Kinetic modeling of quality changes in high-protein bars containing Arabic and Persian gums: Physicochemical, textural and FTIR analyses

• Kinetic modeling was applied to predict storage-related changes in protein bars. • Arabic and Persian gums enhanced moisture retention and reduced texture hardening. • Rational and Gompertz models best described moisture and hardness kinetics. • FTIR revealed α-helix loss and β-sheet aggregation linked to bar hardening. • Hydrocolloids improved structural stability and shelf-life of high-protein foods. High-protein nutrition bars undergo physicochemical and structural changes during storage, which can affect their quality and consumer acceptance. This study examined the evolution of moisture content, water activity, hardness, browning index, and protein secondary structure in a control protein bar and an optimized formulation containing Arabic ( Acacia ) and Persian ( Prunus scoparia ) gums. Samples were stored at 25°C and analyzed on days 0, 7, 14, 21, and 28. Fourteen kinetic models were fitted to the time-series data in MATLAB, and model performance was evaluated using R², χ², mean bias error (MBE), and RMSE. Compared with the control, the gum-fortified formulation retained more moisture, exhibited a smaller increase in hardness, and showed less browning during storage. FTIR analysis of the amide I region indicated a decline in α-helix content and an increase in β-sheet structures, consistent with the observed textural firming over time. The Rational, Gompertz, Harris, Fourier, and Logistic models provided the best empirical fits for moisture, water activity, α-helix, β-sheet, and browning index kinetics, respectively. Overall, the kinetic modeling offered a useful description of early storage changes and may assist in quality monitoring, although validation over extended storage periods is recommended.