Natural Polymer from Sesamum radiatum as an Emulsifier and Stabilizer in Fabrication of Macroemulsions

Aim: Sesamum gum was extracted from the leaves of Sesamum radiatum and evaluated as emulsifier or stabilizer in coarse emulsions.

Methods: The emulsion systems were assessed by monitoring of emulsion density, viscosity, globule size, and by evaluating the effects of temperature and salt over a four week period.

Results: It was observed that the known 4:2:1 ratio did not form emulsions when sesamum was used but other ratios such as 2:4:1, 2:4:0.5, 2:4:0.25 and 2:4:0.125 formed emulsions. The emulsions were however, unstable. When sesamum gum was used as a stabilizing agent (0.4%w/v – 2.0%w/v), and acacia (7.5%w/v) as an emulsifying agent, stable emulsions were formed. At the end of four weeks, the emulsion systems exhibited lower globule sizes (1.68-1.95 µm) than the emulsion systems containing acacia alone (3.95 µm) as emulsifier. The emulsions creamed or cracked when exposed to temperatures of about 40°C over 4 weeks. They were however stable even in the presence of salt of 1.0%w/v concentration.

Conclusion: The presence of sesamum as a stabilizer influenced the globule size and size distribution, the viscosity and consequently the stability of the emulsions. The study suggests that sesamum gum possesses the desirable properties of emulsifier/stabilizer in emulsions.