל שמואל לרב מי צתרי

I haven’t spent much time on this, but I’d be interested to hear any nice explanations about this surprising story from learned readers.