Did you know that 99 percent of fresh blueberries picked in Maine are sold frozen? In fact, most are frozen within 24 hours of picking. That’s why if you’ve ever gotten fresh Maine blueberries and didn’t want to have them go to waste, you need to learn how to freeze them.
Also, just because you freeze them doesn’t mean that they lose their flavor, freshness or nutrition. In fact, many frozen fruits and vegetables, including wild blueberries, are more nutritious than their fresh counterparts. That’s why it’s so important to freeze them.
How to freeze fresh blueberries
If you simply toss your fresh Maine blueberries in the freezer, you are bound to have issues. Blueberries, like most fruits and veggies, are made up primarily of water. In fact, according to Heathline, blueberries are 84% water.
As water freezes, it expands, which bursts the cell walls, especially if they are already weak. When you thaw the blueberries, you end up with mush. Choosing the right blueberries and using the right technique, however, helps retain more of the original flavor and texture that you want.
What are the best blueberries to freeze?
The best blueberries to freeze are small, wild blueberries like you find in Maine. The Wild Blueberries Association of North America (WBANA) offers this tip:
“To make sure you’re getting true wild blueberries, you’ll want to visit the frozen fruit section of your local grocery store and double check that the package says ‘wild’ on it.”
WBANA
In fact, the WBANA says that during harvest season — July and August — more than 90% of the crop is flash frozen at the peak of ripeness so you can enjoy the taste of Maine summer all year long. One of the reasons that they freeze so many wild blueberries is they maintain their texture better than the larger blueberries you typically see in the grocery store.
Just like the Maine blueberry farmers, when freezing them, you want the freshest blueberries at the peak of summer ripeness. That way they are as firm as possible with no blemishes or signs of spoilage. The blueberry skin is thickest and most structurally sound at this point, which helps significantly when you thaw them later. In other words, they’re less likely to turn to mush.
“Freezing blueberries is so easy and it’s a great way to preserve the flavors of summer all season long,” says Renee Gardner who writes the blog Renee Nicole’s Kitchen. “I love frozen blueberries with a square or two of chocolate for a late night snack.”
Prepping blueberries to freeze them
Before you freeze the blueberries, be sure to wash them gently in cool water. Warm or hot water will damage the skin and make them more prone to becoming mushy. There are a couple of schools of thought on washing blueberries.
You do not need to use all the fancy fruit and vegetable washes and sprays you can buy. Just water cleans them adequately, but you can also use three parts water mixed with one part vinegar, mix a tablespoon of 3 percent hydrogen peroxide with a gallon of water, or combine a teaspoon of salt with a cup of water to clean your produce.
“I have three blueberry bushes, so I freeze a lot of berries,” says Jere’ Cassidy who writes the blog One Hot Oven. “Just wash them in baking soda mixed with vinegar to get the dirt off. This also inhibits bacteria.”
More tips on sorting, washing and storing blueberries in this article on how to make summer berries last.
How you dry blueberries before freezing them
Be sure to pat them dry before you freeze them. Any moisture on the outside of the blueberry turns to ice. That ice can contribute to the blueberries losing the texture you want to maintain.
How do you ensure that the blueberries are all the way dry before you freeze them? Simple. Place them on a double layer of paper towels, then gently use another paper towel to carefully roll them to dry them thoroughly.
Depending on how many blueberries you wash, you may need to change out your paper towels a couple of times. Be sure to be gentle during this step, as you do not want to damage the blueberries at all. And why paper towels? Because they are thinner and you’re less likely to smush the fruit as you might if they were under a heavier kitchen towel.
Alternatively, you can set them on a double layer of paper towels and let them rest for 10 to 20 minutes. After that time has expired, change out to new paper towels and ensure they dry completely.
The best way to freeze fresh blueberries
Place your clean blueberries on a jelly roll pan lined with parchment paper. The parchment paper helps to ensure the blueberries don’t freeze to the metal pan and get damaged. At the same time, the sides of the jelly roll pan ensure the berries don’t roll off when you move the sheet pan to and from the freezer.
Keep the blueberries in a single layer, and do not pack them in. You are better off freezing a second tray where the blueberries have space between them than trying to get them all onto one sheet.
Place your jelly roll pan in your freezer for two to three hours, until the blueberries are completely frozen. Once frozen, place them in a zip top plastic baggie with as much air removed as possible, then double bag them.
The double bagging helps keep them from getting freezer burn and also protects their texture for longer. If you have a vacuum sealer, this is a great time to use it.
Be sure to label your bag with the date you froze your blueberries. They will last in the freezer for up to six months.
How to use frozen blueberries
Frozen blueberries are great to add to any recipe that calls for blueberries or simply enjoy them by themselves.
When you bake recipes like blueberry dump cake, blueberry streusel coffeecake or sour cream blueberry muffins, be sure to add them to the batter while they are still frozen. While you might need to add a couple extra minutes to the cook time, they maintain their texture better when you don’t thaw them first and try to mix them into the batter.
For recipes like a blueberry crumble bar or blueberry syrup, it matters less if you thaw them before you add them to your recipe or not.
However, if you make a fruit salad or plan to use the blueberries to make pancakes or waffles — or anything with a short cook time — be sure to thaw them first.
How to thaw frozen blueberries
The way you thaw blueberries is as important as how you freeze them. Bottom line: you want them to maintain a good texture. While thawed blueberries will be softer no matter what, they don’t need to become mushy if you thaw them correctly.
The best way to thaw frozen blueberries is to place them in the fridge. Start by placing the blueberries you want to thaw into a container and cover it. Then, into the refrigerator to let them thaw for at least six to eight hours.
Why the slow thaw? This minimizes the damage to the cell walls that makes them mushy. If you plan to thaw your entire batch, you can move the bag containing them to the fridge and thaw them in that. Again, give them enough time to thaw slowly. With the whole bag, it could be longer than eight hours.
If you need them thawed more quickly, you can add them to a bowl of cold water, then change it with more cold water after five minutes or so. You may need to do this two to three times, depending on how many blueberries you want to thaw.
Do not use warm or hot water, as this will cause your blueberries to lose their texture. The same goes with thawing them in the microwave. Just don’t do it.
Buying frozen blueberries at the supermarket
The WBANA offers these tips if you’d rather buy blueberries frozen than freeze them yourself:
- Look for the words “wild blueberries” on the front of the package
- Check the list of ingredients on the back of the package for the word “wild”
- If all else fails, feel the berries in the bag; if they are small and pea-sized, chances are you’ve got the wild ones!
Not surprisingly, these Maine grocery stores sell frozen wild blueberries.
Final thoughts
By following these simple tips, you can ensure your frozen blueberries retain their firmness and taste as delicious as the day you first picked them. Whether you plan to bake with them or enjoy them as a snack, you’ll love the burst of flavor and freshness properly frozen fresh blueberries offer.
Portions of this article first appeared on Food Drink Life.