Is there a problem with crushed grapes?

Question

I'm making my own grape juice with grapes bought from the local supermarket. Every so often I encounter a grape that is partially crushed. Do these crushed grapes present a problem of yayin nesech?

Answer 1

No. The issar of yayin nesrch is touching wine not crushed grapes.

In Shulchun Aurach YD 123 seif 17 explains that after the squeezing the grapes you have what is called must, it's the mixture of grape skins, flesh, and juice. At this point it's still not considered wine. After you separate the juice from that mixture which is called המשכה -to draw away. From this point on if a non jew touches that liquid it will be yayin nesach.

Answer 2

The source for this is the Gemara Avodah Zarah from the bottom of 59a to the top of 59b. Rabbi Yeimar says that a Gentile can bring grapes to the winepress even though the grapes are squashed and the juice sprays off, Rabbi Kahana clarifies that he is talking about what is allowed after the fact.

Tosfos there (sv. Mahu) clarifies what the squashing in the Gemara means. The Ri explains that the Gemara is only referring to when wine/grape juice has actually become separated from the grapes: if the wine just drips, it is not yayin nesech. As a result, Piskei Tosfos 116 says "אין לעובד כוכבים להוליך ענבים לגת שהתחיל למשוך": a gentile worker does not carry grapes to the winepress that started to pour out wine. Rosh (4:8), says the same; "לזורקו בגת בעוטה שהתחיל היין לימשך".

The Rashba concurs because it was never the intention of the gentile to create wine by putting the grapes in a container before they went in the winepress to create wine. I think there seems to be a nafka minah resulting from these Rishonim as to why Gentiles bringing grapes can be allowed: Tosfos because the wine has not separated vs. Rashba because there was no intention to produce wine. Either way, your situation is clearly allowed.

We then come to the Beis Yosef (YD 125). He agrees with all that has been said above. The rest of the difficulties in the Ran and Beis Yosef are about putting the grapes into the winepress, not supplying the grapes like in your situation. (I'm struggling to read this Ran so if I've got it backwards please correct me!). Shulchan Aruch (YD 125:6) codifies that bringing grapes is only allowed retrospectively, but qualifies like Tosfos that this only refers to "אף על פי שיש בדרדורים יין שזב מהענבים", when wine is pouring out from the grapes and has become separated. This is much more wine coming out of the grapes than "every so often I encounter a grape that is partially crushed" as in your situation. This is made explicit in the Taz (sk.9, see Baer Hetev sk.8 for a summary), who brings the Rashba's explanation above.

So, according to all the Rishonim, as long as the intention is to provide grapes that will then be pressed, the grape juice has not become separated from the solid grapes in a large quantity, and the grapes are not put into the vat by the Gentile, these grapes are permitted both retrospectively and from the beginning.

The Maharal Zunz explains the reasoning of the Rashba and Tosfos. Avodah Berurah summarises some of what I have said above.