Raspberries have something that the rest of the berry world doesn’t: gush in your mouth sweet and slightly sour velvety goodness. As special as they are, they are equally fragile. They crush easily and don’t stay fresh very long.
If you want to be able to enjoy them over days, weeks or even months, you need to find a way to preserve them without compromising their innate perfection.
Freezing raspberries is a great solution if you’re careful about it, but if you want to maintain their integrity without sugar, you’ll have to do things a little bit different than your grandma might have taught you.
How To Wash Raspberries Before Freezing Them
The most important consideration is to start with raspberries that are ripe, but barely. You want them to still be firm enough that they won’t mush or squish when you wash them.
Cleaning them is important to get any debris or tiny insects off but tossing them under the pressure of a running tap will just pulverize them.
Instead, fill a large bowl or bucket with water and then carefully set your raspberries in a colander.
Dip the colander into the bowl letting the water run over the raspberries. Lift it in and out a few times to make sure the water rinses all your berries well.
Once you’re happy that they’ve been sufficiently cleansed, lay them out gently on a baking sheet lined either with a clean dish towel or paper towel. Let the berries dry thoroughly before trying to freeze them.
If there’s any water left on them when they hit the freezer, the water will turn to ice and compromise the quality of your berries.
How To Freeze Raspberries (Without Sugar)
Flash Freezing Raspberries
Commercially flash-frozen foods use cryogenic temperatures and circulating air to freeze items as quickly as possible, before they have a chance to develop any ice crystals between the fibers of the food.
While your home freezer likely doesn’t go to such low temperatures, you can still get the effect and benefits of flash freezing.
Once your raspberries are completely dry, you want to lay them out in a single layer with space in between each berry on a baking sheet lined with parchment paper.
It’s important you use parchment paper and not wax paper, aluminum foil or plastic wrap because you don’t want to take the chance of your raspberries freezing to the surface. Parchment is non-stick, hot or cold.
Put your baking sheet carefully into the freezer and let your berries freeze for about half an hour. At this point, they’ll each be individually frozen with all their sweet tartness locked inside for good.
You can now transfer them to a freezer-safe Ziploc bag for longer-term storage.
Since they were frozen individually, they won’t stick together or smash when you load them all in together. Fresh, frozen raspberries will last up to 6 months.
Freezing Over-Ripe Raspberries
If you’ve waited a bit too long and your raspberries are already soft, you can still freeze them without sugar. They’re going to be great for smoothies or cooking, but they aren’t likely to retain their lovely, berry shape.
This means you can be a bit less delicate with them since you’re not expecting perfect at the other end.
Freezing Raspberries For Cooking
If you don’t need each berry to be individualized you can wash them gently as described above, let them dry thoroughly and then skip the flash freezing step, putting the berries directly into a freezer safe Tupperware container or Ziploc bag.
It’s a good idea to measure them out before freezing so that you know how much is in each container.
For example, if your favorite recipe calls for 1 cup of raspberries, measure out 1 cup portions and freeze appropriately. Once frozen, your berries are all going to stick together, so you’ll have to thaw out the entire portion all at once.
Freezing Raspberry Puree
You can also freeze raspberry puree. Wash your berries but instead of waiting for every last bit of water to evaporate, you can put them all into a food processor and puree them. You can then put them into a freezer safe Tupperware container. Make sure there’s a bit of room on top for the blend to expand as it freezes.
You can also freeze the puree in an ice cube tray first, and then transfer the frozen cubes to a Ziploc bag. This is great way to portion out small amounts for smoothies or homemade syrups.
Freezing Raspberries (Using Sugar)
Many people use what is called a “sugar pack” to extend the life and quality of their fruit. By dusting the berries with sugar and then very carefully mixing them, the sugar will draw out the natural juice from the berry.
This coats each tasty morsel with a very slight layer of syrup, protecting the berry itself from exposure to the air.
Using a sugar pack might help the berries retain their texture a bit better, and they’ll come out of the freezer with a slightly brighter color.
More importantly, they’ll last longer in your freezer, so if you need to store your berries for longer than a few months, you might want to consider a sugar pack.
As a general rule, you would use ½ – ¾ cup of sugar for every quart of raspberries. If you’re trying to maintain the shape and integrity of your berries, you’ll have to mix very carefully so as not to crush them in the process.
The sugar should be mostly dissolved before you pack them into freezer-safe containers.
This will create a block of berries, as opposed to individually frozen bite-sized pieces, so it’s a good idea to freeze in portion sizes that you’ll be happy thawing all at once.
Leave about an inch of space in the container to allow the berries to expand a bit when the freeze without oozing out into your freezer. Make sure the container is tightly sealed and don’t forget to label it with the date. Sugar packed berries will last for up to 1 year.
Thawing Frozen Raspberries
Berries thaw fairly quickly if they’re individually frozen but will take longer if you’ve pureed a batch or are thawing a solid chunk of berries. For best results, you can spread them out on a baking sheet covered with a paper towel to collect any residual moisture and let them warm to room temperature in your kitchen.
If you’ve got a solid chunk of berries or a container of puree, you can let it thaw in your fridge overnight. If you’re cooking with it you can simply add it to a saucepan and, over low heat and stirring often, thaw on the stovetop.
Using a microwave is not going to be the best way to thaw your berries as it won’t thaw evenly and some areas will cook while others are still frozen. If you’re going to nuke them regardless, make sure you work in 20-30 second bursts and stir often to try to disseminate the heat more evenly.
If you’re using berries in smoothie or shake, you can just toss them in your blender frozen. Individual berries are also delicious in cereals and they’ll thaw almost instantaneously in the milk.
How to know when raspberries are ready to be picked?
Raspberries need to be picked at just the right time to make sure they have maximum sweetness without getting mushy. Once they’re picked, they’ll stop ripening, so you don’t want to pick them too early.
Ripe berries will be bright and consistent in color, so there shouldn’t be any green or yellow bits left. If you pick one and the green stem comes with it, it’s not quite ready to be picked.
Pull a few off the bush from various spaces and give them a taste test. If they’re ripe, they should come off the bush easily and be firm, but not too hard. They should also be nice and juicy, bursting with flavor.
How do you preserve fresh raspberries?
First, you want to be sure they’re all fresh and none of them are squished or moldy in the slightest, as that is very contagious in your berries. You need to treat them very gently, storing them in a single layer if possible, and loosely covered.
They’ll last in your fridge for up to 3 days, but it’s a good idea to check them often to be sure they are all still in good condition. Wash them only when you’re ready to eat them, not before storing them.
Can you eat raspberries without washing them?
It’s never a good idea to eat fruit without washing it first as it could be harboring bacteria. Raspberries especially have plenty of nooks and crannies for bacteria to hide and grow. In all honesty, rinsing them is not likely to get off any pesticides used, so it’s good practice to splurge for organic berries.