Physico-chemical characterization of galactan exopolysaccharide produced by Weissella confusa KR780676

- Physico-chemical properties of a galactan exopolysaccharide from W. confusa were studied.
- Average particle size of galactan was found to be 549.81 d nm.
- Galactan showed high oil absorption capacity (5.09 mL/g).
- EPS possessed good emulsifying activity (69.4%) and emulsion stability (15 days).
- Galactan (0.2 mg/mL) exhibited flocculating activity (81.7%) at pH 4.0.

Physico-chemical properties of a galactan exopolysaccharide (EPS) produced by Weissella confusa KR780676 isolated from an idli batter were studied. In our previous paper, we had reported the isolation and characterization of a linear galactan (containing α-(1 → 6)-linked galactose units) isolated from an acidic fermented food. In this manuscript, we are reporting the physico-chemical properties viz., Colour evaluation (L* 81.79, a* 3.15, b* 15.04), flow properties (compressibility index 38.46%), syneresis, light transmittance (50.7% for 5 days), pasting properties (temperature 64.6 °C), texture (hardness 9.876 N) and particle size (549.81 d nm) for the galactan were carried out. This galactan also possessed high oil absorption capacity (5.09 mL/g) with good emulsifying activity (69.4%) and emulsion stability up to 15 days. Flocculating activity of 65.3-81.7% was observed with 0.2 mg/mL EPS in a wide range of pH (2.0-12.0). These functional properties will make the galactan EPS a good candidate for use as thickening and gelling agent and emulsifier to form long-term emulsions in food, pharmaceutical and cosmetic products, as well as for bio-treatment of wastewater and hydrocarbon-polluted environments.