Freeze-dried raspberries are raspberries that have had the moisture removed through intense cold rather than heat. Commercially freeze-dried raspberries are frozen, then vacuum-sealed to pull out all of the water. This preservation method is popular among proponents of green living because it requires no artificial preservatives and allows the berries to retain most of their nutrients.
Store-bought freeze-dried raspberries are normally hard, dry, and very crisp. They immediately regain a soft, chewy consistency when moistened with liquid. Cereal companies often include them in oatmeal blends and fruited breakfast cereals. The freeze-dried raspberries quickly absorb milk or water and add a fresh-fruit flavor to one’s morning meal.
Home cooks searching for a way to preserve raspberries for winter use have two options: purchasing a freeze-drying machine and dry freezing the fruit. Freeze-drying machines are usually expensive and impractical for gardeners and cooks that want to preserve just a few berries. A cheaper option involves dry freezing, which is done inside an ordinary freezer unit and is basically the same as freeze-drying. Temperatures inside a home freezer unit don’t typically fall as low as inside a freeze-dryer, so raspberries preserved in an ordinary freezer don’t usually dry out completely.
Dry freezing usually starts with gently spreading the raspberries out in the bottom of a freezer-safe container. One must then place the container inside a freezer unit for 24 to 48 hours. The longer the berries remain in the freezer, the more moisture evaporates out of them. The berries may then be placed inside a vacuum-sealable plastic bag and vacuum-sealed shut. This kind of freeze-dried raspberry must remain frozen or refrigerated until use.
Raspberries exposed to pesticides must be washed before being frozen. A very gentle pat-down with a paper towel is all they need to dry them after rinsing. Bruised or broken berry skins could result in freezer-burned supplies. If any of the skins break during washing, it is best to eat or use those berries immediately. Only whole berries freeze well.
Properly freeze-dried raspberries should remain fresh and edible for several years. Those stocking up on emergency food supplies should invest in freeze-dried fruits and vegetables. They may be difficult to find in local grocery stores, but online survivalist websites and organic food distributors generally sell freeze-dried raspberries, and other foods, at competitive prices. Uses for freeze-dried raspberries include: an ice cream garnish, an addition to a parfait, smoothie flavoring, or an ingredient in fruited trail mix.