I made something new today
I'm not sure if it's saba or mosto cotto. The difference seems to be possibly regional and definitely thickness - saba is supposed to be thicker than mosto.
Either way, it's essentially caramelized grape juice. It's Italian and it's a way to preserve grapes that aren't going to be used for other purposes (like wine). It's not unlike the various Middle Eastern syrups that are usually translated as 'molasses'. Pomegranate molasses is the one I see most often, but they also do grape and other fruits. It's a sweetener, used in place of sugar.
I had a chance at some cheap red and black grapes and decided to try it. Since I've never used or tasted it before, I knew it was a crapshoot and didn't have too many expectations. It was just for fun.
First problem came up right away - the store had prepackaged bags of fruit with a price per pound. I assumed each bag was a pound. Nope - try 2.5 pounds. I really overbought. And it wasn't as cheap as I planned. (I bought what I thought was 5 pounds.)
So, I made a batch using about half what I bought, which was still more than the 5 pounds the recipe called for. Good news - it's really good stuff. Like I said, caramelized grape juice. On the other hand, I got about half the amount the recipe promised. I suspect that when the recipe was translated, somebody read pounds instead of kilos. And I only cooked it down to maple syrup consistency; I stopped when it got thick enough to foam up to near the top of a very large pot.
So, it looks like I did get the right amount of grapes, if I want the amount of syrup I expected. I'll have to cook the rest tomorrow and can it for storage. But now I have to figure out what to do with it.