The Effect of Amylose on Structures and Properties of Chitosan-Vanillin Films

This study experimentally investigates the effect of changes in amylose-to-amylopectin ratio on the multi-scale structures, hydrophilicity, and thermal properties of starch–chitosan essential oil (EO) films incorporated with vanillin. The results indicate that aggregates and uneven structures tend to form in the EO films with a higher proportion of amylose. In Fourier transform infrared spectroscopy, as the chitosan content increases, the wavenumber of stretching vibration of hydroxyl and the bending vibration of amino groups decrease, while the wavenumber of stretching vibration of C-O increases. Furthermore, with an increase in the chitosan content, the changes in the starch–chitosan EO film structure impacts the hydrophilic trend, and the hydrophilic changes in the EO films with common starch and G80 starch are significant changes with the proportions of starch to chitosan from 7:3 to 5:5. When their mass ratio is 3:7, the starch–chitosan EO films investigated exhibit the lowest decomposition peak temperature.