Formation of heat-resistant nanocapsules of jasmine essential oil via gelatin/gum arabic based complex coacervation

The formation of heat-resistant flavor nanocapsules was achieved by gelatin and gum arabic based complex coacervation. The colloidal behavior of complexes was investigated using turbidity titration (600 nm) with the help of an in situ acidifier – glucono-δ-lactone. The soluble complexes formed at a quite narrow pH range, and pH 4.80 under the mixing ratio of 1:1 (gelatin/gum arabic, w/w) was favorable for the nanoparticles preparation. Subsequently, corresponding nanocapsules with jasmine essential oil entrapped were successfully prepared and cross-linked by transglutaminase. Their heat-resistance capability against 80 °C was evaluated by both structural characteristics (size, polydispersity index and zeta potential) and flavor analysis. The results showed that the nanocapsules cross-linked at alkaline conditions could endure the water bath of 80 °C for 7 h. However, the analysis of volatile compounds by GC–MS revealed that their flavor profiles of jasmine essential oil began to destroy above 5 h.