Preparation and Characterization of Edible Coating and Film Composed of Sodium Alginate/Ylang-Ylang Oil/Cellulose Nanocrystals Pickering Emulsion and Delayed Post-Harvest Spoilage of Mandarin (Citrus Reticulata) Fruit

Abstract

Alginate (Alg) films with improved water vapor permeability (WVP), mechanical properties, and ultraviolet (UV) barrier were prepared with ylang-ylang oil (YYO) Pickering emulsion (PE). Cellulose nanocrystals (CNCs) were used as natural stabilizers to prepare YYO PE. The final coating comprised 1% Alg (alginate), Alg/0.24% CNCs, and Alg/0.5% YYO Pickering emulsions. The impacts of YYO-PE on the properties of Alg films were investigated, and their effects on post-harvest control of mandarins were evaluated.  Gas chromatography-mass spectrometry (GCMS) was used to identify the components of YYO. AFM and SEM showed an increase in the roughness of the films containing the Alg/YYO PE. The FTIR analysis revealed no new interactions in the Alg/YYO PE films. Moisture content (MC) and thermal properties were lower for Alg/YYO-PE films. The Alg/YYO-PE coating lowered the weight loss (7.84 ± 1.76%) and inhibited (p < 0.05) the growth of Penicillium italicum (P. italicum) and Penicillium digitatum (P. digitatum). The inhibition percentages were 56.02% and 47.98%, respectively, for the inoculated mandarins. In conclusion, the Alg/YYO PE coating and film have the potential to be an eco-friendly active packaging material in the food sector.

Keywords: Edible coating and film, Ylang-ylang oil Pickering emulsions, cellulose nanocrystals, Fungal decay, Mandarin preservation