<p>This research examined the structural and rheological properties of galactomannans extracted from alfalfa seeds. HPLC results revealed that alfalfa seed gum (ASG) was a heteropolysaccharide primarily consisting of mannose and galactose (1.08), and a high molecular weight of 4.02 × 10⁶&#xa0;g/mol as determined by gel permeation chromatography (GPC). The FT-IRspectra confirmed the presence of α-D-galactopyranose and β-D-mannopyranose units in the ASG molecule. The NMR observations revealed that ASG comprised repeating units of β-1,4-linked D-mannopyranose residues with D-galactopyranosyl joined by α-1,6 glycosidic linkages in the side chains. X-ray diffraction analysis indicated an amorphous nature for the ASG, whereas FE-SEM images revealed a uniform and smooth texture of ASG. The ASG dispersions (1, 2, 3, 4, and 5%) exhibited a strong shear-thinning character as described by the Power Law, Herschel-Bulkley, and Casson models. The viscosity of 2% ASG dispersion decreased by 58% with an increase in temperature from 25 to 80˚C. The gum dispersions demonstrated a pronounced thixotropic behavior, as indicated by a significant increase in the hysteresis loop area with increasing gum concentration. The frequency sweep test indicated a weak gel-like behavior, except for the 1% concentration, which showed a viscoelastic nature. The temperature sweep test confirmed no sol–gel transition. ASG could have a key advantage over commercial gums like guar gum owing to its large molecular size, monodisperse molecular distribution and amorphous nature, along with commendable pseudoplastic, and thixotropic behaviors, coupled with notable thermal stability contribute to enhanced viscosity, consistency, and gelling capacity, making it a promising candidate for various food industry applications. Novel gums like ASG may be used in food products under varying processing conditions, such as temperature within food systems.</p>