An integrated process for effective utilization of collagenous protein from raw hide trimmings: Valorization of tannery solid wastes

Abstract

This study aimed to convert raw hide trimming waste into high-value collagenous products, thereby addressing solid waste problems and generating economic value. Processing parameters such as the effect of acid concentration on gelatin extraction and the effect of enzyme concentration/hydrolysis time on the extraction of collagen hydrolysate (CH) from raw trimming were optimized. These process parameters were then integrated to extract gelatin and CH sequentially from raw trimming wastes. The process produced ∼55% as gelatin with a gel strength of 230 ± 8 g and a molecular weight fraction ranged between 50 and 200 kDa. The remaining collagenous matrix (after gelatin extraction) was recovered as CH with a yield of 97% (based on available collagen) consisting of molecular weight fractions ranging from 598.31 to 6236.12 Da. The produced gelatin and CH met the requirements for high-value applications in the food, cosmetic, and pharmaceutical industries. The study demonstrates an efficient process for utilizing collagenous proteins from raw hide trimmings and valorizing tannery solid wastes.