Công Nghệ Sấy Đông Khô Chân Không: Từ Nguyên Lý Đến Ứng Dụng Quy Mô Lớn
Nguyên lý cốt lõi, thông số quy trình chính, economic analysis and scale-up of vacuum freeze-drying technology — with CVD series specifications.
Vacuum freeze-drying (lyophilization) is a sublimation-based dehydration process fundamentally different from hot-air drying.
Three Core Stages
| Stage | Temp Range | Pressure | Process |
|---|---|---|---|
| Pre-freezing | -30~-40°C | Ambient | Free water crystallizes |
| Primary (sublimation) | -20~-10°C | ≤100Pa | Ice→vapor, removes 95% water |
| Secondary (desorption) | 20~50°C | ≤50Pa | Bound water desorbed, ≤3% moisture |
Water transitions directly from solid to vapor, bypassing the liquid phase — preserving cell structure and nutrients.
Key Parameters
Freezing rate determines ice crystal size: slow (0.10.5°C/min) for meat/whole fruit; fast (15°C/min) for berries/vegetable slices.
Sublimation must stay below eutectic point. Above it, the porous structure collapses and rehydration drops 50%+.
Economics (CVD-1000, Strawberries)
| Item | Value |
|---|---|
| Batch input | 100kg fresh |
| Cycle | 20~24 hrs |
| Output | |
| Power |
CVD Series Specs
CVD-1000 (10m²), CVD-2000 (20m²), CVD-5000 (50m²), with Bitzer compressor, Leybold vacuum pump, LS controls.
Công ty Yuanxian Machinery | www.vacuum-fresh.com