| Summary: | In this present study, the thermodynamic and thermal properties of glycerol and nisin-incorporated gum ghatti (GG, <i>Anogeissus latifolia</i>)-based films were determined. The films exhibited type III isotherm behaviors. Moisture content (MC) of films was increased with increasing water activity (<i>a</i><sub>w</sub>) and decreased with higher temperature. The incorporation of glycerol and nisin increased the sorption ability of GG films. The net isosteric heat of adsorption (<i>q</i><sub>st</sub>) and differential entropy (<i>S</i><sub>d</sub>) were decreased with increasing MC, showing an exponential negative correlation between them. Spreading pressure (<i>φ</i>) was increased with increasing <i>a</i><sub>w</sub>, but decreased with higher temperature. This incorporation of glycerol and nisin increased the <i>q</i><sub>st</sub>, <i>S</i><sub>d</sub> and <i>φ</i> of the GG films. The sorption behaviors were enthalpy-driven and non-spontaneous processes. The glass transition temperature (<i>T</i><sub>g</sub>), critical MC and <i>a</i><sub>w</sub> of the films were decreased, and increased respectively with the incorporation of glycerol and nisin. This work provides a theoretical basis for the application of edible films in fresh food preservation.
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