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Koshering Utensils for Passover

Koshering Utensils for Passover


Koshering is the process by which one makes non-kosher vessels and utensils kosher. Regarding Passover, koshering refers to the process of making chametz vessels and utensils kosher for Passover.

Year-round cooking utensils and vessels cannot be used on Passover unless they have been properly koshered, since they have absorbed chametz by contact or use. The same general procedures by which we kosher vessels that have been used for non-kosher food apply to koshering chametz vessels for use on Passover.

The following is a general description of the koshering process. The details are intricate, however, so it's best to consult with your Rabbi before you begin.

Methods of Koshering Utensils

It is important to note that there are certain kinds of utensils that cannot be koshered at all. This includes materials such as china, pottery, or enamel cookware. In addition, items that cannot be fully cleaned, such as sieves, graters, food grinders, pocketknives, etc., also cannot be koshered; neither can items that are likely to be damaged by the heat of the koshering process, such as knives with glued-on handles.

The method of koshering is based on the principle that the way the utensil absorbed the chametz is the way the utensil expels the chametz, and thus is the manner in which it is koshered. For example, a pot in which chametz (e.g., soup, pasta, etc.) had been boiled, or a spoon used to stir that pot, is koshered by immersing the pot or spoon in boiling water, thus removing the chametz with the same force by which it was absorbed.

However, if the chametz was absorbed in the utensil directly through the fire (without the medium of water) — e.g., a baking pan or grill — it is removed through applying direct fire to the utensil, as with a blowtorch or the like. The fire must be applied until the utensil is red hot.

To kosher a standard oven for Passover, it must not be used for 24 hours, and then it must be cleaned thoroughly and heated to the highest temperature for several hours. The racks, and the lips or grooves on which they rest, must be heated until glowing red. Some people use a special metal insert in the oven after koshering it, as an extra precaution. The method of koshering varies from oven to oven; consult a Rabbi for the particulars of your oven.

Procedure for Koshering by Immersion in Boiling Water

Utensils must be thoroughly cleaned and then not used for twenty-four hours before koshering.

One can use a chametz pot for koshering utensils, as long as it is not enamel-coated or earthenware. It must be perfectly clean, and must not have come in contact with chametz in the past 24-hour period. The pot should be filled with water, the water brought to a boil, and a hot stone or hot piece of metal dropped in, causing the water to overflow. The water should then be poured out and the pot rinsed in cold water.

The pot should be filled again and the water brought to a boil. Utensils can now be immersed in the boiling water. Items should only be put into the pot when the water is boiling, and taken out with special gloves or metal strainer when it is boiling. If the water ceases to boil, wait until it begins again. The pot should be big enough to allow all surfaces of the utensil to be touched by the water; each object should be dropped into the pot in such a way that it will not touch the sides of the pot. If there are grooves in the knives or pots, the chametz must first be burned out by heating it over a flame until the heat penetrates to the other side, and a piece of paper placed on that side will burn on contact. The utensil can then be koshered by immersion in boiling water. After immersion, it should be rinsed in cold water.

When koshering utensils in a pot, do not put in too many utensils, to ensure that there is enough room for the bubbling water to cover each utensil.

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Yisroe Cotlar Cary, NC via May 7, 2014

Re: You raise an important point. That together with the physical cleaning is its spiritual significance of removing one's ego and pride, the "internal chametz,"

But here's the thing:

Judaism is action-oriented. It begins with the act. The deed in accordance with every part of the laws passed down in our tradition. And Torah tells us that it is this deed that creates the connection with G-d. G-d desires the deed.

That being so, the deed is also to be instilled with KAVANA - meaning, depth, spirituality. This is like the soul of the Mitzah that allow the deed to be that much richer and more beautiful.

But one cant only focus on the KAVANA and miss out on the deed itself. It's easy to do as the spiritual meaning often seems more meaningful and holy - however, in truth Judaism is not about "what feels spiritual", but rather, what is asked from us by G-d.

And so, we do both. Clean our homes in accordance with every detail of Jewish Law and also study and internalize its deeper meaning Reply

Daniel Vancouver via April 14, 2014

Halacha and Aggadah Without Aggadah, Halacha is meaningless. Taking de-chametzing too far affirms an alien concept of original sin. Our own bodies would then be hopelessly contaminated by chametz and have to be disemboweled to be purified.

Fetishizing chametz-removal to the nth degree makes it impossible to achieve and is a form of idolatry. Remember the reason for chametz removal and its symbolic meaning. In removing chametz we are preparing mentally to relive the ancient exodus and providing children a means to understand basic ideas. Symbolically we are cleansing ourselves of the slave mentality and the objects and attitudes by which we are enslaved. External purification is symbolic of inner purification, not vice versa. Inner purification depends on God, not on cleaning.

Chametz is in the air, as pollen, dust and sublimated molecules. Boiling chametz causes airborne contamination. Ritual is easier than inspiration and can serve as an excuse for spiritual effort. Experience the light. Reply

Yisroel Cotlar Cary April 2, 2014

Re: This is Judaism! Where we connect to G-d based on what is written in Torah and asked of us even it might seem something else "feels more spiritual." For example, eating physical Matzah on the night of the seder is actually more important than meditating on the freedom (though of course that should be done as well)

There is incredible importance to physical action even when it does not "seem spiritual or meaningful." For this is what is asked of us.

Now that being said, we are not angels. We do the best we can cleaning our house for Chametz and then:

1) nullify Chametz we did not find.
2) sell Chametz we know about, lock away, and want to save until after Pesach.
3) Offer a prayer while we burn our chametz asking G-d to remove our personal "evil inclination" just as we removed all the chametz in our house..

But we should know there is deep significance to our physical cleaning even if we don't always sense it. Reply

Avi North Miami Beach, FL March 31, 2014

Cleaning Ray,

I think I understand what you are trying to say, and it is obviously good to focus on the goodness of G-d and what He has done for the Jewish People. However, we do that everyday during prayer and each time we do a mitzvah for the sake of Heaven. Are you saying that the mitzvah of removing chametz is somehow lesser and unnecessary, G-d forbid? What is your point? If we don't remove the physical chametz before Pesach, we cannot possibly observe the holiday and observances thereof with all the spiritual aspects included. If you are unsure of what is involved, please ask your local Orthodox Rabbi for help. Now is the time, as you still have plenty of time to make your home Kosher for Pesach, and therefore your soul, mind, and body kosher all year long. A Kosher and Joyous Pesach! Reply

RAY March 28, 2014

Chametz Cleaning I find it to be impossible to clean all chametz from the house. I feel a good cleaning is good but in spending so much time and energy cleaning we have left G--D out of the equation. It is like cleaning the outside of the cup and the inside is still dirty. We should spend that time and energy focusing our attention on cleaning the soul. In this day and age when the world is so evil we should focus our attention on what G--D did for the Jews. It was the greatness of His love that brought us this far. What would happen if the time was spent praying for the world in such a drastic state. G--d looked and saw the plight of the Jewish people and heard their prayers. Let us stop taking so much time cleaning and more time focus on the goodness of G--D. PLEASE PEOPLE! Reply

Anonymous Long Island, NY March 13, 2013

When I was a kid my parents had sets of utensils and dishes which were put away for use on Passover only. They lasted 50 years. No fuss or buying new ones each year. Reply

Aviyah Chattanooga, TN April 18, 2011

Dishwashers Unless the dishwasher has never been used for chametz, you should forget about trying to kasher it for Passover. Almost all dishwashers have parts in them that cannot be kashered at all (e.g. plastic). The same goes for getting a dishwasher used for non-kosher foods (you might as well get a new one) or if you are thinking about trying to switch a kosher meat dishwasher into a milk one or visa versa(you should forget about that too). Unless someone more knowledgeable cares to correct me, you can't kasher most used dishwashers at all. Reply

Anonymous Plymouth, USA April 17, 2011

Dishwasher Can a dishwasher be koshered for Passove? I have two dishwashers - one for meat and another one for dairy. They both have sanitizer settings to heat the water to boiling. Reply

Menachem Posner for Montreal, Quebec March 2, 2011

RE: Glass Please have a look at Can Glass Be Koshered for Passover for a discussion of this question. Reply

Anonymous Tel Aviv, Israel March 1, 2011

Glass Can one use kitchen utensils made of glass - such as plates, glasses etc? Reply

Aviyah Far Rockaway, NY March 29, 2010

Missing the Point... Just shortly, it seems like some people here are missing the point. To come up with ideas such as chametz on the surface of a utensil being the worry is kind of like self-medicating in the dose you feel is correct rather than what the doctor says. In reading this article, you will find that chametz is found not only on the outside of your spoon, pan, sink, or oven/ stove, but WITHIN these things as well. Heat during use transfers actual chametz into the metal, glass, etc.. This is a simple scientific/ physical fact...our wise rabbis have know about it for thousands of years. Another important fact is also found in the article: the way to remove chametz is through the same method which it entered; through the same type of heat source (i.e. boiling liquid or super-heating until red-hot). Before making up our own prescriptions, it might be a good idea to listen to the doctor/ rabbi! Reply

Naamah Chicago, IL/USA March 25, 2010

Koshering ovens/microwaves Sorry, Kevin you are incorrect.
Unless you eat military MREs out of a packet, almost all of your utensils and cooking equipment have potential chametz on them.
Yes, even dishwashers (which not everyone owns) can leave miniscule chametz on them if you dont scrub very and pay attention very carefully.
Most people also put the utensils away in areas such as kitchen drawers which may, throughout the year, easily get dust from the kitchen (which likely contains chametz) in it.
Havn't you ever reached in a drawer or cabinet to get a cup or fork while you were also cooking in the room? That's chamtez contamination.

Food may splash, spill onto stovetops.
Particles of Food (esp. food cooked directly on the racks such as pizza) falls to floor of ovens fairly often.
In microwaves, food often gets steamy, carrying tiny microbes of the food onto the surface of the inside of it.

Thus, chametz needs to be cleaned off! Reply

Kevin April 13, 2009

Microwave While I disagree with koshering anything, simply for the reason that washing machines clean off the chametz perfectly fine, koshering ovens and microwaves makes no sense. The food is never touched by the vessel itself. If you're worried about chametz falling in, then cover your food with foil in an oven or a lid in the microwave...

The main idea behind all this koshering is relatively ridiculous. If there's chametz on your utencils after going through a dish washer, you need to either clean them better in the dish washer or get better utensils (food stuck to utensils is not hygenic..) Reply

Anonymous pasadena, ca April 7, 2009

koshering a microwave over is it possible to kasher a microwave over for Passover? Reply

Anonymous London, England April 6, 2009

glass you do not say if and how to kosher glass/ toughened glass Reply via April 24, 2007

Editor's Response: 1. The author of this article wants to insure that all part of the utensil touches boiling water. If one has a very big utensil to be koshered, he might have to "push" it in, perhaps causing that one point of this utensil is being pushed against the side of the pot, causing it never to be touched by the boiling water.
The best solution for this, especially when you have many small utensils in the pot, is to shake the pot so that things move around and the boiling water can reach all surfaces.
2. Any pot can be used to kosher utensils for Passover. Reply

Bracha April 1, 2007

How can the utensil not touch the sides of the pot? If it does touch the sides of the pot, does it mean it has not been kashered?

And also can you use any kosher for passover utensil to remove the thing you're kashering inside a chometz pot? Reply

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