Investigation of the stability and homogeneity of Nigella Sativa oil-in-water emulsion

Abstract

In this study, the emulsion stability of Nigella Sativa (NS) emulsion in the presence of Tween 80 (T80) as surfactant at concentration range from 0.25 wt% to 3 wt% was carried out. The effectiveness of T80 for producing stable NS oil-in-water emulsion was characterized in terms of their creaming index, phase separation and fourier transform infrared spectroscopy (FTIR). Results showed that the lowest concentration (0.25 wt%) of surfactant was not enough to avoid phase separation during emulsification while the highest surfactant concentration (3 wt%) shows no obvious different with 2 wt% of T80. NS oil-in-water emulsion containing 2 wt% of T80 concentration showed the optimal parameters with the longest stability of 24 h and demonstrated 0% creaming index of emulsion. In addition, the FTIR spectra showed the transmittance peak at 1746 cm-1 and at 1599 cm-1 of NS/T80 was shifted compared to NS alone, indicating the interaction between NS and T80 via changing of hydrogen bond. This study provides valuable information into the effect of surfactant concentration for producing stable NS oil-in-water emulsion with significant stability properties, which potentially useful for the formulation of food-based products.