Isolation and characterization of collagen from the muscle of Amur sturgeon (Acipenser schrenckii)

The collagen in Amur sturgeon muscle was isolated using sodium chloride (salt-solubilized collagen, SSC, 3.02%), followed by acetic acid (acid-solubilized collagen, ASC, 31.56%) and then pepsin (pepsin-solubilized collagen, PSC, 58.49%). The collagens appeared to be dense sheet-like film linked by random-coiled filaments under SEM. There was no obvious difference in denaturation temperature (about 33°C) assessed by CD, while the melting temperature of SSC (115.82°C) was significantly lower than ASC and PSC (120.23 and 118.80°C, respectively) determined by DSC. SDS-PAGE showed that the collagens were mainly type I with similar amino acid profiles. FTIR confirmed the triple helical structure of the collagens, and indicated more hydrogen bond in PSC and more intermolecular crosslinks in ASC. These results provide some basis for elucidating the function of collagen in the development of meat texture during postmortem aging and processing.