Physicochemical and functional properties of gelatin from the skin of unicorn leatherjacket (Aluterus monoceros) as affected by extraction conditions

Abstract

Physicochemical and functional properties of gelatin from the skin of unicorn leatherjacket extracted at different temperatures for various times were determined. Yield, recovery and free amino group content of gelatin increased, but gel strength generally decreased as the extraction temperature and time increased (P < 0.05). All gelatins contained a! and a2 chains as the predominant components. FTIR spectra of all gelatins showed a significant loss of the triple-helix. Gels of gelatin extracted at higher temperature for longer time had larger strands with larger voids. At the same level of gelatin, emulsifying and foaming properties varied with extraction conditions. Emulsion activity index (EAI) of all gelatins decreased with increasing concentrations (P < 0.05). Nevertheless, the highest emulsion stability index (ESI) was observed at a level of 3% (P <0.05). Foam expansion (FE) and foam stability (FS) of gelatin generally increased as the concentration increased (P < 0.05). © 2012 Elsevier Ltd.