Fast forward to now and I always use weights in my ferments. Generally it is these ceramic fermentation weights, but I’ll also throw a cabbage leaf or root vegetable slice in there if need be. Just anything to keep the veggies down. This batch had those weights until we started chowing down on it and then someone removed them. And it sort of just sat out at room temperature for several weeks before I opened it up again and found the discoloration. So, maybe no brine covering the top of the vegetables = leucoanthocyanidin = discoloration? That’s just my guess. I also think that adding more brine if your vegetables aren’t well covered by a couple of inches of brine or are not in an especially cool location helps.