In this paper, the physico-chemical characteristics of sage seed gum (SSG) were determined in terms of chemical compositions (moisture, total protein, total ash, minerals, total carbohydrate, total uronic acids), rheological properties, and surface activity. Monosaccharide compositions, molecular weight parameters and FTIR analysis also provided further structural information on the polysaccharide gum. The SSG had, on average, 11.24% (w.b.) moisture, 9.20% (d.b.) ash, 2.08% (d.b.) protein, 69.01% (d.b.) carbohydrate and 30.2% uronic acids. Mineral content of SSG was comparable to commercial gums except for potassium content which was higher in SSG. The chromatographic and FTIR analyses revealed that the SSG polysaccharide is a galactomannan with a 1.78-1.93:1 mannose/galactose ratio and a weight average molecular weight of ~4105 Da. Although SSG exhibited lower molecular weight and radius of gyration compared to guar gum, the values of intrinsic viscosity were the same. Under steady and dynamic shear tests, SSG demonstrated a strong shear-thinning behavior and a typical of weak gel characteristic, respectively, which were more pronounced than most commercial gums. The FT-IR spectra of the SSG polymer showed the presence of carboxyl groups, which may serve as binding sites for ions. SSG exhibited the ability to reduce the surface tension of water at concentrations lower than 0.25%. The current study provides new information on sage seed gum, which will be invaluable for explaining its unique functional properties

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