Casein and transglutaminase‐mediated modification of wool surface

In this study, casein, a protein found in milk, was used as a surface‐coating material for improving wool fabric properties mediated by a microbial protein cross‐linking enzyme: transglutaminase (TGase). For the wool fabric used in this study, 4% casein (owf) treatment for 1 h combined with 20 U/g fabric of microbial TGase reduced the area shrinkage of the KMnO 4 ‐pretreated wool fabric from 11.32±0.26 to 4.57±0.15%. The tensile strength increased from 275±5.0 to 315±2.1 N. The casein cross‐linked by TGase on wool exhibited better stability than that with the inactivated enzyme in warm water, Na 2 CO 3 and SDS solutions. Scanning electron micrographs demonstrated that the casein and TGase treatment smoothened the wool fiber surface by coating or filling the raised scales of the wool.