The end of parshas Balak includes a reference to the laws of kashrus:
Question #1: Sentimental China
“A family is in the process of kashering their home for the first time, and they own an expensive and sentimental, but treif, set of china. Is there any way that they can avoid throwing it away?”
Question #2: No Bologna
“I own an expensive set of fleishig china that I do not use, and, frankly, I desperately need money for other things now. Someone is interested in paying top price for this set because it matches their milchig china. Is there any way I can kasher it and sell it to them, and they may use it for milchig?”
Question #3: Hungary on Pesach
“Help! I just completed cooking the seudos for the first days of Pesach, and I realize now that I used a pot that was used once, more than two years ago, for chometz. Do I have to throw out all the food I made? I have no idea when I am going to have time to make the seudos again!”
Every one of the she’eilos mentioned above shows up in one of the classic works of responsa that I will be quoting in the course of this article. They all touch on the status of food equipment that has not been used for twelve months. In order to have more information with which to understand this topic, I must first introduce some halachic background.
When food is cooked in a pot or other equipment, halacha assumes that some “taste,” of the food remains in the walls of the pot, even after the pot has been scrubbed completely clean. We are concerned that this will add flavor to the food cooked subsequently in that pot. This is the basis for requiring that we kasher treif pots, because the kashering process removes the residual taste.
Until the pot is kashered
Once twenty-four hours have passed since the food was cooked, the residual taste in the vessel spoils and is now categorized as nosein taam lifgam, a halachic term meaning thatthe taste that remains is unpleasant. Something is considered nosein taam lifgam even if it is only mildly distasteful.
The Gemara (Avodah Zarah 67b) cites a dispute between tana’im whether nosein taam lifgam is permitted or prohibited. The Mishnah (Avodah Zarah 65b) rules that nosein taam lifgam is permitted. This is the conclusion of the Gemara in several places (Avodah Zarah 36a, 38b, 39b, 65b, 67b) and also the conclusion of the halachic authorities (Rambam, Hilchos Ma’achalos Asuros 17:2; Shulchan Aruch, Yoreh Deah 103:5; 122:6). This means that, although it is prohibited to eat a food that includes a pleasant taste or residue of non-kosher, when the non-kosher food provides a less than appetizing flavor, the food is permitted.
Here is an example that bears out this rule. Glycerin (sometimes called glycerol), which is frequently manufactured from non-kosher animal fat, is often used as an ingredient in foods because, in addition to its other properties, it also adds a sweet flavor to the product. Therefore, when non-kosher glycerin is used in an otherwise kosher product, as I once found in a donut glaze, the product — in this case the donuts — are non-kosher.
On the other hand, if the ingredient adds an unpleasant taste, the finished product remains kosher.
Because of the halachic conclusion that nosein taam lifgam is permitted, min haTorah one would be allowed to use a treif pot once twenty-four hours have passed since it was last used. As mentioned above, at this point the absorbed flavor is considered spoiled, nosein taam lifgam. The reason that we are required to kasher equipment that contains nosein taam lifgam is because of a rabbinic injunction. This is because of concern that someone might forget and cook with a pot that was used the same day for treif, which might result in the consumption of prohibited food (Avodah Zarah 75b).
Chometz is exceptional
The above discussion regarding the rules of nosein taam lifgam is true regarding use of a pot in which non-kosher food was cooked. However, regarding chometz, the prohibition is stricter. Ashkenazim rule that nosein taam lifgam is prohibited in regard to Pesach products. Why is the halacha stricter regarding Pesach? Nosein taam lifgam still qualifies as a remnant of non-kosher food; it is permitted because it does not render a positive taste. However, regarding Pesach, we rule that even a minuscule percentage of chometz is prohibited. Thus, if a chometz–dik pot was used to cook on Pesach, even in error, the food is prohibited.
Fleishig to milchig
The rules governing the use of fleishig equipment that was used for milchig and vice versa are similar to the rules that apply to treif equipment, and not the stricter rules that apply to chometz–dik equipment used on Pesach. Someone who cooks or heats meat and dairy in the same vessel, on the same day, creates a prohibited mix of meat and milk. If the fleishig equipment had not been used the same day for meat, the meat flavor imparted to the dairy product is nosein taam lifgam. Although the pot must be kashered, since it now contains both milk and meat residue, the dairy food cooked in it remains kosher (Shulchan Aruch, Yoreh Deah 93:1). The same is true regarding dairy equipment used to prepare fleishig.
Kashering from fleishig to milchig
Although non-kosher equipment can usually be kashered to make it kosher, and chometz–dik equipment can usually be kashered to make it kosher for Passover, there is a longstanding custom not to kasher fleishig equipment to use as milchig, and vice versa (Magen Avraham 509:11). The reason for this custom is because if a person regularly koshers his pots or other equipment from milchig to fleishig and back again, he will eventually make a mistake and use them for the wrong type of food without kashering them first (Shu’t Igros Moshe, Yoreh Deah 1:43). By the way, it is accepted that someone who kashered their fleishig pot for Pesach may now decide to use it for milchig and vice versa.
We need one more piece of information before we begin to discuss the laws of equipment that has not been used for twelve months. That is to note that there is equipment that cannot usually be kashered. The Gemara teaches that we cannot kasher earthenware equipment, since once the non-kosher residue is absorbed into its walls, it will never come out. (Some authorities permit kashering earthenware or china, which is halachically similar, three times, although this heter is not usually relied upon. A discussion on this point will need to be left for a different time.)
Now that we have had an introduction, we can discuss whether anything changes twelve months after food was cooked. Chazal created a prohibition, called stam yeinam, which prohibits consumption, and, at times, even use, of wine and grape juice produced by a non-Jew. Halachically, there is no difference between wine and grape juice. Notwithstanding the prohibition against using equipment that was once used for non-kosher, we find a leniency that equipment used to produce non-kosher wine may be used after twelve months have transpired. The equipment used by a gentile to crush the juice out of the grapes, or to store the wine or grape juice is also prohibited. This means that we must assume that this equipment still contains taste of the prohibited grape juice.
The Gemara (Avodah Zarah 34a) rules that the grape skins, seeds and sediment left over after a gentile crushed out the juice are prohibited both for consumption and for benefit. This is because non-kosher grape juice is absorbed into the skins, seeds and sediment. However, after they have been allowed to dry for twelve months, whatever non-kosher taste was left in the skins, seeds and sediment are gone, and it is permitted to use and even eat them. Similarly, once twelve months have transpired since last use, the equipment used to process or store the non-kosher juice also becomes permitted. Thus, the Gemara rules that the jugs, flasks and earthenware vessels used to store non-kosher wine are prohibited for twelve months, but may be used once twelve months have elapsed since their last use. The conclusions of this Gemara are codified in the Shulchan Aruch (Yoreh Deah 135:16). The process of allowing twelve months to transpire and then permit the leftovers is called yishun.
Several common products are permitted because of this halacha. One example is a wine derivative called tartaric acid, an organic compound with many practical usages. Among its food uses is in beverages, as a flavor enhancer and as baking powder. It is commonly considered kosher, notwithstanding that it is a by-product of non-kosher wine. (It should have a hechsher since it can be produced in ways that are non-kosher.)
It is important to note that this method of kashering, i.e., of waiting twelve months, is mentioned in the Gemara only with reference to kashering after the use of non-kosher wine. The halachic authorities debate whether this method of kashering may be used regarding other prohibitions, and this is the starting point for us to address our opening questions.
Hungry on Pesach
“Help! I just completed cooking the seudos for the first days of Pesach, and I realize now that I used a pot that was used once, more than two years ago, for chometz. Do I have to throw out all the food I made? I have no idea when I am going to have time to make the seudos again!” It would seem that there is no hope for this hardworking housewife, and indeed all her efforts are for naught. However, let us examine an actual case and discover that not everyone agrees.
A very prominent eighteenth-century halachic authority, the Chacham Tzvi, was asked this question: On Pesach, someone mistakenly cooked food in a pot that had been used once, two years before, for chometz. Since Ashkenazim rule that even nosein taam lifgam is prohibited on Pesach, it would seem that the food cooked on Pesach in this pot is prohibited, and this was indeed what some of those involved assumed. However, the Chacham Tzvi contended that the food cooked in this pot is permitted, because he drew a distinction between nosein taam lifgam after 24 hours, and yishun after 12 months. He notes that grape juice absorbed into the vessels or the remaining seeds and skins is prohibited, even for benefit, for up to 12 months, yet after 12 months it becomes permitted. Thus, we see that even the actual wine becomes permitted, because after twelve months it dries out completely and there is no residual taste. It must certainly be true, reasons the Chacham Tzvi, that chometz flavor absorbed into a pot or other vessel must completely dissipate by twelve months after use and that no residual taste is left (Shu’t Chacham Tzvi #75, 80; cited by Pischei Teshuvah, Yoreh Deah 122:3).
Notwithstanding this reasoning, the Chacham Tzvi did not permit using treif equipment without kashering it, even when twelve months transpired since its last use. He explains that since Chazal prohibited use of treif equipment even when the product now being manufactured will be kosher, no distinction was made whether more than a year transpired since its last use — in all instances, one must kasher the vessel before use and not rely on the yishun that transpires after twelve months. However, after the fact, the Chacham Tzvi permitted the food prepared by Mrs. Hardworking in a pot that had been used for chometz more than twelve months before.
About a century after the Chacham Tzvi penned his responsum, we find a debate among halachic authorities that will be germane to a different one of our opening questions.
Someone purchased non-kosher earthenware vessels that had not been used for twelve months. He would suffer major financial loss if he could not use them or sell them to someone Jewish. Rav Michel, the rav of Lifna, felt that the Jewish purchaser could follow a lenient approach and use the vessels on the basis of the fact that, after twelve months, no prohibited residue remains in the dishes. However, Rav Michel did not want to assume responsibility for the ruling without discussing it with the renowned sage, Rabbi Akiva Eiger (Shu’t Rabbi Akiva Eiger 1:43).
Rabbi Akiva Eiger rejected this approach. First of all, he noted that the Chacham Tzvi, himself, did not permit cooking in vessels aged twelve months since last use, only permitting the product that was cooked in those pots.
Secondly, Rabbi Akiva Eiger disputed the Chacham Tzvi’s approach that the concept of yishun applies to anything other than wine. Rabbi Akiva Eiger writes that, among the rishonim, he found the following explanation of yishun: The Rashba writes that the concept of yishun applies only to wine vessels, and the reason is because no remnant of the wine is left since it has dried out (Shu’t Harashba 1:575). Rabbi Akiva Eiger writes that the only other rishon he found who explained how yishun works also held the same as the Rashba. This means that the kashering method known as yishun applies only for non-kosher wine, but to no other prohibitions. Since Rabbi Akiva Eiger found no rishon who agreed with the Chacham Tzvi, he was unwilling to accept this heter. In his opinion, the food cooked on Pesach by Mrs. Hardworking is chometz–dik and must be discarded.
At this point, let us examine a different one of our opening questions:
“A family is in the process of kashering their home for the first time, and they own an expensive, but treif, set of china. Is there anyway that they can avoid throwing it away?”
Rav Moshe Feinstein was asked this exact question (Shu’t Igros Moshe, Yoreh Deah 2:46). Rabbi Shmuel Weller, a rav in Fort Wayne, Indiana, asked Rav Moshe about a family that, under his influence, had recently decided to keep kosher. The question is that they have an expensive set of porcelain dishes that they have not used for over a year and they do not want to throw it away. Is there any method whereby they may still use it? Rav Moshe writes that, because of the principle of takanas hashavim — which means that to encourage people who want to do teshuvah we are lenient in halachic rules — one could be lenient. The idea is that although Chazal prohibited use of an eino ben yomo, they prohibited it only because there is still residual flavor in the vessel, although the flavor is permitted. Once twelve months have passed, the Chacham Tzvi held that there is no residual flavor left at all. Although the Chacham Tzvi, himself, prohibited the vessels for a different reason, Rav Moshe contends that there is a basis for a heter. (See also Shu’t Noda Biyehudah, Yoreh Deah 2:51.)
Rav Moshe notes that there are other reasons that one could apply to permit kashering this china, and he therefore rules that one may permit the use of the china by kashering it three times. Because of space considerations, the other reasons, as well as the explanation why kashering three times helps, will have to be left for a different time.
At this point, let us refer again to a different one of our opening questions: “I own an expensive set of fleishig china that I do not use, and, frankly, I desperately need money for other things now. Someone is interested in paying top price for this set because it matches their milchig china. Is there anyway I can kasher it and sell it to them, and they may use it for milchig?”
This question presents two problems:
(1) Is there any way to remove the residual fleishig flavor and kasher the china?
(2) Is it permitted to kasher anything from fleishig to milchig?
In a responsum to Rav Zelig Portman, Rav Moshe Feinstein (Shu’t Igros Moshe, Yoreh Deah 1:43) discusses this question.
We will take these two questions in reverse order. As I mentioned earlier, the Magen Avraham (509:11) reports that there is an accepted minhag not to kasher fleishig equipment in order to use it for milchig, and vice versa. Wouldn’t changing the use of this china violate the minhag?
Rav Moshe explains that the reason for this minhag is to avoid someone using the same pot, or other equipment, all the time by simply kashering it every time he needs to switch from milchig to fleishig. The obvious problem is that, eventually, he will make a mistake and forget to kasher the piece of equipment before using it.
Rav Moshe therefore suggests that the custom of the Magen Avraham applies only to a person who actually used the equipment for fleishig; this person may not kasher it to use for milchig. However, someone who never used it for fleishig would not be included in the minhag.
Regarding the first question, Rav Moshe concludes that, since twelve months have passed since the china was last used for fleishig, one may kasher it.
The Gemara teaches that the rabbinic laws are dearer to Hashem than are the laws of the Written Torah. In this context, we understand that Chazal established many rules to protect the Jewish people from violating the Torah’s laws of kashrus. This article has served as an introduction to one aspect of the laws of kashrus that relates to utensils. Not only is the food that a Jew eats required to be given special care, but also the equipment with which he prepares that food. We should always hope and pray that the food we eat fulfills all the halachos that the Torah commands us.