Absorption through pickling in a sharp liquid
Question
Shalom, Rabbi,
I have two questions regarding the kashering of utensils through absorption by pickling in a forbidden liquid that is sharp (acidic):
1. When we are dealing with a utensil (for example, a tank or tanker truck) that contained a forbidden sharp liquid, and it is known that acidity can cause taste to be absorbed into the walls of the utensil through pickling in a relatively short time (there is discussion whether this is about 6 minutes or about 18 minutes), does the subsequent kashering have to be specifically by full hagalah (immersion in boiling water in a first vessel on the fire), or is irui from a first vessel sufficient, such as pouring boiling water from a kettle?
Can industrial washing with hot water of about 60 degrees be considered sufficient kashering, particularly when this is the standard and recommended method of cleaning such tanks?
I would be happy to see sources.
2. If we say that a sharp liquid can cause the absorption of forbidden taste into the walls of the utensil in a short time, why should we not say that a kosher sharp liquid can also cause the absorbed taste to be expelled and removed, on the basis of the principle “ke-bole’o kakh polto” (“as it absorbs, so it expels”)?
In other words: if the absorption took place through pickling in forbidden vinegar/acidic material, is there any reason to say that the kashering could be done by pickling in a kosher acidic substance that would cause expulsion?
Has anyone discussed this, or is there a source that addresses such a possibility?
Thank you very much.
Answer
Shalom u’vracha.
1. The rule that “pickled is like cooked” requires actual hagalah. In water at a temperature where it is bubbling (100 °C).
2. This does not help.
A source for this can be brought from the laws of yayin nesekh, where three times filling with water for 24 hours is effective, whereas for other matters we do not find such a thing. And why should it not be effective for everything with one time of soaking for 24 hours? It is evident that pickling does not expel to the same degree that it causes absorption.
And there is nothing surprising in this, for just as absorption in heat at the temperature of “yad soledet bo” (where the hand recoils) requires hagalah at a level of heat where the water is bubbling, so even though we say “ke-bole’o kakh polto” (“as it absorbs, so it expels”), this applies only to the type of process of absorption and expulsion, such as irui, cooking, and libun. But the absorption and expulsion do not operate with equal strength.
