Effects of a curcumin nanoemulsion on the physico‐chemical properties of chitosan‐based films

Summary Chitosan (CH)‐based films were incorporated with a curcumin nanoemulsion (CurNE) to overcome their limitations, such as low mechanical strength and high‐water vapour permeability (WVP). The obtained optimum conditions of NE were, as follows: oil to aqueous phase ratio = 1:9 and ultrasonication time = 15 min, given that the smallest mean diameter and the highest absolute value of the zeta potential were 307.53 ± 6.30 nm and −15.43 ± 0.74 mV. Thereafter, NE was encapsulated in CH(CH–NE) to determine the functional amelioration, as well as the alteration in the inner structure. CH–NE demonstrated the successful fabrication of uniform and compatible films, which reinforced elongation and significantly decreased the WVP. Furthermore, the antioxidant activity of CH–NE was five times higher than that of CH. The thermal and electrical properties were evaluated to elucidate the alterations in the inner structure alterations. Further, the glass‐transition temperature ( T g ) of CH–NE shifted by ˜10 °C and the relaxation time (τ) of the electric modulus increased compared with that of CH, indicating that the incorporation of NE affected the structural alterations.