Thermal denaturation of fish collagen in solution: A calorimetric and kinetic analysis

• Thermal denaturation of fish collagen in solution was studied by non-isothermal DSC.
• Isoconversional and multivariate non-linear regression methods were applied.
• The optimal operating temperature of snakehead skin collagen was below 10 °C.
• The operating temperature should be controlled lower than conventionally determined.
• Thermal kinetic analysis was a valuable tool to understand collagen thermostability.

To further understand the thermal stability of fish collagen in solution, the thermal denaturation of collagen from the skin of snakehead (Channa argus) was studied by differential scanning calorimetry. Isoconversional and multivariate non-linear regression (Multivar-NLR) methods showed that the thermal denaturation behavior of fish skin collagen solution (FSCS) could be best described by a three-state model (a reversible step followed by an irreversible one), which approximated to single-step process at low heating rate (β) or low temperature. FSCS had relatively lower denaturation temperature (Tmax), enthalpy and apparent activation energy than bovine hide collagen under the same conditions. Based on Multivar-NLR, Tmax (β=0.001 K/min) of FSCS was simulated to be 21 °C, comparing with Tmax (β=2–8 K/min) (30.4–32.2 °C); however, the optimal operating temperature of FSCS would be below 10 °C for anti-denaturation, indicating that FSCS should be handled at much lower temperature than conventionally determined.