Ask the Rov: How much alcohol must wine have to be considered wine?
By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah
From the Gemara it’s clear that freshly squeezed grape juice is acceptable for kiddush and the daled kosos (four cups).1 Indeed, the Rebbe advised someone with health issues to squeeze grapes for his four cups, and the Frierdiker Rebbe and the Rebbe did the same when wine wasn’t available according to their kashrus standards. 2
Yet, commercially produced grape juice that is treated and no longer has the same potential to ferment is subject to debate. The consensus is that it is nonetheless acceptable, though alcoholic wine is preferable for those medically permitted (see issue 194).3 One of the special qualities Chazal say about wine is that it brings joy, and that is not accomplished with grape juice.
The daled kosos are meant to exhibit and achieve a feeling of freedom and nobility, and thus, alcoholic wine is preferred. (Likewise, the reviis of wine drunk on each day of yom tov and chol hamoed for added simcha must be of alcoholic wine.)
How much alcohol must it have to be considered wine?
There is reason to say that 3.5% alcohol is sufficient based on the following: Wine in Eretz Yisroel naturally ferments to a maximum of 14-15% alcohol.4 In Talmudic times, the common practice was to dilute wine with three parts water to every one part wine,5 and Rava recommends this blend for the daled kosos to celebrate freedom (cheirus).6 It follows that the alcohol content of their wines after dilution was 3.5–4%.7
If drinking wine will interfere with performing the seder (i.e., tired or nausea), one should use either low-alcohol wine, a combination of wine and grape juice (1/3), or plain grape juice, to ensure that they can carry out the complete seder according to halacha.
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From The Weekly Farbrengen by Merkaz Anash
As quoted above There is reason to say that 3.5% alcohol is sufficient based on the following: Wine in Eretz Yisroel naturally ferments to a maximum of 14-15% alcohol.4 In Talmudic times, the common practice was to dilute wine with three parts water to every one part wine,5 and Rava recommends this blend for the daled kosos to celebrate freedom (cheirus).6 It follows that the alcohol content of their wines after dilution was 3.5–4%.7 THIS AMOUNT PF %14 OF MAXIMUM IS ONLY NOWADAYS, HOWEVER IN THE TIMES OF THE GEMARA WINE WAS ON AVERAGE 28% WITH MAXIMUM OF OVER %60
from what I’ve seen, it’s impossible scientifically for wine to ferment to such high percentages, if there is a makor for this, aderaba
It’s mentioned more then once in שולחן ערוך that מזיגת הכוס was only necessary בזמן הגמרא because their wine was stronger