**Abstract**

Industrial processing of bovine hides into leather results in many unusable hide off-cuttings, shavings and trimmings. This waste raw material is under-utilised and presents a waste valorisation opportunity to derive a high-value product such as collagen. Collagen is a highly sought-after protein which consists of three polypeptide chains, comprising 30% of the mammalian body's protein, being the main component of skin, connective tissue and cartilage. The demand for collagen is rising at approximately 20% annually and global collagen-based biomaterials market is predicted to reach US\$5 billion by 2025. This chapter presents a waste valorisation opportunity to extract collagen from waste bovine hide off-cuttings. Further, it discusses collagen extraction method optimization and methods used to investigate physicochemical properties of collagen are reviewed.

**Keywords:** collagen extraction, bovine collagen, bovine hide, acid-enzyme, solubilisation, extraction, waste valorisation
