紫薯提取液超滤膜分离特性研究:过滤方式的影响

Investigation of Ultrafiltration Performance for Purples Sweet Potato Extract:Effect of Filtration Model

以截留分子量为100，50，10kDa的超滤膜为分离介质、紫薯提取液为原料，研究过滤模式（两步法和三步法）对蛋白质和多酚分离性能的影响。结果表明，2种操作模式都可以有效去除蛋白质，但是两步法（50．10kDa）比三步法（100～50—10kDa）可得到更低的多酚去除率（更高的多酚得率）。串联阻力模型分析表明，100kDa和10kDa膜主要的过滤阻力为膜阻力，而50kDa膜的全要过滤阻力为浓差极化阻力和滤饼阻力。

Ultrafiltration of purple sweet potato is carried out with membranes with molecular weight cut-offof 100, 50, 10 kDa. Filtration model with 3 steps and 2 steps are compared. The effect of filtration model on separation of protein and polyphenol was studied. Results showed that both filtration steps are efficient for protein removal, but 2 steps model （50-10 kDa） provided better polyphenol recovery than 3 steps model （100 kDa-50 kDa-10 kDa） . Resistance-in-series analysis showed that membrane resistance is the main resistance for 100 kDa and 10 kDa membrane, meanwhile, cake and concentration polarization resistance are the irnnnrtant far 50 kDa membrane.