Thermal Stability of Chicken Keel Bone Collagen

Acid‐soluble and pepsin‐solubilized collagen were isolated from chicken keel bone and analyzed by electrophoresis and circular dichroism. The denaturation temperature of chicken keel bone was determined by circular dichroism and compared to denaturation temperature of black drum or alligator bone. Our results show that collagen from chicken keel bone is a mixture of type II and type I, has predominantly the amino acids glycine, proline and hydroxyproline, and its secondary structure is predominantly triple‐helix. The onset of the denaturation temperature is 37C; at 44C, 50% of the collagen is denatured and the denaturation is complete at 48.8C making it the highest of vertebrate collagen denaturation temperatures reported in the literature. The high heat stability of chicken keel bone collagen may be in part ascribed to its imino acid content. Because of the high heat stability and low methionine content, chicken keel bone collagen is a high value‐added product with several biochemical and biomedical applications. PRACTICAL APPLICATIONS: The denaturation temperature of chicken keel bone collagen is above body temperature and allows applications in cosmetics where other types of collagen may be denatured because of their low denaturation temperature. Chicken type II collagen is well tolerated by patients with rheumatoid arthritis and is effective in the treatment of rheumatoid arthritis. Methionine‐restricted diet inhibits the growth of solid tumor such as gastric cancer, glioblastoma, medulloblastoma and neuroblastoma. Chicken type collagen may be a medical food for patients with solid tumors mentioned above.