Effects of oxidation and heat on the collagen fibers structure of the sea cucumber body wall during low-temperature long-time thermal treatment

NI Zhong; CHU Pengfei; LIN Ying; LIU Yuxin

doi:10.12187/2025.01.003

Abstract：Fresh sea cucumber was used as the object to study the effect of oxidation and heat on its texture properties during low-temperature(60 ℃)long-time thermal treatment.Then intact collagen fibers were extracted from the fresh sea cucumber body wall,and were subjected to oxidation,thermal treatment and the combination of both.Differential scanning calorimetry(DSC),cryo-scanning electron microscopy(cryo-SEM),fourier transform infrared spectroscopy(FTIR),electron spin resonance(ESR)were used to study the changes in thermal stability,microstructure,protein secondary structure,and oxidation degree of collagen fibers during low-temperature long-time thermal treatment.The results showed that single oxidation treatment had only oxidative degradation effect on collagen fibers,and single thermal treatment caused oxidation,denaturation,degradation and dissolution of collagen fibers.Oxidative synergistic thermal treatment resulted in more pronounced structural degradation and destruction of collagen fibers compared to single oxidation or thermal treatment.After one hour of oxidative synergistic thermal treatment,the proteoglycan bridge in collagen fibers was obviously broken.After 24 hours,a new thermal absorption peak appeared near from 15～24 ℃,indicating that the collagen fibers was gelatinized.With the prolongation of treatment time,the aperture of collagen fibers network was further contracted and broken.Oxidative synergistic thermal treatment promoted the oxidation degree of collagen fibers by thermal treatment,which resulted in the degradation of macromolecular proteins and the dissolution of soluble substances such as hydroxy proline and glycosaminoglycans(GAG).Therefore,oxidative synergistic thermal treatment can cause oxidation,denaturation,aggregation and degradation of collagen fibers,which in turn affects the textural properties of the sea cucumber body wall.