冻干猪主动脉过程中升华界面移动特性实验研究

STUDY ON THE CHARACTERISTIC OF SUBLIMATION INTERFACE'S MOVEMENT IN FREEZE-DRYING OF THE PIG'AORTA

利用微CT扫描技术对猪主动脉在冷冻干燥保存中升华过程进行观察,分析升华界面移动特性,并使用质构仪对猪主动脉冻干前后力学性能进行检测。结果表明:干燥过程中对物料底部进行加热,升华是在外表面和内表面同时进行的。升华界面随干燥时间推移不断向壁面中心靠近。升华刚开始物料干燥速率比较快,界面移动明显,随着干燥层增厚,传质阻力增大,升华速率减慢,界面移动变化较小。质构实验对力学性能检测结果显示血管经冷冻干燥后其弹性和耐压性等与新鲜猪主动脉相比基本得到保持。

Micro-CT scanning was used to observe the sublimation process in freeze-drying preservation of the aorta of pig. The characteristic of sublimation interface＇s movement were analyzed and mechanical properties of the artery were determined before and after freeze drying using texture analyzer. The results showed： when heated at the bottom of materials, sublimation occurred both in the outer and inner surface of materials at the same time. The sublimation interface slowly approach to the middle of vessel wall change with time. The sublimation rate was high and the movement of the interface was obvious at first. Along with the dried area becoming thicker, resistance for mass transfer increased, sublimation rate became lower and the movement of interface turned not very clear. Mechanical properties test showed the elastic and anti-pressure of artery was kept basically after freeze-drying Compared with the fresh one.