Clarification (Part 1): It does not need to have actually turned sour, as long as it stands to turn sour, as the Gemara will say shortly.

Clarification (Part 3): Rebbi Yehudah considers it Vaday wine, since it can be purchased with Ma'aser-Sheini money ...

Clarification (Part 4): .. and even if it contains three Lugin of water apart from the wine, it does still not invalidate the Mikvah; because, just as it is considered a fruit with regard to purchasing it with Ma'aser-Sheini money, so too is it a fruit with regard to not invalidating the Mikvah.

Refuted Suggestion: We cannot attribute the concession to purchase it with Ma'aser Sheini money by giving it the same Din as the jar containing the wine, which one may purchase together with the wine ...

Refutation: ... because the two are simply not comparable, since, whereas the jar serves to safeguard the wine, this cannot be said about the water in the Temed, which can only be purchased because, due to the fact that it tastes like diluted wine, it is considered wine.

Implied Question: And even according to the version that reads 'Chaser Kurtuv' in the Reisha of the Mishnah that the Gemara will cite shortly, implying that three complete Lugin would invalidate the Mikvah ...

Answer (Part 1): ... they are different, because whereas there it doess not taste like wine, but only looks like it, and we do not go after looks since it does not taste like wine too ...

Answer (Part 2): ... here, where it tastes like wine, it falls under the category of diluted wine ...

Answer (Part 3): ... and there where the wine has not turned sour, Rebbi Yehudah considers it like Vaday water, seeing as it invalidates the Mikvah, since Safek Mayim She'uvin is Kasher for a Mikvah.

Implied Question: And the reason that the Gemara does not establish the Machlokes where the wine did not turn sour, and our Mishnah goes like the Rabbanan is ...

Answer: ... because even Rebbi Yehudah will concede that there where it did not turn sour, one is Patur from Ma'asros.

Clarification: The Gemara is not querying the Din of 'Ein Nikchin be'Kesef Ma'aser', since the ruling forbidding purchasing a Safek with Ma'aser money is perfectly justified.

Reason: It is querying the Din of 'Posel es ha'Mikvah', since one cannot invalidate a Mikvah on the basis of a Safek ...

Source: ... as we learned in the Tosefta 'A Mikvah that one left empty and subsequently discovered full is Kasher, because it is 'Safek Mayim She'uvin', And this is also evident in many Mishnayos.

Clarification (Part 1): Rava is coming to teach us that even if a small amount of wine that is placed in a glass turned sour, it is considered water to invalidate the Mikvah as long as the bulk has not turned sour ...

Clarification (Part 2): ... like Rebbi Yochanan ben Nuri, who rules that three Lugin of water minus a Kortov into which a Kortov of milk fell is considered water to invalidate a Mikvah, since it resembles water in both taste and appearance, which is also the case here.

Query: Even though the two cases are not exactly the same, seeing as the water there is not going to taste like milk, nor can it be purchased with Ma'aser money; whereas here a. the juice stands to taste like wine when it turns sour, and b. the water itself will be considered wine inasmuch a it will be eligible to be purchased with Ma'aser money, as the Gemara explains in Eruvin (27b) - "ba'Sheichar", 'to include Temed from the time it turns sour.

Answer: Nevertheless, Rava maintains that, seeing as even actual milk is considered like water to complete the Shi'ur of three Lugin to invalidate the Mikvah, here too, it will invalidate the Mikvah, despite the fact that it stands to become sour, since now it both tastes and looks like water.

Clarification (Part 1): Even though Rebbi Yochanan ben Nuri mentions only the appearance ....

Clarification (Part 2): ... he nevertheless requires that it tastes like wine too.

Proof: The reason that Rava adds 'taste' is because it is obvious that white wine that looks like water will not invalidate a Mikvah, even it is mixed with three Lugin of water.

Question: Then why does Rebbi Yochanan ben Nuri not mention taste?

Answer #1 (Part 1): According to the text at the beginning of Makos (3b) that reads 'Chaser Kortov', implying that three full Lugin will invalidate the Mikvah, even though it looks like wine, in which case Rebbi Yochanan ben Nuri argues in the Reisha too and says that it will not, since it has the appearance of wine, even though it tastes like water ...

Answer #1 (Part 2): Hence he only mentions the appearance ...

Answer #2 (Part 1): ... whereas according to the text there that omits 'Chaser Kortov', and Rebbi Yochanan ben Nuri only argues in the Seifa ...

Answer #2 (Part 2): ... he nevertheless mentions specifically appearance, to teach us that both in the Reisha and in the Seifa, he goes after the appearance; and what he is saying to the Chachamim is 'Just as you concede in the Reisha that we go after the appearance, won't you concede in the Seifa that we go after the taste as well as the appearance?'

Question (Part 1): Why must we say that he argues with Rav Nachman? Why can he not hold like him ...

Question (Part 2): Perhaps he holds that even though Rebbi Yehudah renders Chayav Ma'aser once it turns sour or if it stands to turn sour, he nevertheless concedes that one cannot separate on it from another barrel of Temed unless both have turned sour, in case one of them stands to turn sour, whilst the other one doesn't, in which case it will be 'min ha'Chayav al ha'Petur' or vice-versa)?

Answer (Part 1): The reason that the Gemara says that they (Rav Nachman and Rebbi Elazar) argue is due to the Lashon of Rebbi Elazar, which implies that both the Rabbanan and Rebbi Yehudah agree that one cannot separate Ma'aser to cover it unless it has turned sour, but that if it has, one can . ...

Answer (Part 2): ... whereas according to Rav Nachman, who establishes the Machlokes by Hichmitz, the Rabbanan maintain that he is Patur even if it has turned sour.

Question: Like whom does Rav Nachman, who considers it a P'ri, as long as it stands to turn sour, even though it has not yet done so, really hold? Not like Rebbi Yehudah and not like the Rabbanan?

Answer: He will explain 'ad she'Lo Hichmitz' here to mean that it is not going to turn sour, where one left some in a glass and it did not become sour, just as he explained our Mishnah earlier.

Clarification: Whereas Rava thought that if the water initially became Tamei by itself, then the Hashakah too, is only effective when it is by itself.

Question: Rebbi Eliezer from Metz asks why we need to say that the two mixed? Why will the Hashakah not be effective even if the P'ri is floating on top ...

Source: Like we find in Perek Ta'aroves (Zevachim 78b) where the Gemara rules that wet wine and milk are not Chotzetz, since water tends to pass through wine to the person's body, in which case he has been Yotzei the Mitzvah of Tevilah?

Answer: It would seem however, that there is no Kashya, since the two cases are simply not comparable. This is because whereas on the back of a person or of a vessel the water penetrates through the wine, it does not do so by way of Hashakah (where there is only liquid).

Implied Question: Why did the Gemara not rather cite the Mishnah in Ba Si'man (Nidah 52a)?

Answer: Because the Beraisa specifically mentions Rebbi Meir?

Clarification (Part 1): This means that, on the one hand, the flesh is white, whilst on the other, Rebbi Yehudah requires the hairs to turn their location in the flesh, black ... for which purpose two hairs will suffice ...

Source (Part 1): As the Gemara there explains ...

Clarification (Part 2): Not that the black really needs to exceed the white, but that when the two hairs are lying flat, they give the impression that the black exceeds the white ...

Clarification (Part 3): ... meaning that it looks as if there are a lot of hairs there.

Alternative Text: Rashi there erases 'al ha'Lavan from the text' (thereby circumventing the need for the above explanation).