The secret to baking with frozen blueberries
Don't be blue

Ah, a lovely batch of golden blueberry muffins.
Um, make that greenish-blue blueberry muffins.
Fresh blueberries are a pleasure to bake with.
But unless you have access to a blueberry patch, fresh berries can be quite expensive; and their season is short.
Enter frozen blueberries, the backbone of many a winter blueberry pie.
But pie is one thing. Muffins, scones, cake, and coffeecake are quite another, frozen berries bleeding juice into batter to turn these golden-hued beauties a sickly shade of purple-green.
This doesn't have to happen, you know. There's a simple solution.
Rinse your frozen blueberries before you use them.
Rinse berries in cold water several times – until the water is noticeably lighter when you drain them. It'll start out dark blue, but will gradually shade its way up to a watery red/blue.
When that happens, dry the berries well with several layers of paper towels, top and bottom.
Let's see what happens when we use them in muffins.
Gently and quickly stir the frozen berries into the batter. You'll see a few inevitable streaks of blue, but the entire batter shouldn't turn blue. If that starts to happen – stop stirring, you're done!
Clearly, it's easy to get golden muffins when you use fresh berries; they don't bleed at all (bottom left).
But this recipe called for 2 cups of fresh berries, plus an additional 1/2 cup of crushed fresh berries; let's see if crushing the berries (bottom right) turns the batter blue.
So far, so good. The muffins made with frozen berries are in back; with fresh berries in the middle, and with a portion of crushed berries in front.
Top to bottom: frozen berries, fresh berries, crushed berries. The frozen berries tinted the muffins just a bit...
...but not nearly as much as they would have had I not rinsed them.
This photo is from an earlier experiment; unrinsed frozen berries on the left; rinsed and dried frozen berries on the right.
Man, now I REALLY want a blueberry muffin, don't you? This berry-packed recipe is for Famous Department Store Blueberry Muffins, a clone of the sugar-crusted muffins once served in the top-floor café at Jordan Marsh, a Boston department store (and New England institution). Jordan's, sadly, is out of business; but their muffins live on.
Remember, rinse and dry those frozen berries before you use them; it DOES make a difference. Enjoy!
Note: To those of you below wondering about losing flavor and nutrients when you rinse the berries, it's true, you probably lose a little bit of the berries' nutrition. But most of the juice (and vitamins) remain inside the berries; and I doubt you could notice a difference in flavor. By all means, use berries without rinsing, if that's your preference. As usual – no baking police here!