Ginger essential oil nanoemulsions: Preparation and physicochemical characterization and antibacterial activities evaluation

The aim of this study was the preparation of ginger (Zingiber officinale) essential oil nanoemulsions through the bottom up solvent displacement technique. The effects of main processing parameters, namely, the homogenization and evaporation rotating speeds at solvent removing step were also evaluated on mean particle size, polydispersity (PDI), zeta potential, turbidity, antioxidant, and antibacterial activities against S. aurous and E. coli of gained nanoemulsions, using response surface method (RSM). The ginger essential oil nanoemulsions were successfully synthesized, in the particle sizes ranged from 68 to 1,035 nm. The second polynomial models were then suggested in order to predict the studied response characteristics by selected process independent parameters. The multiple graphical optimization suggested that using mixing the organic and aqueous phases in the ranges of 800-1,000 rpm and rotating evaporator at the speeds from 75 to 85 rpm would lead to production of the most desirable nanoemulsions. The observed insignificant differences between the experimental data and calculated ones by models confirmed the suitability and accuracy of suggested models. Thus, it was concluded that the prepared nano-sized ginger essential oil can be effectively used in several food systems as preservative or flavor modifier agent. Practical Applications The ginger essential oil nanoemulsions were fabricated through a cost effective and simple nano-precipitation technique and the gained nano-sized, water dispersible, chemically stabilized product with desired flavor and good either antioxidant or antibacterial activities, can be successfully used in various food and beverage formulations as preserver, nutrition enhancer and flavor.