The film of aliginate calcium gal and the pre -disposition of oilly liquid can prevent shrinking or breaking of juice sac,but if the operation was not suitable ,discoloring may be caused.

• 海藻酸钙凝胶薄膜和含油溶剂预处理能很好地防止汁胞的萎瘪破碎,但操作不当容易造成褪色。