When first learning about how fruit can become freeze dried, it surprised us to learn how old of a technique it actually is. Freeze dried fruit might be all the rage right now, but the process dates back a few decades.
The modern industry of freeze dried food really started in the late 1970s, when economic conditions led many to stockpiling and storing food for years at a time.
Another thing that surprised us is just how much time and energy it takes. Freeze-drying is one of the most energy-intensive ways to preserve food.
To give you an example of the energy involved, Mountain House, a leading supplier of freeze dried meals, freeze-dries its food in 3,000 pound batches for around 18 to 20 hours. The freeze dried product ends up weighing about 900 pounds and requires about 2.4 million BTUs of heat energy. That’s more energy than either canning or freezing food.
When talking specifically about how is fruit freeze dried, one of the reasons why it’s worth so much time and energy is because it’s one of the best ways to preserve fruit with minimal loss of nutrients.
The Freeze Drying Process
The process of freeze drying fruit takes place in three steps that, appropriately enough, begins with freezing the fruit.
The process begins with selecting top-quality fresh fruit, sourced from certified, carefully-selected growers who undergo a stringent audit review process. The fruit that passes our review process is then frozen to below 0°F.
In the next step, the fruit is placed in a vacuum chamber under low heat. In the vacuum chamber, a process called “sublimation” occurs when frozen water crystals evaporate directly from ice to water vapor. The fruit then undergoes one more session of drying under slightly higher temperatures to remove any remaining water molecules.
During the final step, the freeze dried fruit slices are collected and inspected. Qualified fruit slices are packaged into moisture-proof and air-proof packages to preserve nutrition, flavor, and freshness. At Crispy Green, the freeze dried fruit are packaged in high quality triple-layer poly-bags with an aluminum lining to protect the finished products from moisture and light for a long shelf life.
All Crispy Green fruit is processed and freeze dried according to the Hazard Analysis and Critical Control Point (HACCP) system, an international standard that identifies critical control points, sets safety procedures and preventive measures, and maintains strict documentation for certification.
Now that you know the process for how is fruit freeze dried, we hope you have an even greater appreciation for the work that goes into the delicious pieces of freeze-dried fruit you enjoy.
For more information about the freeze-drying process, please view our whiteboard video below!