Effect of Acid Pretreatment Time on the Physicochemical Properties of Gelatin Produced from Silver Carp Skins
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
In this study, the effect of acid pretreatment duration on the physicochemical properties of gelatin from silver carp skins was investigated. The results showed that when the acid pretreatment time was increased from 10 to 80 min, the structure of silver carp skin was loosened; the high molecular weight fractions of collagen, including the β-chain, were susceptible to degradation during the hot-water extraction. The hydroxyproline content of the extracted gelatin was decreased from 61 to 43 residues per 1000 amino acid residues. The isoelectric point of gelatin from silver carp skins was approximately at pH 9.2, regardless of the duration of acid pretreatment. However, viscosity, gel properties, and film-forming ability of extracted gelatin were decreased after long acid pretreatment. When the acid pretreatment time was 10 min, the strength of prepared gelatin gel, the tensile strength, and the elongation at break of the prepared gelatin gel were 242.67 g, 28.24 MPa, and 65.52%, respectively. Based on circular dichroic analysis, the acid pretreatment time had no significant effect on the secondary structure of extracted gelatin. However, the longer the acid pretreatment time, the more difficult it became to form triple helical structures through renaturation route in the drying process of the gelatin solution, resulting in a decrease in film-forming ability.