Active packaging film of chitosan and Santalum album essential oil: Characterization and application as butter sachet to retard lipid oxidation

Chitosan with sandalwood (Santalum album) essential oil (SEO) using malic acid as solvent were evaluated as an active packaging film. It was applied as sachet to butter packaging. The effects of SEO concentration (0.5 %, 1 % and 2 % v/v) on chitosan film properties were studied by measuring the equilibrium moisture content, solubility, water vapor permeability (WVP), mechanical, optical, heat sealability, antioxidant properties, surface morphology and thermostability. SEO showed a significant effect on the film properties except for the puncture properties and the equilibrium moisture values. SEO promoted a significant decrease in tensile strength from 5.78 to 2.99 MPa, Young’s Modulus (YM) from 35.74 to 6.81 MPa, WVP from 6.70·10−11 to 3.34·10−11 g/m·s·Pa, and sealability from 195.20 to 107.94 N/m. The antioxidant properties of the films were improved with the presence of SEO. The addition of SEO significantly improved the UV-barrier of the films. The color and transparency of the samples showed significant variations by the addition of SEO. The active packaging film was evaluated as butter sachet. After 3 months of butter storage, a significant decrease of the thiobarbituric acid reactive substances was observed, showing a 36 % decrease in the lipid oxidation compared to unpackaged samples. The films are completely water-soluble and can be easily removed from foodstuffs after use without generating solid wastesThe authors appreciate the funding support of Xunta de Galicia, within the postdoctoral fellowship granted to Patricia Cazón Díaz (No. ED481B-2021–040). The use of RIAIDT-USC analytical facilities is acknowledgedS