Kashering Vessels: Kashrut - Vessels Response on Ask the Rabbi
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Kashering Vessels

Is there any other way to kasher silver cutlery except by boiling it? Perhaps one can use some disinfectant?

The Aish Rabbi Replies:

The reason we boil non-kosher cutlery is because (for example) when a knife is used to cut hot pork, some pork flavor became absorbed into the knife. The only way to remove those "taste particles" is to boil it out. Spraying a disinfectant only addresses the surface issue, which can be rectified with soap and water. But the spray will not extract the particles that are embedded inside the knife.

Here's the boiling procedure you should do, called "hagalah":

For metal utensils: Let them sit unused for 24 hours, and make sure the item is completely clean. (If there are crevices, you will have to clean out any gook.) Then you need to find a really big pot. Fill it with water and bring it to a bubbly boil. Then insert the utensils you want to kasher. They must be fully covered by the water. Also, since the utensil will cool off the water somewhat, you have to leave it in long enough so that the water reaches a boil again. The optimum time is to leave the utensil in for 30 seconds, and then remove it. (If you leave it any longer, there's a problem of re-absorption.)

If you want to kasher a pot that is too big to fit into another pot, then there is another option: Fill the pot to the very top with water and bring it to a bubbly boil. Then put something (like a stone) into the pot, so that the boiling water flows over the sides. Not complicated, just messier than the first method.

"Hagalah" works for pots and cutlery – i.e. things that came into contact with non-kosher food through the medium of hot liquid. But frying pans used on the fire (without liquid) is more severe – because the pan absorbed the non-kosher substance more directly and intensely. So if you want to use kasher a pan, then you have to burn the bad stuff out! This is called "libun," literally getting the metal red-hot. You basically have two choices: use a blowtorch, or put the pan in with the cleaning cycle of a self-cleaning oven. (Just be careful that the plastic handle doesn't disintegrate.)

Perhaps the most practical option is to call your local synagogue and find out when they have their pre-Passover "kashering day." This is where they prepare a huge public vat of boiling water and bring out the blowtorches. Here in Jerusalem, you can even find kashering stations set up on the street corners!

One final note: Generally speaking, people today try to have a separate set of pots and silverware for Pesach. If you can afford it, it certainly simplifies things.

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