They primarily dry fruit for cereal using a process called freeze-drying, which preserves the fruit's structure and flavor.
Here's a breakdown of the freeze-drying process:
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Freezing: The fruit is first frozen at very low temperatures (below freezing).
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Vacuum Chamber: The frozen fruit is then placed in a vacuum chamber.
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Sublimation: Inside the vacuum chamber, the pressure is significantly reduced. This causes the ice crystals within the fruit to transform directly into gas (water vapor) through a process called sublimation. Essentially, the water is removed without ever becoming liquid.
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Water Vapor Removal: The water vapor is then removed from the chamber, leaving behind the dried fruit.
Why Freeze Drying is Used:
- Preserves Structure: Freeze-drying helps maintain the fruit's original shape and texture because the water is removed as a gas, preventing shrinkage.
- Retains Flavor and Nutrients: Because the fruit isn't exposed to high temperatures, more of the natural flavor and nutritional value are preserved compared to other drying methods.
- Long Shelf Life: The very low moisture content significantly extends the shelf life of the fruit.
