1) WHAT IS A "REVUCHAH"?
OPINIONS: The Mishnah discusses the three types of Matzos that are brought in a Korban Minchah: Chalos, Rekikin, and Revuchah. (See the definition of Chalos and Rekikin, and the defining differences between them, in Insights to Menachos 74:2.) What is the definition of "Revuchah"?
(a) RASHI KESAV YAD (DH u'Revuchah) explains that these are unleavened loaves made of boiled flour. Although Rashi does not say what the flour is boiled in, presumably it is boiled in water. This is stated explicitly by Rashi earlier (53a, DH Revuchah).
(b) However, Rashi later (78a, DH Mena Hani Mili) says that Revuchin are boiled in oil. The TAHARAS HA'KODESH points out this discrepancy in Rashi's words. The EIZEHU MEKOMAN says that this question is not problematic, because it is not Rashi in Kesav Yad who says that Revuchin are boiled in oil, and thus it may be a different opinion.
(c) The TIFERES YISRAEL quotes a different opinion in the name of the Mechilta. He states that the flour is kneaded with boiling oil and then baked.
(d) There are two different texts of RABEINU GERSHOM on the Mishnah. One text states that the Revuchah is boiled in "Roschin," which implies boiling water, and the other text states that it is boiled in oil. Whether it is boiled in water or in oil, Rabeinu Gershom earlier (50b) has a unique opinion with regard to at least some of the types of Revuchah. He states that the Chavitei Kohen Gadol are boiled after they are baked.
(e) The RAMBAM (in Perush ha'Mishnayos 9:3) initially seems to agree with Rashi. He writes that the main feature of a Revuchah is that it has a lot of oil. He explains that the Revuchah is fried in boiling oil, and the flour of the Revuchah is "floating in oil" when it is fried. The Gemara (89a) explicitly says that the Torah states the word "Shemen" an extra time with regard to the Revuchah. This extra word must be teaching that the Revuchah is brought with more oil than the other types of Matzos. (The first opinion, that of Rashi in Kesav Yad, obviously agrees to this as well, since this is an explicit Gemara. He apparently understands that the oil is first mixed with the flour, and only then the flour is boiled in water.)
However, the Rambam elsewhere (Hilchos Ma'aseh ha'Korbanos 9:19) writes that the definition of a Revuchah is that "he boils it in Roschin (boiling liquid), bakes it a little bit, and afterwards deep-fries it with oil in a frying pan and similar utensils, like the way Sufganin are deep-fried, and one increases the [amount of] oil, and this is the Revuchah that is mentioned in every place." It seems that the Rambam maintains that both processes, boiling in water and deep-frying in oil, are performed.
The Rambam discusses, in two different places, how the procedure of boiling (Choltin) is done with flour. In Perush ha'Mishnayos to Pesachim (2:7), the Rambam says that Choltin is when "the flour is kneaded with strongly boiling water." In Perush ha'Mishnayos to Chalah (1:6), the Rambam calls this process "Me'isah," and says that Chalitah is when "boiling water is poured onto flour." (Y. MONTROSE)

77b----------------------------------------77b

2) THE AMOUNT SEPARATED AS "CHALAH"
QUESTION: The Gemara derives from the laws of Terumas Ma'aser that when one separates Terumas Lachmei Todah, he must separate one out of every ten loaves. The Gemara asks why the amount of Terumas Lachmei Todah is not derived from the laws of Terumas Chalah. What is this amount?
RASHI (DH v'Leilaf mi'Terumas Chalah) says that the amount is one out of forty-eight (1/48). Rashi in Kesav Yad (DH Terumas Chalah) says that the amount is one out of twenty-four (1/24).
Both of these amounts are mentioned in Maseches Chalah (2:7). The Mishnah there states that the amount that a homemaker must separate for Chalah is 1/24, while the amount that a baker must separate is 1/48.
However, the words of the Gemara seem problematic. The amount of Chalah (1/24 or 1/48) was instituted by the Rabanan. Mid'Oraisa, there is no minimum amount of Chalah (see Rashi to Bamidbar 15:20, RAMBAM in Hilchos Bikurim 5:1, and SHULCHAN ARUCH YD 322:1). What does the Gemara mean when it asks that the Torah law of how much Terumas Lachmei Todah must be separated should be derived from the amounts given for separating Chalah, amounts which are only mid'Rabanan?
ANSWERS:
(a) The NODA B'YEHUDAH (YD 2:201) answers that there are two separate elements to the Mitzvah of Chalah. One element is the separation of Chalah which remove the status of Tevel from the dough. Another element is the Torah's commandment to give the Chalah that is separated to a Kohen. The Noda b'Yehudah explains that when we say that mid'Oraisa there is no minimum amount of Chalah, we refer to the first element of the Mitzvah. This means that once any amount of Chalah is separated, the dough is no longer Tevel. However, with regard to the requirement to give one's Chalah to a Kohen, mid'Oraisa one must give either 1/24 or 1/48 of the dough. This is because the verse says, "You shall give to Hash-m a Terumah" (Bamidbar 15:20). The requirement to "give" obligates that the giving be of a minimum amount, a "Kedei Nesinah" (an amount which is worthy to give).
One of the proofs he cites for his novel explanation is the comment of Rashi (Bamidbar 15:20-21), who says that the Torah does not specify any minimum amount for Chalah. However, on the very next verse, Rashi comments, "Since we have not been taught an amount for Chalah, the Torah says 'Titnu' -- 'you shall give,' teaching that there should be an amount worthy to give (Kedei Nesinah)." This comment seems to contradict the previous comment of Rashi, in which Rashi says that no minimum amount is required by the Torah!
The RE'EM answers that Rashi is merely quoting an Asmachta from the Sifri. That is, the minimum amount is mid'Rabanan and is not derived directly from the verse.
The Noda b'Yehudah, however, proves that his explanation is the intention of Rashi. Rashi first discusses only the amount of Chalah that one must separate in order to remove the status of Tevel from the dough. In his second comment, Rashi discusses the amount which must be given to the Kohen, which is mid'Oraisa.
The MITZPEH EISAN notes that the approach of the Noda b'Yehudah is actually expressed by the TOSFOS RID in Kidushin (58a). The Tosfos Rid asks why Terumah -- which also has no minimum amount mid'Oraisa but has a minimum amount instituted by the Rabanan -- does not have to be at least Kedei Nesinah when given to the Kohen. Whenever the Torah says that something must be given (such as Reishis ha'Gez; see Chulin 135a), the Torah requires that an amount of Kedei Nesinah be given! The Tosfos Rid answers that to remove the status of Tevel, separating any amount of Terumah suffices. However, to fulfill the Mitzvah to give the Terumah to the Kohen, one indeed needs to give Kedei Nesinah.
(b) The Mitzpeh Eisan himself answers that the question is not really a question at all. The Gemara is simply saying that Terumas Lachmei Todah should have the same laws as Terumas Chalah. This includes both the Halachah d'Oraisa of Chalah (that the smallest amount exempts the entire batch) and the Halachah d'Rabanan (that one should have to separate either 1/24 or 1/48 to fulfill his obligation mid'Rabanan). (Y. MONTROSE)

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