Question: Must countertops and sinks be kashered for Pesach?
Answer: While the major Kashrus organizations seem to say yes, R. Yitzchak Abadi’s view is that it is not necessary. He writes as follows:
שיש מטבח וכיורים או שולחנות... ידיחם היטב ואין צריכים הגעלה ברותחים.
Countertops, sinks, and tables… one should wash them well, and they do not require purging with hot water.
I wish to explore the basis of his ruling and how it might be justified, while presenting a general overview of the halachos of the transference non-kosher flavor into kosher food in general.
Flavor Is Like Substance
To understand what is going on here, we first must understand a few more basic things. First, who says a utensil such can be rendered not kosher in the first place? After all, it’s just a utensil. The answer to this question is that it is derived from a couple of verses in the Torah. The Jews had just won their battle against the Midianites, and they had taken plenty of spoils. Among these spoils were eating and cooking utensils. Regarding these utensils they were commanded as follows:
אַךְ אֶת הַזָּהָב וְאֶת הַכָּסֶף אֶת הַנְּחֹשֶׁת אֶת הַבַּרְזֶל אֶת הַבְּדִיל וְאֶת הָעֹפָרֶת. כָּל דָּבָר אֲשֶׁר יָבֹא בָאֵשׁ תַּעֲבִירוּ בָאֵשׁ וְטָהֵר אַךְ בְּמֵי נִדָּה יִתְחַטָּא וְכֹל אֲשֶׁר לֹא יָבֹא בָּאֵשׁ תַּעֲבִירוּ בַמָּיִם.
Gold, silver, bronze, iron, tin, lead and anything else that can withstand fire must be put through the fire, and then it will be clean. But it must also be purified with the water of cleansing. And whatever cannot withstand fire must be put through that water.
You may have noticed that this is actually the source for kashering non-kosher utensils. But what else is implicit in this command? It is understood that the reasoning behind the command was that flavor is like substance, or טעם כעיקר. Since a certain amount of non-kosher flavor is lodged in the pot, and flavor is like substance, the pot is rendered not kosher until it is purged of that flavor, because otherwise it will emit the non-kosher flavor – which is equal to non-kosher substance – into the next thing you cook in the pot. What kashering achieves is a significant purging of the non-kosher flavor in the utensil.
Transference of flavor
In consideration of this, various discussions have emerged in the Talmud and its commentaries as to what can cause transference of flavor. The basic rule is: Two cold things will generally not transfer flavor from one to another, but two hot things will. This leads us to three inquiries:
1. How hot is called hot?
2. How much flavor gets transferred, and how much is a problem?
3. What if one thing is hot and the other thing is cold?
1. How Hot Is Called Hot
According to normative halacha, heat is only presumed to have transferred flavor if the hot item was a) either on the heating element or in a pot that was on the heating element; and b) it was scalding hot at the time of contact.
This means that even if something is boiling hot, if it is not on the fire or in a utensil that was, it is not assumed to retain the full strength of its heat, and therefore it will not transfer a significant amount of flavor. Therefore normative halacha says that any hot item placed in a “second utensil,” i.e. a utensil that was not on the fire, is halachically cold.
There are those who wish to say that as long as something is scalding hot it can transfer flavor, even without the first qualification. However as noted by the Aruch Hashulchan the consensus of Poskim is that without both qualifications there is never a presumption of transference, and included in this consensus are the Shulchan Aruch and Rema.
There is one possible exception to this rule, and that is a solid food item. Maharshal is of the opinion that a solid food item, such as a piece of meat, can retain its heat and transfer flavor as long as it is scalding hot, even after it has been placed into a second utensil. The Magen Avraham accepts this view, and Shach leans toward it as well. However Rema disputes this and holds that the two qualifications must always be there, otherwise we never presume transference. Some are unsure about the halacha and follow Rema when it is a question of a rabbinic prohibition and Maharshal when it is a question of a biblical prohibition, but according to Rabbi Abadi the halacha is in accordance with the Rema, and so at the end of the day, both qualifications are always required in order to presume transference of flavor.
2. How Much Flavor Gets Transferred and How Much Is A Problem
A. The rule is that nothing transfers much flavor without liquid. When something is cooked with liquid the flavor can get evenly distributed. In this case we presume the worst: that the entire volume’s worth of flavor of the item has been transferred. In other words, if an ounce of meat was cooked in a pot of milk, we say that we must assume that an ounce of meat-flavor is in the milk.
B. A fatty piece of meat is also like something submerged in liquid, because the fat achieves the same goal when heated.
In the above two cases, if the non-kosher flavor transferred is less than 1:60 to the rest of the food, the flavor transferred is considered insignificant, and the food remains kosher.
C. Two solid food items that are not fatty can only transfer flavor within each others’ outer layers. Therefore once the outer layer is peeled or cut off (called netila), the item retains its kosher status. However Rema maintains that since it is not clear what is called fatty and not fatty, the general practice is to require 60:1 for anything that might possibly be called fatty.
D. Two completely dry, solid items, such as two pots, will not presumably transfer any flavor (unless there is liquid between them – in which case we are back to A).
3. What If One Thing Is Hot and the Other Thing Is Cold
Here comes the rule of tata’ah gavar, the bottom wins. Meaning, if the bottom is hot (according to the qualifications of 1), it presumably will heat up whatever is placed onto it and thus flavors will be transferred both ways, and if the bottom is cold, it presumably will cool off what is placed onto it and thus no flavors will be transferred. There is one qualification in this latter case though, and that is that since presumably it takes more than a second to cool off, it is presumed that a very thin layer of each side has absorbed flavor from the other, called kelipa, but that’s all.
I have treated the specifics of this rule extensively in my last post.
When two things are side by side, they are treated as though neither is on bottom, and no flavor is presumed transferred, besides for kelipa.
One More Avenue of Heter
Nosein ta’am lifgam. Something which gives off a bad flavor. Even non-kosher substance is only prohibited so long as it is fitting for human consumption. In a similar way, non-kosher flavor does not render the food that absorbs it non-kosher if as a result of the transference the food now tastes less pleasant.
One major application of this rule is that with utensils, all flavor that has been absorbed for longer than twenty-four hours is presumed unpleasant flavor. When one is in doubt, the halacha is that one may always assume that a specific utensil has not been used within this time period.
Now Back To Sinks and Countertops… Finally
Right, that’s what all this was leading up to. Based on all of the above, we can say as follows:
A. It is unlikely that some chametz has fallen from the fire or from a utensil that was on the fire, directly into the sink. Therefore the sink is at most a keli sheini, a second utensil, in which we have established there is no transference of flavor. But here’s the clincher: Even if it has happened – what is the likelihood of something falling in on Pesach under such circumstances, and someone eating it?
B. Moreover, there is certainly no reason to assume that the entirety or even the majority of the sink or countertop has been hit by scalding chametz. Since we are dealing with a case of the bottom being cold (the sink and countertops are never first utensils), we know that nothing more than kelipa could possibly have been absorbed. It is therefore clear that at most, there are a few kelipa spots around the sink and countertop areas, but it is unknown where. In this case we may rely on the general principle of bitul berov, nullification by the greater part, and say that since the greater part is kosher and the lesser part is not discernible, the entire area is kosher.
C. Any flavor transferred would only be unpleasant, as it can be assumed that no chametz has been absorbed within the previous twenty-four hours.
And so, in really short, Rabbi Abadi writes this in the footnote of his pesak:
כיון דאין בליעה אלא מכלי ראשון וזה אינו שכיח, ועוד דהוא תתאה ואינו בולע אלא כדי קליפה, ומן הסתם לאו בן יומו ונותן טעם לפגם, וגם אם כן ספק הוא היכן בלע.
 אור יצחק ח"ב קונטרס אחרון הלכות פסח כב:ב
 Numbers 31:22-23
 There is a lot more to discuss on the subject. Some understand that the derivation is from someplace else, and some opine that it is biblically derived at all. The consensus, however, is that it is a biblically derived law. I have treated the matter extensively here: http://beismedrash.blogspot.com/2011/07/blog-post.html
 The specific temperature of this is the subject to debate. The term used is “heat that would scald the hand,” or “heat that the hand would jump away from [due to being scalded].”
 See Shulchan Aruch Y.D. §105:2
 See Taz and Shach ad loc.
 Ibid. se’if 19
 Cited in above Shach
 O.C. 218:45
 Shulchan Aruch Y.D. ibid. 3
 See Chullin 97b – this is a chumra in a matter of doubt that is not subject to normal leniencies for a number of technical reasons.
 Shulchan Aruch ibid. 5
 See Pesachim 76a
 Rema ibid. 3
 See Y.D. §103 et al and my treatment of the subject here:
 See Avodah Zarah 75b-76a
 This argument is advanced by R. Akiva Eiger on Shulchan Aruch ibid. note 11.