Effect of particle size on compositional, functional, pasting and rheological properties of commercial water chestnut flour

Abstract

Effect of particle size on compositional, functional, pasting, thermal and rheological properties of commercial water chestnut flour (WCNF) was studied. The water holding capacity (WHC), oil holding capacity (OHC) and sediment volume fraction decreased with decreasing particle size and both WHC and sediment volume fraction of all samples increased rapidly at 70 °C, affecting viscoelastic properties of WCNF. The lightness (L) value increased to maximum when the particle size was reduced from 88 to 74 μm. The dough exhibited predominating solid-like behavior (elastic modulus, G′> viscous modulus, G″). The G′ increased significantly with increasing temperature (55–85 °C) and the particle size (74–88-μm) at the frequency range of 0.1–10 Hz. The viscoamylographic peak viscosity of whole was 1186 and the value increased to 1218 for the finest particle size while as the corresponding peak temperature decreased. Thermal analysis of different WCNF particle dispersions indicated two distinct endothermic transitions corresponding to the gelatinization of starch and melting of starch-natural lipid complex, respectively. This comprehensively conducted study on functional, pasting and rheological properties of commercial water chestnut flour as influenced by particle size would be helpful in optimizing gluten-free product development for celiac patients.