The most prevalent extracellular matrix protein in the animal kingdom, collagen, is a member of the fibrous protein family that helps tissues transmit weight and gives cells a highly biocompatible environment. Collagen is the ideal biomaterial for implantable medical devices and scaffolds for in vitro testing systems due to its great biocompatibility. Mammal skin and tendon, which are rich in collagen, are rigorously processed by physical and chemical techniques to produce collagen-based solutions, porous sponges, membranes, and threads for surgical and dental uses or cell culture matrices. Other tissues, including the pericardium and the intestine, are decellularized more gradually while retaining their intricate collagenous structures. To create structurally adaptable materials with a variety of uses, tissue processing methods are organised as a sequence of phases. Sterilization procedures are carried out with the production of porous materials using various drying techniques. Casting processes like as spinning, moulding, or additive manufacturing techniques are combined with chemical crosslinking. Using collagen-based bio-inks, which can be shaped into 3D structures and coupled with live cells, significant advancements are anticipated. In particular, the thermal, physical, and sensitivity to enzymatic degradation consequences of the processing steps on the final materials attributes are reviewed. These characteristics are essential for handling, metabolization, and biological and therapeutic use.