1) THE TASTE OF "ISUR" PASSING THROUGH THE CONTENTS OF A POT
QUESTION: The Mishnah states that when a drop of milk falls onto a piece of meat, it prohibits the meat if the taste of milk is discernible in it. If the contents of the pot are then stirred (immediately after the milk fell in (RASHI DH Ni'er)), the drop of milk prohibits the entire contents of the pot only if there is enough milk to impart its taste to all of the contents of the pot.
The Gemara quotes Rav who says that since the milk imparts its taste to the piece of meat onto which it falls, the entire piece of meat becomes Asur like a Neveilah ("Chatichah Atzmah Na'ases Neveilah"), and in turn it prohibits all of the other piece in the pot, because they are the same "Min." Rav rules like Rebbi Yehudah who says that "Min b'Mino Lo Batel," and even the smallest amount of forbidden meat makes all of the permitted pieces become prohibited since they are all the same "Min."
RASHI's words (DH Amar Rav) imply that even if the pot was not stirred or covered, according to Rav the first piece of meat makes all of the other pieces become prohibited. (Rashi explains that according to Rav, even in the first part of the Mishnah -- where no mention of stirring has been made -- the forbidden piece of meat prohibits all of the other pieces.)
If the piece of meat onto which the milk falls is entirely outside of the gravy and does not touch the liquid at all (see TOSFOS DH Tipas, who writes that the entire piece is outside the liquid), how is it possible that it can make the other pieces prohibited? None of the milk (or Isur) absorbed in the piece that became forbidden can be transferred to the other pieces, since it is outside of the liquid!
One cannot answer that Rav agrees with the opinion mentioned later in the Gemara that says "Efshar l'Sochto Asur" -- an Isur that became absorbed in a piece that was later cooked with permitted pieces can be "squeezed out" from where it was absorbed and make the permitted pieces become prohibited (see Rashi DH u'Mai Kasavar), because even according to this opinion, the Gemara later (end of 108b) says that if the pot was not stirred or covered at all, the Isur that was absorbed into one piece cannot go out of that piece into others.
How, then, can the forbidden piece of meat make the other pieces of meat prohibited if there is no liquid to transfer the taste of Isur from the first piece of meat to the others? (See CHIDUSHEI HA'RASHBA.)
ANSWER: The RASHBA here cites TOSFOS (96b, DH Afilu) who refers to the Gemara in Pesachim (75b) that says that if a hot piece of Isur falls onto a hot piece of Heter, everyone agrees that the Heter becomes forbidden even when both are totally dry. Tosfos asks that according to the Gemara in Pesachim, why does the Gemara here say that only when the pot was stirred does the Isur spread out to forbid the Heter? Tosfos answers that when the piece is forbidden in its own right (for example, it is a piece of Tereifah), it can spread out even without liquid. In contrast, when the piece is forbidden only because of what became absorbed into it, the Isur cannot spread out unless the piece is resting in liquid (see Tosfos here, DH Tipas, and Insights to Chulin 100:3). Even though the whole piece is considered Asur like Neveilah, the piece cannot be stronger that the Isur itself, and since the absorbed Isur does not spread without liquid, the piece that it forbids cannot make the other pieces forbidden without liquid.
The RAN (43a of the pages of the Rif), however, disagrees with Tosfos and maintains that since the whole piece is considered like Neveilah, any taste that leaves the piece (not only the taste of the Isur) will make neighboring pieces forbidden. Everything that comes out of this piece (and not only the Isur that became absorbed in it) is now considered completely forbidden, as if this piece was an actual piece of Isur.
The LEV ARYEH explains that Rashi here follows the view of the Ran. Even if the piece on which the milk fell is entirely outside of the liquid, nevertheless since "Chatichah Na'asah Neveilah," the entire piece can make the other pieces forbidden even if it is dry. (D. BLOOM)
2) THE "CHIDUSH" OF THE PROHIBITION AGAINST EATING MEAT WITH MILK
OPINIONS: The Gemara says that the law that a mixture of meat with milk is forbidden is a "Chidush." Consequently, the law that the taste alone of a forbidden food can prohibit a permitted food cannot be derived from the prohibition of meat and milk.
What makes the prohibition of mixing meat with milk so unique?
(a) RASHI (DH Mai Taima) explains that the prohibition of meat mixed with milk is a Chidush because meat alone is permitted, and milk alone is permitted. Moreover, the prohibition is unique because not only may one not eat them together, but one may not even cook them together.
(b) TOSFOS (DH d'Chidush Hu) explains that the Chidush of the prohibition of meat and milk is that meat soaked in milk for a whole day is permitted mid'Oraisa, while cooking them together prohibits them.
RAV ELIMELECH KORNFELD shlit'a suggests that Rashi may be following his own opinion expressed elsewhere. Rashi earlier in Chulin (97b, DH Kavush) explains that the principle of "Kavush k'Mevushal" (foods that are preserved together are considered to have been cooked together) applies only when a permitted food is pickled (with vinegar or spices) together with a prohibited food. If the two were soaked together in water (or milk) without any pickling agent, then they are not considered to have been cooked together (see Insights to Pesachim 76:2). (This opinion is not the Halachah. The Halachah is that any foods that are soaked together for twenty-four hours are considered to have been cooked together.) According to Rashi, therefore, it is not a Chidush that meat does not become prohibited when it is soaked with milk all day.
3) THE SOURCE FOR THE LAW OF "NOSEN TA'AM"
QUESTION: According to Abaye, the Torah prohibits any mixture of a prohibited food with a permitted food when the taste of the prohibited food is discernible in the mixture. This law of "Nosen Ta'am" is derived from the prohibition of eating meat and milk together, which applies as long as the taste of the milk is present in the meat, even though the actual milk food is no longer present.
What is the source that a mixture of meat and milk is prohibited only when the taste of the milk is present in the meat? Perhaps a mixture of meat and milk is prohibition even when the taste of the other food cannot be discerned!
RASHI (DH Iy Chidush) explains that the law that a mixture of meat and milk is forbidden only when the taste of each item is present is derived from the law of the Zero'a Beshelah of a Nazir (Bamidbar 6:18). Even though the Zero'a -- which is Kodshim and may not be eaten by a non-Kohen -- is cooked with the rest of the animal, it does not prohibit the rest of the animal from being eaten by a non-Kohen, because the Zero'a is annulled by the rest of the animal which is sixty times the size of the Zero'a. Since the taste of the Zero'a is no longer discernible, the mixture may be eaten. Similarly, meat (that was mixed with milk) may be eaten when the taste of milk in it is no longer discernible.
Rashi's suggestion that the requirement of "Nosen Ta'am" of a mixture of meat and milk is derived from the law of Zero'a Beshelah is problematic.
(a) If we learn from the Zero'a Beshelah that meat is prohibited when it contains the taste of milk, then we should learn from the Zero'a Beshelah that the principle of "Nosen Ta'am" applies to all mixtures of forbidden and permitted foods. Why, then, does Abaye derive from the prohibition of meat and milk that all other mixtures are prohibited when the taste of the prohibited food is present? Why does he not learn this law directly from the Zero'a Beshelah?
(b) How can the Zero'a Beshelah be the source for the law of "Nosen Ta'am" for the prohibition of meat and milk, or for any other law? The Gemara earlier (98b) teaches that we cannot learn other laws from the Zero'a Beshelah, since it is a Chidush!
ANSWERS:
(a) Rashi does not mean that we learn from the law of Zero'a Beshelah that meat is prohibited when the taste of milk is present. Rather, the law of Zero'a Beshelah teaches the opposite: meat is permitted when the taste of milk is no longer present. We cannot learn from the law of Zero'a Beshelah that all foods that contain the taste of an Isur are prohibited, since Kodshim have unique laws with regard to taste (see 98b and 99a with regard to "Ta'am k'Ikar b'Kodshim"). We can learn from the law of Zero'a Beshelah only that when the mixture does not have the taste of the Isur, it is permitted. Therefore, the law that all types of mixtures with the taste of an Isur are prohibited cannot be derived from the law of Zero'a Beshelah, but rather it must be learned from the law of meat and milk (which does not involve Kodshim).
(b) The Gemara here is discussing the view of Abaye. It was Abaye who said that the law of Zero'a Beshelah is a Chidush, and he said this only according to the view of Rebbi Yehudah who maintains that "Min b'Mino Lo Batel." If the Halachah follows the view of the Chachamim that "Min b'Mino" is Batel, then we indeed may learn the Halachah of "Nosen Ta'am" from Zero'a Beshelah to meat and milk. (M. KORNFELD)

108b----------------------------------------108b

4) WHEN DOES MILK SPREAD TO OTHER PIECES OF MEAT IN THE POT
OPINIONS: The Beraisa discusses a case in which a drop of milk falls onto a piece of meat in a pot and imparts its taste to that piece. Rebbi Yehudah says that the piece of meat becomes Asur like Neveilah and prohibits all of the other pieces which are being cooked with it. The Chachamim say that the other pieces become prohibited only when the milk's taste is present in the sauce, thick gravy, and pieces of meat.
Rebbi states that he agrees with Rebbi Yehudah when the pot was not stirred or covered, and he agrees with the Chachamim when the pot was stirred or covered.
The Gemara says that "not stirred or covered" cannot mean that the pot was not stirred or covered at all, because in such a case the piece of meat (onto which the milk fell) would not impart its taste (of meat and milk) to the other pieces (and Rebbi Yehudah would not forbid them).
In what situation does the piece of meat not impart its taste to the other pieces when the pot was not stirred or covered?
(a) RASHI (DH Miflat) explains that when milk falls on the top of a piece of meat in a pot, it stays in that piece and does not spread to the other contents of the pot. Rashi's words imply that the taste of the milk does not spread even when the bottom of that piece was resting in the same gravy as the other pieces of meat. The milk does not reach the other pieces through the gravy, because it fell on the top half of this piece, above the level of the gravy.
(b) The RI cited by TOSFOS (96b, DH Im Yesh) disagrees with Rashi. According to Tosfos, the milk that falls onto the top of one piece of meat should travel through the piece of meat and into the gravy and other pieces in the pot (due to the heat of cooking), since they are all resting in the same gravy. Only when the milk falls onto a piece of meat that is not resting in the gravy at all does the milk not spread to the other pieces (for example, the milk falls onto a piece of meat that is resting on top of another piece).
This argument between the Ri and Rashi has practical ramifications in Halachah. For example, when milk falls on a piece of meat (that is touching the gravy) in a pot, it prohibits only that piece of meat and not the others, according to Rashi. The other pieces of meat remain permitted (even if the quantity of milk that fell on the first piece is more than one sixtieth of the contents of the entire pot), and one merely needs to remove the prohibited piece of meat.
According to the Ri, however, if the quantity of milk that fell on the piece of meat is significant (more than a sixtieth of the contents of the entire pot), then by falling on one piece of meat it prohibits the entire pot. In this situation, Rashi's view results in a lenient ruling, while the Ri's view results in a stringent ruling.
A second practical difference is how much meat must be in the pot in order for the milk to be Batel. When milk fell onto a piece of meat (that is touching the gravy) in a pot, is it Batel when there is sixty times more meat in the entire pot, or only when there is sixty times more meat in the piece onto which it fell? According to Rashi, there must be sixty times more meat in the piece onto which the milk fell in order for the milk to become Batel. If there is not sixty times more meat in that piece, then the entire piece of meat becomes Asur, and if the entire pot is then stirred it will prohibit the entire contents of the pot. In order for the contents of the pot to be permitted, the rest of the contents of the pot must be sixty times greater than the entire piece of meat that became Asur (and not just sixty times greater than the drop of milk).
According to the Ri, however, when milk falls on a piece of meat in a pot, it is Batel if there is sixty times more meat in the entire pot (as long as the piece of meat is touching the gravy).
In this situation, Rashi's view results in a stringent ruling, while the Ri's view results in a lenient ruling.
(For the Halachah in practice, see SHULCHAN ARUCH YD 92:2, SHACH #4, TAZ #14, and KAF HA'CHAYIM #5.)

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