"Comments according to B&B Chef Extraordinaire mizkathleen: I pick our blueberries each summer and freeze between 50-100 pounds worth. I don’t thaw the blueberries in this recipe; I use them frozen. (Store bought blueberries get mushy once they are thawed. Ugh.) Of course if you pick and freeze your own they stay firmer because they are dry when frozen and don’t have preservatives on them, but I still use them frozen, when baking, which may explain why I bake it a lot longer than 60 minutes. With frozen blueberries, 75 minutes is more like it...."