Investigation on the emulsifying properties of Persian gum as a novel food emulsifier

Persian gum (PG), an exudate of wild almond tree Amygdalus scoparia Spach, is one of the natural hydrocolloids which are mostly produced in Iran. In the present study, the emulsifying properties of its soluble fraction (SFPG): oil at various ratios [0.25:1 (E1); 0.5:1 (E2); 1:1 (E3); 2:1 (E4); 1:2(E5)] in comparison to Arabic gum (AG) as control [1:1 (CTL)] have been studied. The results have indicated that heat treatment has no effects on the stability of the of SFPG emulsions against AG emulsion. Among all of the emulsions, E4 has the highest emulsion stability index over 5 weeks (ca. 99% at fifth week androom temperature); moreover the measurement of optical density justifies the good emulsifying properties of E4 (0.8752 in 500 nmat fifth week) which is significantly more than CTL (0.3648 in 500 nm at fifth week). Particle size distribution of the samplesimmediately after preparation, illustrates that E4 and CTL has asimilar sharp curves with fine average droplet diameter (D [4,3] 0.8 μm); nevertheless at day 0, the emulsifying properties of E4 and CTL are similar, but during the storage for 5 weeks, E4 shows a higher stability than CTL.

Keywords:

Persian gum , Amygdalus scoparia Spach , Emulsification , Stability