Influence of three particle size (<180, 180, and 250 μm) of shallot flour on compositional, structural, rheological, and thermal properties were studied. Carbohydrate, starch, fiber, amylose, amylopectin, color, and other functional properties showed the indirect effect with an increase in particle size and were found to be higher in lowest particle size, whereas, protein, bulk, true density were lower and ash, fat, moisture, aw, was unaffected by particle size. Rheological properties at concentration (0.5, 1.0, 1.5, and 2.0% [w/w]), temperature (20, 30, 40, 60, and 80°C) and pH (4, 7, and 10) revealed Non‐Newtonian, shear thinning behavior of all samples with flow behavior index (n) <1 and coefficient of determination (R2) >0.90, using power law model. Examined pasting property showed higher viscosity values, holding strength and lower peak time and temperature for sample with lower particle size. Thermal parameters (T o, T p, and T c) and change of enthalpy ( ΔH) values increased with increase in particle size. Practical application A comprehensive study of rheological, thermal, and structural properties concludes application of shallot flour as a thickener in various food products. The particle size of shallot flour (<180 μm) was found to be most suitable for their application as a thickener, evident from proximate, physiochemical, functional, rheological, pasting, and thermal parameters. SEM results also reveal the application of shallot flour (<180 μm) as a thickener. Shallot flour can not only improve the texture of the food products as natural thickener but can also enhance the flavor profile.

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Shallot flour was prepared and sieved into three different particle sizes of \ 180 lm (sample A), 180 lm (sample B) and 250 lm (sample C). Effect of concentration [0.5%, 1.0%, 1.5% and 2.0% (w/w)], temperature (20, 30, 40, 60 and 80 °C), pH (4, 7 and 10) and freezing (-20 °C) on rheological properties of shallot flour were studied at increasing shear of 0.1-100 s -1 . Effect of dynamic change in temperature (15-95 °C) was also measured at constant shear rate of 50 s -1 . Power law (Eq. 2) model with coefficient of determination (R 2 ) above 0.90, well described the rheological behavior of the shallot flour as a shear thinning, non-Newtonian fluid at different concentration, temperature and pH. All the samples had n values below 1 and increase in viscosity or consistency index (k) value with increase in concentration of the sample was observed, while inverse relation was observed when temperature was increased. All samples showed increase in k value when the pH of the dispersion was varied from acidic to alkaline condition. Viscosity of samples were found unaffected even after freezing in freeze-thaw cycle. These data show sample A to be most suitable for their application as thickener, having highest k value. The obtained research provides information for utilization of shallot as a thickener in various food industries.