Silver carp scale gelatins for the stabilization of fish oil-loaded emulsions

Herein, three types of silver carp scale gelatins were extracted, and their molecular weight distribution, structural properties, functional properties and emulsifying properties were investigated and discussed. Acetic acid-extracted gelatin (AAG), hot water-extracted gelatin (HWG), and pepsin enzyme-extracted gelatin (PEG) showed similar and four clear bands in sodium dodecyl sulfate-polyacrylamide gel electrophoresis pattern, whereas they showed different beta chain amounts and beta-sheet percentages. The water-holding capacity values (g/g of gelatin) were: AAG (16.8 +/- 1.1) > HWG (14.0 +/- 0.7) PEG (13.5 +/- 1.6). The fat-binding capacity values (g/g of gelatin) were: AAG (11.8 +/- 0.3) > HWG (9.5 +/- 1.3) > PEG (5.3 +/- 0.4). Emulsion droplet sizes and creaming index values decreased with the increase of gelatin concentrations for all the fish oil-loaded emulsions stabilized by three types of gelatins. Compared with PEG, AAG and HWG show similar and higher emulsion stability at high gelatin concentration (10 mg/mL). The stabilization mechanism of fish oil-loaded silver carp scale gelatin-stabilized emulsions involved an extraction method-protein molecular weight distribution-protein molecular structure-molecular interaction-emulsibility-droplet structure-emulsion stability mute. This work would be beneficial for the research on the relationship of structure and function of gelatin and to the comprehensive utilization of aquatic products.

Automated summary

In this study, three types of silver carp scale gelatins were extracted and characterized. Different extraction methods resulted in variations in the molecular weight distribution and functional properties of the gelatins. Gelatin extracted by acetic acid showed the highest water-holding and fat-binding capacities, while gelatin extracted by pepsin enzyme had the lowest emulsion stability. This research provides valuable insights into the relationship between gelatin structure and function, and may contribute to the comprehensive utilization of aquatic products.