Obviously, as someone who has
written repeatedly about beer, and has even provided
a review of a liquid substance claimed by its manufacturer to be beer, I am (obviously) not in the camp of the teetotalers. But as someone who does love fundamental Christian theology, I do from time to time come into contact with those who would strongly argue for the position of abstinence.
One recent case is that of David Brumbelow's
Ancient Wine and the Bible, where the author makes a number of claims to establish the idea that the faithful have always rejected ordinary wine with alcohol. One of the claims is that, instead of simply crushing the grape harvest and allowing it to ferment in vats or wineskins (Luke 5), the ancients were prone to taking large portions of their grape harvest and
boiling it down into a syrup that would keep through the year, then reconstituting it and making a drink from it.
Now there are all kinds of reasons to reject this, including the
Bible's silence on this practice (it's never mentioned), the lack of archeological evidence for this practice (large metal pots, etc..), the lack of fuel to do the boiling, the fact that boiling destroys Vitamin C and exposes the drinkers to scurvy, and finally (Luke 5 again) our Savior's notation that new wine would break old wine-skins, and that people preferred the old (drier, more fermented) wine. Really, any family that decided to do this would give it up when they got scurvy and couldn't bake their bread or keep warm in winter.
But that noted, I decided last night to give it a try to see how it would come out, so I bought a can of grape juice concentrate (the bottles were all Concord grapes, the wrong species of grape), reconstituted it, and boiled it down to slightly less than its original volume--about a fifth of the original. This is where the sugar concentration inhibits yeast growth, and a little bit lower concentration than you'd need to stop all molds and bacteria--which is why most people refrigerate their jellies, of course.
What did I find? You can do it, I guess, and it is a sort of syrup at 75F (but definitely not in the fridge!), though I'd maintain what grandmother would tell you; the pectin in the grapes is going to change the consistency somewhat. It took about an hour of vigorous boiling on the stove to eliminate about 40 ounces of water from the mix. If you had a large pot like the one Grandma used to make apple butter, you might boil off a few gallons per hour, but overall, you're talking dozens or hundreds of hours of time in front of a fire in July and August to do this--and you're going to burn a lot of wood. I estimated about 2kW-H for my experiment, which is about a kG of coal burned. So for a family's 1 ton grape crop, we're talking about half a cord (100 cubic feet) of wood or so--again, you're going to be working hard to get this much, especially in an arid land like Israel.
Another note; average temperature in Israel in August goes up to 95-100 degrees or more. How does it sound to stand in front of that vat all day to stir it? Keep in mind that you could also just put the juice in skins or vats to ferment, or simply dry the grapes on your roof for raisins.
When reconstituted with some difficulty, it resembles a slightly charred version of KoolAid far more than a 2007 from Gevrey-Chambertin, and it's certain that no wedding host would say it's the best they've ever tasted. Keep in mind here that the pan I used was an
All-Clad--suffice it to say that my heat distribution was better than that of the ancients, so if they did this, their syrup would be quite a bit more charred than mine.
Verdict: it is extremely unlikely that this would have been done on a large scale anywhere around the Mediterranean. It's not witnessed in Scripture or archeology, it uses too much wood, and it would be a lot of work for the purpose of getting scurvy and water-borne diseases instead of enjoying robust health by eating raisins and having a glass of wine.