Many of us like not only to eat but also to make various pies with berries. And here blueberries are one of the most popular and delicious fillings.
However, when cooking, it often happens that the berries, releasing their juice, stain the dough blue, making the cake less attractive.
To avoid this, roll the blueberries in flour before cooking. This will preserve their integrity, and the flour will help to retain the juice and prevent it from turning the dough blue.