Freeze-drying is a sophisticated dehydration technology that involves freezing wet materials or solutions at low temperatures, typically between -10℃ and -50℃ or lower. The process begins by cooling the product to form ice crystals, then reducing pressure to create a vacuum environment (1.3~13 Pa). Under these conditions, the ice sublimates directly from solid to vapor, removing moisture without passing through the liquid phase. This method effectively preserves the sample’s internal molecular structure, as the low temperatures slow down chemical reactions and molecular motion, preventing damage or degradation. Freeze-dried products—such as potato chips, berries, dates, mushrooms, vegetables, tofu, and more—retain their original flavor, texture, and nutritional properties, making this technology ideal for high-quality food preservation and processing.