Effect of process conditions on the production of nanocomposite films based on amaranth flour and montmorillonite

•The effect of CMMT and TP on the properties of amaranth flour/clay films was studied.•The optimization methodology employed in this work was satisfactory.•MMT addition to films moderately improved mechanical properties and solubility.•WVP of the nanocomposites decreased by 96% of the original value with MMT addition.•Young's Modulus experimental data was compared with the Halpin-Tsai model.

This study investigated how the nanoclay content (CMMT) and process temperature (TP) affected the production of amaranth flour/clay nanocomposite films. The developed methodology involved preparation of a casting suspension at montmorillonite (MMT) concentrations ranging from 0 up to 9.7 g/100 g of flour and used 25 g of glycerol/100 g of flour, which afforded easily manageable films. Statistical analysis of the results was conducted by the response surface methodology and desirability function, and the optimal process conditions for film formation were determined. Both CMMT and TP influenced the mechanical properties and solubility of the films. MMT addition to the nanocomposite films formulation improved the mechanical properties and the solubility moderately, but it significantly reduced the water vapor permeability (WVP). This indicates that the nanoclay restructured the starch phase, as verified by differential scanning calorimetry (DSC) measurements. The desirability function employed here allowed for the establishment of the optimal process conditions, which were CMMT = 9.4 g/100 g of flour and TP = 83 °C, and proved to be an effective tool for this type of study.