What's your secret ingredient that makes your version of a common dish better than anyone else's?
Mine probably isn't that secret these days, but almost every sauce I add nutritional yeast to. Curry, chilli, bolognese, it just makes them all better.
For some reason that Concord Grape flavor is just overwhelming for me. Apple is a more neutral flavor. I started with apple because it was what I had on hand, but tried grape and went back to apple. It doesn't add the purple color, but as with wine, the fruit sugars caramelize to aid browning.
No, because you're heating it to oven temperatures, not just keeping it slightly warm. If it were cool enough to ferment the juice, the meat would be breeding botulism or e coli or something.