Kiddush on grape juice that's pasteurized or has added sulfites

Question

I'm working on a piece for a Sefer my Kollel is putting out on the topic of making Kiddush on grape juice that's pasteurized or has sulfites added (primarily based on שו"ת מנחת שלמה חלק א סימן ד, תשובות והנהגות כרך ד סימן סט, אשרי האיש פרק ז' אות נ"ט, and ברכת שמואל (להרב שמואל דרזי) עמ' רמ"ג)

The Teshuvos Vehanhagos (see also Rav Elyashiv) says that although you can use use pasteurized grape juice since if you add yeast to it it will ferment , you cannot use grape juice with potassium metabisulfite since if you add yeast to it it will not ferment (see there for his Raya that in order to be allowed to use grape juice it has to be on its way to fermenting).

One thing I've discovered (and the Birchas Shmuel touches on this as well) is that if you add wine yeast to even pasteurized grape juice with sulfites added it will have no problem fermenting. I've done it myself. Additionally there are many ways to get the sulfites (free SO2) out (either by letting them dissipate or making them bind with something else) which would then allow you to even use regular yeasts (although they can't get the alcohol content as high). However, I have not found a good source as to whether the fact that you are able to add something else to grape juice to make it ferment is enough to make it considered on its way to fermenting (as Rav Elyashiv and the Teshuvos Vehanhagos say is necessary) without adding anything. I haven't found anyone who disagrees with this explicitly although I have seen a few Poskim who clearly would hold its okay. Certainly the Minhag is to be lenient- after all most people in America would have no problem with someone making Kiddush on Kedem grape juice. Does anyone have a strong Raya as to whether the fact that you could add/do something to the grape juice to cause it to ferment is enough to make you allowed to make Kiddush on it without adding anything?

By the way, although I'm not done working on this piece I gave it as a Shiur yesterday, in part because I wanted to see what everyone attending the Shiur had to say. Anyway I only had about 20 minutes so I didn't get through anywhere near everything anyway. You will notice that I did mention that I had an open bounty on this question on judaism.stackexchange ;) I only remembered to say the story I found at @user15464's link after I ended the recording since it wasn't in my original Shiur plan so I restarted the recording afterwards (I also added a few more details I found after doing some more research). If you want to hear the story just don't get scared off by the way the recording goes silent for five seconds. You can listen to the Shiur here and if you have any comments please let me know as soon as possible so I can make changes before I publish in the coming weeks.

Update- The Sefer was published a while ago. If you'd like to see how I handled this you can download the Sefer here and read it on page 36. I go through all the Halacha and science there as well.

Answer 1

For the record, I did find a proof in the Har Tzvi (Orach Chaim 1:158):

ועוד הרי מבואר בס' חיי אדם (הל' שבת כלל ו סעיף ז) וז"ל: מצוה לקדש על יין או יין צמוקים ובלבד שיהיה בו טעם יין וכו', ומקדשין על יין מבושל, ולכן מותר לבשל הצמוקין ולסנן היין ולקדש עליו, עכ"ל. משמע להדיא דאף בצמוקין שנתבשלו מותר לקדש, מכש"כ בענבים שנסחטו ונתבשלו דראוים הם לקידוש. (יעוין רש"י מנחות דף פו ע"ב).

The Chayei Adam holds you can cook raisins and make Kiddush on the juice. That juice will not contain any live yeast but yet the Chayei Adam holds you can make Kiddush on it.

I'm still hoping for a significantly better proof, and I'm confident that a good proof from the Rishonim or earlier exists but I haven't found it (although I won't know for sure that I haven't found it until I'm done doing all the research @DoubleAA wants me to do).

The Shevet HaLevi 9:58 also brings some incredibly strong reasons why it should be permitted to make Kiddush even if it can't ferment, but as I mentioned in the question that's not what I'm looking for.

Answer 2

The source that Grapejuice must be alcoholic is from the Gemora Brochos35b:
The Gemora asks מאי שנא יין - why does wine have a unique Brocho different to grapes?
The Gemora answers אית ביה תרתי סעיד ומשמח - It has 2 properties its filling (when drinking in lesser consumption) and it Gladdens. The Gemora derives that wine is supposed to gladden from tehiim 104,15- ויין ישמח לבב אנוש.

Bava Basra 97b however says: סוחט אדם אשכול של ענבים ואומר עליו קידוש היום - One can the squeeze the grape juice from the grapes immediately prior to Kiddush (before Shabbos commences) it is considered wine even though it hasn't fermented yet. So we see its the potential that matters.

This is a quote from http://www.torahlab.org/doitright/using_grape_juice_for_kiddush/

The Gemara (Bava Basra 97b) states that one may (ipso facto) squeeze a cluster of grapes into their cup and say Kiddush, seemingly indicating that grape juice is permissible to use for kiddush, and all other sacramental purposes.
This is how the halacha is decided in Shulchan Aruch (272:2). However the Magen Avraham (3) adds that it is preferred to use aged wine, at least forty days old.
Rabbi Hurewitz’s position, and this position was initially held by Rav Henkin as well, was that our grape juice was different than the grape juice discussed in the Gemara. After squeezing grapes, the juice can either be turned to wine, or it will spoil. Contemporarily, in order to have grape juice, we pasteurize it, which gives it a long shelf life as unfermented juice.
The reason that grape juice was permissible in the Gemara was because it was, in essence, unfermented wine. However our grape juice, in order to preserve the grape juice it is necessary to pasteurize it, effectively neutering its potentiality of becoming wine. Thus, argued Rabbi Hurewitz, it was not the same as the grape juice of the Gemara.
Rav Tzvi Pesach Frank, (Har Tzvi, OC 1:158) in a letter to Rabbi Hurewitz disputes this. He writes that just as cooked wine is permissible for Kiddush, because we recognize it as retaining the character of wine despite it being cooked (and despite it not being usable in the Bais Hamikdash and therefore not being an ideal choice) so too grape juice will retain its character despite being cooked and will still be permitted. This is also the position of Rav Shlomo Zalman Auerbach (Minchas Shlomo 1:4).
Rav Henkin in a later responsum on the subject retracts his reservations regarding using grape juice for a different reason. He consulted with Mr. Herzog, of Herzog Winery fame, who demonstrated to him how one can easily fermented even pasteurized grape juice by adding a little sugar and yeast and leaving it exposed, thus refuting the pasteurization argument from a scientific perspective as well.

The common practice, and the position of the vast majority of contemporary poskim including Rav Moshe Feinstein, Rav Elyashiv, Rav Ovadia Yosef, Rav Soloveitchik, and the aforementioned poskim, is that grape juice may be used for Kiddush and all other sacramental purposes. Many do note the position of the Magen Avraham, that it is preferred to use wine when possible.

It seems that just like bread could leaven via sour dough which an external source and the Torah still prohibits this bread on Pesach as it has leavened despite from an external source, so too grape-juice can be externally fermented even after killing off the original yeast by adding new yeast. So the the pasteurized juice still has the potential to react with yeast which Bava Basra 97b says is considered wine, so that is why Rav Henkin consented after having seen that the grapejuice can still ferment with new added yeast.