Investigation of degumming treatments effect on the various physical and mechanical properties of Eri silk from Ethiopia

Eri silk, regarded as “peace silk,” is currently one of the most prized silks because of its softness, breathability, and sustained production. In Ethiopia, where Eri silkworm sericulture is budding, poor degumming practices often result in inferior fibers. This study, then, attempts to evaluate the effect of different degumming treatments on the physical and mechanical characteristics of Ethiopian Eri silk fibers toward fiber value addition and an opportunity for eco-friendly alternatives. Alkaline, enzyme, and hot water degumming performed on harvested cocoons from Addis Ababa, Arbaminch, and Hawassa, which were then subjected to SEM, FT-IR, DSC, and mechanical testing. One of the results showed that sodium carbonate was very effective in removing sericin but altered fiber structure, while water degummed fibers had sericin and rough fibers. Enzymatic degumming efficiently removed sericin without compromising the structure. FTIR confirmed little interference to fibroin in enzymatic treatment, establishing this as a potential sustainable method for improving the quality of Ethiopian Eri silk.