The gelling and melting temperature of flaxseed gum solution and its gel strength, gelmicrostructure were studied using rheological measurement, Differential ScanningCalorimetry (DSC), Atomic Force Microscopy (AFM) and Scan Electron Microscopy(SEM).The dynamic oscillatory measurement and DSC were excellent tools forcharacterizing gelling and melting processes of gel systems. Flaxseed gum solutionswere characterized with gelation properties at room temperature and formed athermoreversible gel. The initial cooling temperature largely influenced the gellingand melting temperature of flaxseed gum. The gelling temperature was lower than itsmelting temperature at the same initial cooling temperature. This might be due to thefact that the transformation from disordered arrangement to ordered network neededmore energy.The dissolution temperature, concentration, pH value and different valent mineralsalts affected the gel strength of flaxseed gum. The gel strength depended ondissolution temperature and concentration, which was also verified by AFM. The gelstrength was significantly influenced by pH. The maximum gel strength was obtainedat pH 6~8. The gel strength decreased with both lowering pH values between pH 2～6and with raising pH values above pH 8. Addition of monovalent cations (Na+)lowered the Zeta potential, thus decreasing the gel strength. Addition of divalent
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