Figure 1.

Overview of main collagen products that can be obtained from natural sources (animal by-products) according to their origin (animal and tissue) and manufacturing process. Hydrolyzed collagens can be obtained from cartilage or other connective tissues through an enzymatic treatment to breakdown polypeptide chains. Undenatured (non-soluble) or soluble native collagen type II can be only obtained from cartilage, through soft temperature processes to maintain the triple helix structure intact.