Study of the release of limonene present in chitosan films enriched with bergamot oil in food simulants

Chitosan films containing different concentrations of bergamot oil (BO) were obtained and the migration of limonene, the major oil component, to five liquid food simulants (aqueous solutions with 0%, 10%, 50% and 95% of ethanol and isooctane) was studied at 20 °C. The losses of BO and limonene during the film drying were also quantified. The release kinetics of limonene from chitosan matrix was described using an empirical model which relates the reduced concentration loss of limonene and the square root of time. The results show that kinetic constants for all films increased exponentially when the ethanol concentration increased in the aqueous system and were slightly greater when the film thickness was lower. Composite films remain intact in isooctane CH–BO and no release of limonene was observed. Hydration of the film to promote molecular mobility was essential to ensure the compound release.