Physical properties of chitosan-basil essential oil edible films as affected by oil content and homogenization conditions

This work studies the influence of basil essential oil, its content and the homogenization treatment on the physical properties of chitosan-based edible films. Two homogenization treatments were applied, without (H1) and with (H2) microfluidization (MF). Composite films were softer, less rigid and more stretchable than pure CH films. MF intensified these changes. H2 films showed microcracks due to the weak interactions between chitosan and oil, which affected their mechanical behaviour. In pure chitosan films, MF significantly increased water vapour permeability. Homogenization treatment greatly affected this property. Gloss was reduced by the essential oil addition, whereas MF tended to yield glossier films.