“Dehydrated” is normally used to mean dried with heat and airflow, most often in a hot air tunnel or cabinet. “Freeze-dried” means dried by sublimation: the product is frozen and the ice is removed as vapour under vacuum without ever becoming liquid.
The difference in physics produces the difference in product.
- **Dehydrated** product loses its structure as liquid water migrates out and the cell walls collapse. It is dense, chewy, visibly shrunken and usually darker than the fresh fruit. It rehydrates slowly and incompletely.
- **Freeze-dried** product keeps its structure, because the ice leaves through the framework it froze in. It is light, porous, close to the original size, crisp rather than chewy, and it rehydrates quickly and closely.
Freeze-dried costs substantially more per kilogram because the cycle takes hours to more than a day, the energy load is high and the equipment is expensive per unit of throughput. It also requires high-barrier packaging, because the porous structure absorbs atmospheric moisture readily.
Neither is better in the abstract. Choose dehydrated for chewy snacking, bakery inclusions and cooked applications; choose freeze-dried for instant applications, visible toppings and anywhere the fruit has to look and taste close to fresh after water is added.