Eco-friendly enzymatic dehairing on animal hides

Abstract

This study presents the development of enzyme-assisted and enzyme-mediated methods as an alternative and eco-friendly approach to minimize the use of chemicals that will reduce the environmental impact in the manufacturing of leathers. Two types of protease namely alkaline protease 50a and keratinase were used in the enzymatic application in dehairing. Four sets of experiments of cow hides were performed. The sets included the use of chemicals which are 5% calcium oxide (CaO) and 2% sodium sulfide (Na2S), the use of 2.5% enzymes with 5% CaO, the use of two types of enzymes and the use of the single enzyme. The hides which undergo treatment with enzymes eliminated 85% of hair after 26 hours under shaking condition at 37 °C while the treatment with enzyme together with 5% calcium oxide eliminated 100% of hair under the same conditions. The treatment of Na2S along with CaO also eliminated 100% of hair faster than the other two treatments. As revealed by Scanning Electron Microscopy (SEM), the surface of the hides that were treated with enzymes was smoother and silkier than hides that were treated by chemicals. Hence, these result revealed that the enzymes-assisted method could be implemented in commercial leather manufacturing to reduce the use of severe Na2S. The application of enzyme-assisted technique can help in the minimization of pollutions in the environment and can be a good alternative for the production of good quality of leather.