Decided to take a couple of tablespoons and add it to a half cup each of flour and water. At least that was the plan, but I grabbed the wrong scoop and now it's 1/3 of a cup each.  Whoops.

Jar 2

Much better results. Almost all the raisins were floating, indicating fermentation, there were easily visible bubbles on the surface, and a distinct wine-like smell. Exactly what I was given to expect.

I poured out 1 cup of liquid and discarded the raisins. The remainder was added to 1 cup each of flour and water, which has since had...interesting results. It mixed together fine at first, pretty liquidy but that's fine. By lunchtime (about 3 hours later) there was a layer of cloudy water that had separated out. Weird enough, but a few hours later the layer was in the middle of the jar, with a white flour layer above and below. Very clear layers, too. Weird.

Now, in the evening, there's a much thicker layer of liquid at the bottom, and a very thin layer of flour under it. Above, is a thickening layer of bubbly white stuff that's expanding to fill the jar.  I've set it in a bowl, fully expecting it to overflow during the night, even though I had quite a bit of headspace to start with.

As to the other 1 cup of raisin water, I decided what the hell, let's use it to make bread if possible. So I used the basic recipe from the Tassajara Bread Book, my go-to loaf. And...the sponge stage was disappointing. I left it to rise pretty much the whole day and it did change texture and get bubbly, but it didn't rise much at all and while the usual texture after an hour is kind of light and gelatinous, after about 8 or 9 hours, this was more molasses-ish. I was told by someone on Mastodon that I should really go through a couple of feedings before using it for cooking, but well, I'd gone this far.

So I went ahead with the recipe. It kneaded up...pretty much like you'd expect with bread to be honest. The sponge was a bit flatter than expected, but honestly it wasn't that bad once I added salt, oil and more flour. It took a bit more flour than expected since it was a bit sticky, but nothing at all ridiculo9us. It's sitting in the oven to rise, has been for about 3 hours now. I intend to punch it down in another hour and let it go overnight. If it's doubled by morning, I'll try baking with it.

The weird part for me honestly was the smell. With commercial yeast, I think the early stage of dough smells quite a lot like bananas. Maybe that's what the yeast strain comes from, I have no idea. But this stuff smelled wrong. And it took me a while before I realized that was because it smelled like wine, not bananas. And not very good wine either. Crappy wine that you'd need to be seriously desperate to drink.  But that's fine, once it's baked (assuming it rises), that should go away.

Here's hoping it doesn't kill me though.