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We picked the grapes in a local alley. They grow all over around here in St. Paul, fecund and forgotten. Unlike table grapes, these grapes (small, seedy, with a rather alarming flavor and texture to the unsuspecting) aren't really for eating raw. Best for making juice (or wine, cordial, etc, for those more knowledgeable than I) and jelly.
With a full pot of grapes, I added some water and turned the heat on. When all this rain dries up, I can't wait to try juicing in the solar oven! Anyway, on our regular gas stove, I simmered the grapes till the skins burst. The juice is dark, bright purple. An important step to note, that I often try to bypass, is letting this cool off a bit before moving on!
After boiling the grapes until they release their juice, I took a big mixing bowl, set it in the sink, and lined it with a clean dish towel. Into the towel I poured the grapes. Then I bound up the corners of the towel and tied it to the dish drainer, right above my bowl. When the dripping had slowed to almost nothing, I squeezed and mashed all the extra juice I could out into my bowl.
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As suggested by my guide, Mr. Thayer the forager, I let sediments settle to the bottom before decanting my lovely grape juice into a pretty pitcher. About two quarts of grapes made well over two quarts of grape juice. I mixed it with sparkling water, though I could have diluted it even more, it was so strong. Really it was grape juice concentrate! With just-ripening apples on my brain, I'm thinking that apple juice would make a superb sweetener for our next batch!
I hope to bottle a batch in those re-sealable German beer bottles, maybe also freeze a batch as concentrate, as part of our hoard of local goodness against the winter blues.
The juice was rich and delicious. Also made tasty popsicles!