Nullification: Difference between revisions

# There is a dispute whether nullification requires that there is a majority in quantity of permitted pieces as well as majority of volume of permitted pieces<ref>Chinuch Bet Yehuda 80 cited by Pitchei Teshuva YD 109:2</ref> or merely that one needs a majority in quantity of permitted pieces.<ref>Chazon Ish YD 37:20. See Rashba 1:272 who implies that majority of volume is all that is necessary.</ref>

# If a mixture has solids that dissolved completely they are treated like liquid mixtures.<ref>Shulchan Aruch 104:1</ref>

# If a mixture has solids that are recognizably separate from the liquid the mixture is treated as both a mixture of solids and liquids. In order to permit eating the liquid there needs to be sixty in the whole mixture in comparison to the forbidden ingredients. If there is a solid non-kosher ingredient and it is recognizable it needs to be removed. If it isn't recognizable and there are other comparable kosher solid ingredients if there are a majority of the solid ingredients the solids can be eaten if there is also sixty in the entire mixture compared to the forbidden ingredients. If there isn't majority the solid ingredients are forbidden even if there is sixty in the entire mixture compared to the forbidden ingredients.<ref>Shach 109:4</ref>

# If the solid pieces of non-kosher in the liquid mixture are crushed up into small pieces but are recognizable they should be strained out. If that is impossible some say that it is forbidden.<ref>Shulchan Aruch 104:1. Rama limits it to a sheretz but Taz 104:2 argues. Ran Avoda Zara 32b s.v. hahu agrees with Tosfot that it is relevant to all prohibitions. He asks two questions on Rashi. 1) Why doesn't chatzi shiur make it asur for all prohibitions? 2) Why couldn't they strain out the solids?</ref>

*Rava in gemara Chullin 97a states that one can rely on the testimony of a non-Jewish chef that a mixture of meat and a bit of milk doesn't have any dairy taste in it to permit it to a Jew. Concludes the gemara, if there no chef around or it is a mixture of similar items and it is impossible to taste the forbidden item specifically, one needs nullification of 60. (a) Rashi (Chullin 98a s.v. beshishim) implies that even if there's no taste of the forbidden ingredient still the mixture is forbidden unless there is also nullification of 60. (b) Similarly, the Ramban Chullin 98a s.v. kol holds that if the forbidden food dissolved into the permitted food it is nullified with 60 and not the taste of a chef. Yet, if the forbidden food was removed from the mixture but its taste remains it is nullified with the taste of a chef even if that's less than 60. (c) However, the Tosfot Chullin 99a s.v. elah and Rosh (Chullin 7:29) argue that if the non-Jew doesn't taste the forbidden ingredient it is permitted even if there isn't nullification of 60. (d) The Bet Yosef YD 98:1 understands that the Rambam (Machalot Asurot 15) thinks if there's an option to ask a non-Jewish chef one should and if he says that there's a forbidden taste, it is forbidden even if there's nullification of 60 and if he says that there's no forbidden taste it is permitted even if there's not nullification of 60.  

# If there's a mixture of like tasting ingredients and unlike tasting ingredients and the forbidden ingredient isn't recognizable. If (1) the volume of the like-tasting ingredient is greater than the volume of the forbidden ingredient and (2) the volume of the permitted ingredients, both those of similar and dissimilar tastes, is sixty times that of the forbidden ingredient the mixture is permitted.<ref>The Shulchan Aruch YD 98:2 is lenient even if there's a doubt if there's sixty but the Shach 98:6 disagrees because it is a Biblical issue so one couldn't be lenient in a case of doubt. However, if there's a certain sixty that is permitted according to everyone. Pri Megadim M"Z 98:3 clarifies this as well.</ref>

# If there's a mixture of like tasting ingredients and unlike tasting ingredients and the forbidden ingredient isn't recognizable. If (1) the volume of the like-tasting ingredient is equal to or less than the volume of the forbidden ingredient but (2) the volume of the permitted ingredients, both those of similar and dissimilar tastes, is sixty times that of the forbidden ingredient, some poskim hold that the the mixture is permitted, while others argue.<ref>The Pri Megadim (Shaar Hataarovet 3:1 s.v. vnistapakti) has a doubt about a case in which there's 1/2 a piece of nevelah meat, 1/2 a piece of kosher meat, and 30 pieces of vegetables. On the one hand, one will taste the taste of meat in the 30 pieces of vegetables and since the taste of meat is comprised of both the kosher and non-Kosher it is forbidden. Yet, the Kereti assumes that this is permitted since the taste of the non-Kosher meat dispersed into sixty times its volume of Kosher ingredients. The Pri Megadim proves from the Taz OC 318:15 that it is forbidden. In OC M"Z 318:15 he points out that the Rama and Eliya Rabba seem to be lenient on this question as long as the forbidden ingredient wasn't sufficient on its own to give a taste because of Zeh Vezeh Gorem. Likutei Megadim quotes the Maharam Shik YD 114 who says that it is permitted since there's no way that something permitted can cause Chozer Vneer from the gemara Bechorot 20a. But there would be less than 60 it would be forbidden Biblically since the meat is tasted. He also quotes the Bet Yehuda 98:2 s.v. nireh who is lenient since the taste of the forbidden ingredient is masked by the permitted ingredient.</ref>

# Once a solid food becomes forbidden by a transfer of taste it can never revert to becoming permitted again. That is, even if it is later cooked with sixty times its measure and is nullified, that piece remains forbidden.<ref>The Rashba holds that once a piece of food becomes forbidden it can never revert to become permitted. Tur 106:1 disagrees. Shulchan Aruch Y.D. 106:1 accepts the Rashba. However, in Y.D. 92:4 the Shulchan Aruch uses the language of the Tur. Taz 92:10 and Gra 92:16 point out this contradiction but side with the Rashba. Shach 92:11 reads the Shulchan Aruch 92:4 in light of 106:1. Therefore, the conclusion of the poskim is like the Rashba (Horah Brurah 92:32).</ref>

# Once a food becomes forbidden by a transfer of taste in order to nullify it when it is part of a mixture, according to Ashkenazim, one needs to measure sixty times the entire volume of that food. This concept is known as ''Chaticha Naaseh Nevelah'' or ''Chanan''.<ref>Gemara Chullin 108b, Rama 92:4. Taz 92:11 points out that many poskim hold that this applies even to a rabbinic prohibition. Badei Hashulchan 92:64 agrees. Taz 87:2 implies the same.</ref> Sephardim only hold of this concept by meat and milk but for other prohibitions one only ever needs to nullify the volume of the original prohibition.<ref>Shulchan Aruch Y.D. 92:4, Horah Brurah 92:34</ref>

# Chanan only applies if one piece became forbidden before the rest of the mixture. That can happen if one piece was completely out of the gravy and something forbidden fell upon it (''Chutz Mrotev''). Another method of chanan is where two pieces are connected such as fat and an inner organ or the heart and meat nearby (''Isur Davuk'').<ref>Rama 92:4</ref>

# Items for which nullification is ineffective because it is significant can be nullified when it falls into one mixture and one of that mixture falls into a second mixture and then one of the second mixture falls into a third mixture.<ref>Shulchan Aruch YD 110:8

* Zevachim 74a cites a dispute between rav and shmuel whether two rov’s are sufficient to permit  a prohibition for which bitul is ineffective. Rav is lenient, while Shmuel is strict for Avoda Zara. Rambam Machalot Asurot 8:11 follows Rav unlike the Raavad who follows Shmuel.  

* Rambam seemingly contradicts himself whether a second or third mixture is necessary. Kesef Mishna Avoda Zara 7:10 answers for the Rambam that the nullification of rimonim of trumah might be taken lightly so we're stricter. Alternatively it is like a dvar sheyesh lo matirin since there's something that can be done to solve the issue if they were broken. However, the Gra answers that the Rambam thinks that you need three tarovot whenever we’re discussing something that isn’t batel since the rabbis treated the first tarovet as though it was certainly forbidden. Then you need another two mixtures to be lenient. However, the reason that avoda zara isn’t nullified is because safek avoda zara is forbidden and as such a double rov is sufficient.  

* Rashba holds that they’re permitted in the second mixture Bet Yosef posts that even according to the Rashba one couldn’t eat all of the pieces of the second mixture simultaneously because of his opinion cited in S”A 109:1.  

* Rashi holds that the second mixture is forbidden unless something of it falls out into another mixture. That is because Rashi a”z 74a generally holds that bitul requires something to be removed for the mixture. Birchat Hazevach explains rashi similarly. However, Chok Natan explains that Rashi holds that unless there’s another mixture it is a problem since the third mixture creates another safek.

* Tosfot posits that really you can be lenient with the second mixture you just can’t eat the entire thing. However, if there are is a third mixture you can benefit from all of them.  

* Rashi kitvei yad writes that the second mixture is completely permitted.

* Shulchan Aruch YD 110:8 rules that a third mixture is necessary like Rambam Machalot Asurot 8:11. Shach 110:50 writes that in a case of loss one can follow Tosfot.</ref>

# Produce of Israel from the Shemitta (Sabbatical year) can’t be nullified unless it is mixed with a different type of food (different in name) in which case Bitul BeShishim is effective. <ref>Rambam Machalot Assurot 15:8. See Encyclopedia Talmudit s.v. Bitul Isurim which quotes a machloket rishonim if the rule that shemitta produce isn't nullified in any amount whether it applies only before the time of biyur (Ran Nedarim 58a, Raavad Machalot Asurot 15:6, Shemita 7:3), only after the time of biyur (Rash and Rav Shemitta 7:7) or both (Rambam). The Ran explains that Shemitta produce isn't nullified because it could all be eaten with Shemitta holiness and is a dvar sheyesh lo matirin.</ref>

# Something which is forbidden to someone and for others would be considered permitted after a time according to some is considered dvar sheyesh lo matirin, while according to many isn't considered dvar sheyesh lo matirin for the person for whom it is forbidden. For example, if something was intentionally cooked on Shabbat and was mixed in another food it is a dispute whether that considered dvar sheyesh lo matirin.<ref>The Rama 102:4 quotes Rabbenu Yerucham that it isn't considered dvar sheyesh lo matirin if for someone else it is permitted after a time. However, the Magen Avraham 318:2 argues since it is permitted for someone else after a time and it is like bikkurim. However, the Chavot Daat 102 disputes that point. Mishna Brurah 318:5 and Badei Hashulchan 102:54 cite the dispute without any resolution.</ref>

# Foods use to serve Avoda Zara can't be nullified.<ref>Shulchan Aruch YD 140</ref>

# Wine poured to Avoda Zara can't be nullified.<ref>Rambam Machalot Asurot 15:6</ref>

# A complete creature or limb isn't nullified even in a mixture of foods that have a dissimilar taste.<ref>Darkei Moshe 100 cites the Isur Veheter who says that biryah is permitted if it is mixed with ingredients of dissimilar tastes. Shulchan Aruch 100:3 rules like the Rashba that biryah isn't nullified.</ref>

# There are four conditions for a prohibition to be considered a biryah: 1) It was a living creature,<ref>Macot 16a, Rosh Chullin 7:33, Shulchan Aruch YD 100:1</ref> 2) It was forbidden from its creation,<ref>Rashi Chullin 102b s.v. tameh</ref> 3) It is complete,<ref>Gemara Macot 16b, Tur 101:6 and Shulchan Aruch YD 100:1</ref> 4) It isn't called by its original name after it is cut.<ref>Rosh Chullin 7:33, Shulchan Aruch YD 100:1</ref>  

# Therefore, the following are considered a biryah: bugs, non-kosher birds, Gid Hanashah, Even Min Hachay, and an egg with a chick inside. Whereas a prohibited plants, Nevelah, Terefa, or Chelev aren't a biryah.<ref>Shulchan Aruch YD 100:1, Shach 100:4</ref>

# An egg with a blood spot isn't considered a biryah.<ref>Shach 100:2</ref>

# If there is a doubt if a food is kosher but it is certainly a biryah it isn't nullified. However, if there is a doubt if something is a biryah it is nullified.<Ref>Taz 100:1 writes that since biryah is only rabbinic it is considered permitted if there is a doubt if it is biryah. If it is a doubt if it is kosher it is considered non-kosher based on safek deoritta lchumra and then afterwards that question isn't revisited when considering it a biryah that isn't nullified (safek deoritta sh'nitgalgel lehiyot derabbanan).</ref>

# If the biryah is broken or split it is nullified. Some say that it could be nullified even while one is chewing.<ref>Chazon Ish YD 14(1):6 s.v. vshiur writes that even if a biryah is broken while it is being chewed it is nullified. [http://www.hebrewbooks.org/pdfpager.aspx?req=21547&st=&pgnum=283 Mechzeh Eliyahu 1:89] questions this.</ref>

# An egg nowadays is considered a dvar shebeminyan according to many poskim.<ref>Ohel Yakov Isur Vheter p. 505 quotes Rav Sheinberg and Rav Nevinsal that eggs today are considered a dvar shebeminyan since they are sold by number. However, Rav Reuven Feinstein holds that it isn't a dvar shebeminyan since they only sell in it as a dozen for convenience but that is merely a sign of its weight.</ref>

# A forbidden piece of meat or fish that is significant that can be used to honor a guest isn't nullified in any amount.<ref>Shulchan Aruch 101:1</ref> This applies to any prohibited item even if it is only rabbinically forbidden.<ref>Rama 101:1</ref>

# If there's a doubt if it can be used to honor a guest one can be lenient.<ref>Rama YD 101:1. Pri Megadim M"Z 101:2 asks how there could be a doubt if something is useful to honor a guest, it is ascertainable (see Shulchan Aruch YD 98:3). He quotes the Pri Toar 101:4 who answers that with respect to objective questions whether it is ascertainable it isn't a doubt but since this is a subjective question one could be in doubt.</ref>

# This rule only applies if the piece of meat or fish is forbidden in it of itself but not if it only absorbed a taste of something forbidden. The only exception is meat and milk which if combined each piece is completely forbidden in it of itself.<ref>Shulchan Aruch 101:2</ref>

# Meat that was a person wasn't watching and became forbidden because of [[Basar SheNitalem Min HaAyin]] is nullified in a majority.<ref>Rabbi Akiva Eiger 101:1 based on Shach Klalei Safek Safeka 110:19 that there is no issue of Chaticha Hareuya Lhitchabed for meat that wasn't watched which is a chumra derabbanan and not like other derabbanan's.</ref>

# A piece of cheese can be significant and considered a chaticha hareuya lhitchabed.<ref>The Maharshal (Yam Shel Shlomo Kol Habasar 108 cited by Taz) writes that cheese isn’t a chaticha hareuya lhitchabed since a person can’t eat so much of it until he gets full. Also some people don’t like it at all. Therefore, it isn’t a chaticha hareuya lhitchabed. Taz 101:3 argues that cheese is a chaticha hareuya lhitchabed and it is evident in the Rashba (Torat Habayit 91a).</ref>

# Cheese that was made with teref rennet is not a chaticha hareuya lhitchabed.<ref>Torat Chatat 40:2, Taz 101:3, Nekudat Hakesef 101:1. Even though the Torat Chatat thought that the Isur Vheter was strict in this case the Nekudat Hakesef points out that Isur Vheter didn’t say that. Also, even though the Taz accused the Bach of saying that it is a chaticha hareuya lhitchabed the Nekudat Hakesef argues that the Bach never said it.</ref>

# Cheese that was made with teref milk is a chaticha hareuya lhitchabed.<ref>Nekudat Hakesef 101:1</ref>

# Cheese made with Kosher milk mixed with milk from a non-Kosher animal isn't a chaticha hareuya lhitchabed.<ref>Taz 101:3 explains that since the non-Kosher milk doesn't congeal into cheese but is just stuck in pockets in the cheese though non-kosher milk isn't considered significant.</ref>

# Cheese made by a non-Jew is a chaticha hareuya lhitchabed.<ref>The Isur Vheter 25:8 writes that cheese made by a goy is a chaticha hareuya lhitchabed since it was forbidden from the moment it was created. Rama in Torat Chatat 40:2 writes that if it is cheese made with kosher milk and teref rennet it isn’t a chaticha hareuya lhitchabed since it only absorbed the taste of something forbidden. Bach 101:2 argues with the Rama and concludes like the Isur Vheter that all cheese made by a non-Jew is a chaticha hareuya lhitchabed. However, the Nekudat Hakesef agrees with the Bach that any cheese made by a non-Jew is a chaticha hareuya lhitchabed.

* The Taz 101:3 distinguishes between when the cheese was made with hide of a nevelah that it is considered a chaticha hareuya lhitchabed since from the creation of the cheese it was forbidden and the cheese which was made by a non-Jew and there’s a concern that mixed in is non-kosher milk that it isn’t a chaticha hareuya lhitchabed. </ref>

# Tagatose in diet slurpees is nullified. Therefore, some poskim would allow eating it with meat. Yet, others hold that the slurpee is dairy and as such the kashrut organizations mark it as dairy (see [https://www.star-k.org/resource/list/1PR911FW/7-Eleven_Kosher_Slurpee#pepsirabbicharlop Star-K on Diet Pepsi]).<ref>Firstly, tagatose could be parve since it is a sugar processed from dairy (see [KosherVeyosher.com http://www.kosherveyosher.com/lactose-reb-elyashiv-teshuva.html] based on Rav Elyashiv in Kovetz Teshuvot 1:73). Secondly, the tagatose could be nullified in sixty since it is permitted (Shulchan Aruch YD 87:11).

* Radvaz 3:547 writes that it is forbidden to buy a product from a non-Jew if there’s something in it that was forbidden but was nullified. He admits though that it is permitted if it was just cooked in a pot that wasn’t used within 24 hours. He explains that it isn’t likely one is going to ask a non-Jew to cook in such a pot since it doesn't impart a good flavor. Yet it is a problem to buy the food which had non-Kosher mixed in since one may ask a non-Jew to do so. [Radvaz 1:580 is lenient to buy from a non-Jew safek orlah grapes mixed up and are nullified. Maybe this shows that the Radvaz would be lenient if there’s no option (haarot). Alternatively, there’s no issue of bitul isur lechatchila for something that is only a safek (siman 92).] Brachot 36b implies that it is permitted to buy food from a non-Jew that was cooked in a pot that wasn’t used within 24 hours. That is evident from Rashi s.v. sharya. That is the accepted opinion of many rishonim and poskim but the Meiri in Magen Avot understands the Rambam otherwise. See Yabia Omer 7:7:2.

* Isur Vheter 47:9 writes that it is initially forbidden to buy from a non-Jew an animal that nursed from a non-kosher animal but after the fact it is permitted. Torat Chatat 65:10 cites this. Shach YD 60:5 writes that the reason it is permitted after the fact is zeh vzeh gorem. The Erech Hashulchan 99:8 infers from here that it is forbidden to buy a food that the non-Jew did a nullification in its processing in line with the Radvaz 3:547.  

* Rambam Maachalot Asurot 3:13 and 3:15 writes that the cheese of non-Jews is forbidden since they might have used rennet from a nevelah animal which isn’t nullified. Erech Hashulchan infers that had it been nullified it would have been permitted to buy unlike the Radvaz.

* Hagahot Shaarei Dura 1:1:7 asks how it is permitted to buy spices from non-Jews initially since it involves nullification. He suggests that perhaps it is permitted since it was done by a non-Jew.</ref>

# If the taste of a forbidden food negatively impacts a mixture that it fell into the mixture is permitted.<ref>Shulchan Aruch YD 103:1. The two major approaches as to why it is permitted is that of the Ran and that of the Rashba. Ran Avoda Zara 67a explains that one may not benefit from  something non-kosher and so if it is intact it is forbidden unless it isn't fit for human consumption. However, if its taste is absorbed in a mixture it is permitted as long as it imparts a negative taste since one isn't benefiting from the non-kosher addition. The Rashba Torat Habayit Haaruch 19a argues that the item itself is permitted only if it is inedible and loses its status of a food. But if it is mixed into a mixture it is permitted since there is a nullification of the substance of the food with a simple majority and the taste of the non-kosher doesn't make the mixture forbidden as long as the taste is negative. The concept that a taste is forbidden even if it is nullified by a majority doesn't apply to negative tastes.  

* Rabbi Akiva Eiger (Chidushim Chullin 97b n. 7) applies the idea of Rashba requiring a majority even to the absorptions in pots. The Bet Yehoshua 102:6 argues that it only applies to absorptions in foods or foods that were dissolved but not absorptions in pots. Based on his understanding he answers the question of Rabbi Akiva Eiger 1:27 on Shach 102:8.</ref>

# For example, bugs that fell into a food and were removed the food is permitted since the taste imparted by the bugs is negative.<ref>The Maharshal (Yam Shel Shlomo 7:48) learns from the Rambam (Maachalot Asurot 15:31) that a mouse in any liquid besides wine, honey, or oil which need to smell nice to be edible are forbidden. There isn't a leniency of noten taam lifgam for a mouse falling into any liquid. Similarly, in 7;49 he is strict about bugs falling into any liquid since we're not sure whether it imparts a negative taste. He admits that the Ran learns that the taste of a mouse is always negative besides for beer and vinegar and the Rashba (Torat Habayit Hakatzar 16b) holds that tastes of bugs are negative for all foods, he disagrees. Taz cites this Maharshal who disputes the Shulchan Aruch 104:3 codifying the Rashba.</ref>

# Meat in oil is considered by some to be contributing a negative taste and if the meat is forbidden and its taste gets mixed into the oil it is permitted, while others disagree.<ref>The Rambam and Shulchan Aruch 103:4 hold that meat in oil imparts a negative taste and if its taste gets into the oil it is permitted. Shach 102:14 quotes Tosfot avoda zara 38b and many other rishonim who disagree. Shach concludes that we need to be strict. See Badei Hashulchan Biurim on 102:4 who asks why we can't discern what is considered noten tama lifgam based on our tastes.</ref>

# Meat in honey according to many poskim is considered to impart a positive taste.<ref>The Rambam and Shulchan Aruch 102:4 write that meat in honey imparts a negative taste. Bet Yosef qualifies the Rambam to plain meat but not spiced meat. Rama 102:4 writes that it only imparts a negative taste into mead but not real honey. Shach 103:14 quotes others who agree with the Rama.</ref>

# A forbidden food which spoiled and became inedible is Biblically permitted but rabbinically forbidden.<ref>The [http://www.hebrewbooks.org/pdfpager.aspx?req=44929&st=&pgnum=144 Minchat Cohen Tarovet 1:9] writes that the Rambam Machalot Asurot 14:11 implies that eating forbidden food which is inedible is Biblically permitted but forbidden rabbinically. He says further that it is even rabbinically permitted if it is mixed into a mixture even if there is a majority of forbidden ingredients as is evident from Shulchan Aruch 103:1. Pri Megadim M"Z 103:1 cites this.</ref>

# If a forbidden pot was used after 24 hours to cook kosher food the food remains kosher.<ref>Shulchan Aruch 103:5</ref> One may not use a forbidden pot intentionally but if one did so according to many poskim the food is nonetheless permitted.<ref>Rashba Torat Habayit Haaruch 4:4 38b writes that it is forbidden to ask a non-Jew to cook in his teref pot that wasn’t used within 24 hours since it is considered bitul isur lechatchila. Rashba writes that it is forbidden even after the fact. Shulchan Aruch YD 103:5 and 122:6 quotes the Rashba but not the part that it makes it forbidden after the fact. Even though the Levushei Sarad and Chamudei Doniel say it is forbidden even after the fact like the Rashba, Igrot Moshe YD 2:41 argues that after the fact were lenient.

* Rashba Torat Habayit Haaruch 38a, Meiri in Magen Avot 13 p. 58, Bet Yosef 122:6, Raah 38a, Meiri A"Z 76a, Radvaz 3:617, Sedah Lderech 2:3:7, Mordechai a"z ch. 2, Tosfot Rid a"z 75b, Erech Hashulchan Sefer Hazikaron 50:8, Yabia Omer YD 8:14, Knesset Hagedola 122:26, Pri Megadim S"D 99:7, Bet Shlomo YD 175, Adovat Avoda Avoda Zara 75b, Mor Ukesiah, Zivchei Tzedek 122:15, and Maharil Diskin Kuntres Acharon 129 hold that if the food was cooked in an eino ben yomo pot intentionally the food is forbidden. However, the Tiferet Lmoshe 94:22, Arugot Habosem YD 99:3, and Zayit Raanan Dvar Sheyesh Lo Matirin 3:2 are lenient.</ref>

# An earthenware vessel that absorbed something non-kosher can't be used even after 24 hours.<ref>Pri Megadim Siftei Daat 103:17 writes that even for earthenware vessels they can't be used after 24 hours even though there's no way to kosher them. He is disagreeing with the Nachalat Yakov 23-25, 42. Badei Hashulchan 103:54 agrees with the Pri Megadim.</ref>

# If a person used an eino ben yomo meat pot for dairy the food is permitted and the pot needs to be kashered<ref>Shulchan Aruch Y.D. 93:1</ref> but it can be koshered with hagalah even if it was used on the fire. The same is true of a dairy pot for meat.<ref>Chatom Sofer YD 110 writes that if an eino ben yomo meat pot is used for dairy on a fire it would still only be hetera baala since both the meat and milk entered the pot separately bhetera since the meat was eino ben yomo when the milk went in. He adds as a chumra to do hagalah three times. Pitchei Teshuva 121:7 cites the Chatom Sofer. Siach Yakov (Machalei Akum Hechsher Kelim p. 218, Rav Yakov Kassin) agrees. Shulchan Aruch Y.D. 121:4 writes that whenever it is hetera baala even a roasting pot only requires hagalah.</ref>

# Food cooked in a pot that wasn't used within 24 hours even if the pot wasn't kosher the food is kosher after the fact.<ref>Shulchan Aruch YD 103:5</ref>

# If someone doesn't know if a pot was used within 24 hours after the fact the food is permitted since it is possible to assume that it wasn't used within 24 hours.<ref>Tosfot Avoda Zara 38b and Ramban Avoda Zara 35 hold that stam kelim einam bnei yoman, we assume that most pots weren't used within 24 hours. Tosfot and Ramban explain that it is based on a safek safeka. There is a safek if it was used within 24 hours and even if it was it could be that the absorption in the pot won't give any taste to the food or that the taste it'll give will be a negative contribution to the taste of the food. Rambam Machalot Asurot 17:22 seems to disagree with this concept and hold that stam kelim are bnei yoman. Kesef Mishna makes this point. Rabbi Akiva Eiger YD 122 notes that this also seems to be the opinion of Rashi Yoma 81b s.v. sharya. Mahari Ibn Chaviv in Tosefet Yom Hakippurim Yoma 81b also makes this point. (Yabia Omer YD 7:7 cites these opinions.) According to this note, it seems that the same can be proven from the Bahag Brachot 36b and Meiri Brachot 36b. However, with respect to that same Gemara source the Smag Mitzvah 27 writes that stam kelim are assumed to be not bnei yoman. Talmidei Rabbenu Yonah Brachot 25b s.v. umirkachat agrees. The Shulchan Aruch YD 122:6 agrees with the Tosfot, Ramban, Smag and Rabbenu Yonah that stam kelim einan bnei yonam.</ref>

# Some say that it isn't necessary even to inquire if the pots were used within 24 hours if it would embarrassing to ask.<ref>Yabia Omer 5:3:2 citing the Dvar Shmuel 320, Radvaz 4:296, Pri Chadash 110, Masa Melech 7:10 that it isn't necessary to ask to find out more information about a safek safeka unlike the Shach 110 Klal 35. Nonetheless, maybe everyone would agree here since it is embarrassing and maybe the owner wouldn't even know the answer.</ref>