Evaluation of physical properties and stability of water-in-oil-nanoemulsions containing saffron extract

Due to its distinct color, flavor and beneficial compound, the Saffron plant is extensively used in pharmaceutical and food industries, but because of its sensitive nature, its active compounds are lost in adverse environmental conditions. In this research, the preparation of water-in-oil nanoemulsion containing saffron extract was studied as an effective method for maintaining active compounds of saffron. For this purpose, nanoemulsions were synthesized by using span 80 and tween 80 as emulsifiers in three levels of 10, 12.5 and 15 percent, using ultrasound. The amount of aqueous phase (saffron extract with 12% dry matter) was 15% (wt) in all formulations and n-decan used on three levels: 70, 72.5 and 75% as oil phase. Particle size, polydispersity index and stability of each formulation at light conditions during 28 days after production were evaluated. The results showed the particle size and polydispersity index in the emulsion containing 15% emulsifier was less than the other emulsions and did not change in terms of physical stability.