Dear Rabbi Simon
I was looking at the sugar content of the grape juice I used to say Havdalah and was wondering if there is a healthier alternative. I am reluctant to use wine as I drive after Shabbat. If I can say Havdalah on grape juice, why can’t I say it on grapes? Similar question for Kiddush and Seder night.
Thank you for your imaginative question.
Too much sugar: You can dilute your grape juice (or wine) with water if you like, eg one part, one part. Or more, if necessary. As a recommendation, Kedem Concord grape juice is not as high in sugar as some others.
Also, note that you only need to drink about 100cc (3.5 fl. oz.) to fulfil the mitzvah and recite the berachah acharonah (blessing after a beverage).
You can squeeze your own grapes as well, if you like, however the mitzvah requires a cup, not a cluster. Grapes have a different berachah as well: “fruit of the tree”, whereas wine or grape juice is “fruit of the vine”. The reason for this is that the grape is further elevated when transformed into juice, compared to its natural, unimproved state. The honour of the mitzvah requires the “fruit of the vine” (ie wine) rather than the fruit of the tree, which is the grape itself.
BTW, there are grounds to prefer wine over grape juice, specifically for Havdalah (if you can imbibe safely).
Rabbi Rashi Simon