Kashering Concepts


Hello Rabbi, I have a question. Scientifically, does the taste of items cooked in a metal pot (if not nowadays at least in the past) stay in the pot for 24 hours? As in will the next item that is cooked in it get some of the flavor? And does Hagolah work scientifically? And if so, is there a basis for waiting 24hrs as the Halacha requires? I understand libun works because it is literally burning the surface of the metal, so even if food is left it will burn. What about soaking in water for 24hrs? Thank you!



  1. Some kind of residue of the taste is absorbed into the metal pot. I am not familiar with the scientific data behind it but I would imagine that a large Kashrut agency like the OU would be able to answer the practical details. I once heard from my Rebbe (in a somewhat different context) that the scientific practicalities (or, in my case, the astronomical practicalities) do not dictate how we must act. Only the Halacha does.

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