Evaluation of cashew tree gum (Anacardium occidentale L.) emulsifying properties

Cashew tree gum (CG) has been mentioned as potential alternative to replace Arabic gum (AG) in food applications. This study aimed to comparatively investigate the emulsifying properties of CG and AG. Emulsions were evaluated regarding particle size distribution (PSD), zeta potential, electric conductivity, turbidity, optical and confocal microscopy, creaming and rheology. The emulsions prepared using CG and AG presented volume-weighted mean diameter (D4,3) of 2.9 and 1.6μm, surface-weighted mean diameter (D3,2) of 2.3 and 1.5μm and dispersion index of 1.4 and 0.8, respectively. The apparent viscosity of CG emulsions were lower than AG emulsions. Furthermore, emulsions with CG and AG presented zeta potential of 1.3 and-23.4mV, cloudiness of 218 and 390cm-1 and electrical conductivity of 0.22 and 0.20mS/cm, respectively. Regarding to the emulsion stability, only from the fifth day of storage it was observed the rising of serum phase of both emulsifiers (CG and AG) indicating emulsion instability. Finally, it can be concluded that the cashew tree gum has good emulsifying properties in liquid emulsions being a promising ingredient to be used in beverage emulsions. © 2014 Elsevier Ltd.