Preventing moisture transfer in a composite food using edible films: Experimental and mathematical study

Water barrier properties of various edible films: acetylated monoglycerides (AMG), dark chocolate (DC), and wheat gluten (WG) were evaluated through water sorption isotherm, diffusivity, and permeability measurements. Diffusivity and sorption isotherm were then used in a mathematical model for predicting moisture transfer evolution in composite foods. It was successfully validated in agar gel/sponge-cake systems with the studied films at the interface. Using model predictions and relevant permeability measurement comparisons, AMG appeared to be the most efficient water vapor barrier films. Acetylation of monoglycerides seemed to be favorable to improve their water vapor transfer resistance mainly by reducing water solubility and despite a slight increase of water vapor diffusivity.