Hydrocolloids in emulsions: particle size distribution and interfacial activity

The emulsification properties of 14 hydrocolloid gums (propylene glycol alginate, gellan, carrageenan, pectin, methylcellulose, microcrystalline cellulose, gum arabic, locust bean gum, guar, xanthan, mustard, flaxseed, fenugreek, oat) were investigated. Gum dispersions were prepared in water (0.5%) and emulsified with 40% oil using a Polytron homogenizer. Emulsion stability was determined by centrifugation and storage time, surface and interfacial tension by Du Nouy ring, particle size by integrated light scattering and overall morphology by light microscopy. When compared to the other gums in this study, fenugreek produced a very stable emulsion. Fenugreek was more efficient than other gums in lowering the interfacial free energy, its emulsion was composed of very small oil droplets (70% < 1 mum) and under the light microscope appeared as uniform droplets with a narrow size distribution. (C) 2001 Published by Elsevier Science Ltd.