Enhancement of Emulsifying Properties of Cuttlefish Skin Gelatin by Modification with N-hydroxysuccinimide Esters of Fatty Acids

Abstract

Cuttlefish (Sepia pharaonis) skin gelatin modified with N-hydroxysuccinimide esters of various fatty acids including capric acid (C10:0), lauric acid (C12:0), and myristic acid (C14:0) at different molar ratios was characterized and determined for emulsifying property. Fatty acid esters were incorporated into gelatin as indicated by the decrease in free amino group content. Gelatin modified with fatty acid ester had the increased surface hydrophobicity and emulsifying property with coincidental decrease in surface tension. Gelatin modified with fatty acid ester of C14:0 showed the highest surface activity, especially with the high degree of modification. Emulsion stabilized by gelatin modified with fatty acid ester of C14:0 had a smaller mean particle diameter with higher stability, compared with that stabilized by the control gelatin (without modification). Emulsion stabilized by modified gelatin remained stable at various pH (3–8) and salt concentrations (NaCl 0–500 mM). Emulsion was also stable after being heated at 50–90 °C for 30 min.