Pages 185–187
Abstract
Research summary supplied by the authors
India’s leather industry depends substantially on imported vegetable tannins such as mimosa, quebracho and chestnut extracts, resulting in high production costs and vulnerability to international supply fluctuations. Meanwhile, several Indian industries—including fruit-processing, juice and beverage units, nut-processing mills, areca and plantation-based industries—generate large quantities of polyphenol-rich by-products that remain underutilized. These materials, including, babul seedpod by-products, areca husk fractions, cashew husk extracts and other plant-derived industrial sidestreams, are rich in natural tannins and bioactive compounds with strong collagen-binding characteristics. This study investigates the conversion of such industrial by-products into indigenous vegetable tanning agents to strengthen domestic raw-material security. Extracts obtained through standardized hotwater extraction and filtration showed high phenolic content and demonstrated excellent tanning behaviour. When applied to pelt, these extracts imparted desirable properties such as improved firmness, fullness, and lightfastness, comparable to commercial vegetable tannins. Their application in combination tanning systems also yielded stable grain patterns and high-quality crust leather, confirming their suitability for industrial leather processing. The significance of this work lies in establishing a resource-recovery model that transforms underutilized by-products from other industries into high-value tanning materials. This supports national import substitution, reduces cost dependency, and promotes cross-sector collaboration between the leather sector and allied processing industries. The approach enhances sustainability by reducing waste burden while generating new revenue streams from materials traditionally treated as low-value residues. Overall, this study highlights the potential of India’s diverse industrial by-products to serve as reliable, cost-effective, and sustainable alternatives to imported vegetable tanning agents.