Experimental study on Vacuum freeze-drying of Spirulina Platensis

In order to study impact of freeze-dring process on spirulina morphosis, influence of freeze-drying protecting agents and process parameters on morphosis of spirulina platensis and drying time were researched by orthogonal experimental design. Results indicate that the main influencing factors of total time of freeze-drying spirulina platensis are thickness, cooling mode, controlled shelf temperature, protecting agent in regular sequence, the impact of thickness is the most distinct and drying time increases with thickness in non-linear. The freeze-dried Spirulina platensis cell-contraction is less and the morphosis integrity is better when it is protected by diluted culture solution, self-frozen by vacuum pumping, filling thickness is 5mm, shelf temperature is -5 degrees C, which is in favor of preserving activity of platensis platensis cells.