Effect of vitamin C load on preparing water in oil microemulsions using spontaneous method

Water in oil emulsions could be used for preparing low fat food products or encapsulating water soluble sensitive constituents. In this research, vitamin C loaded water in oil microemulsions prepared using spontaneous method without any co-surfactant. In spontaneous method, microemulsions are formed based on surfactant affinity toward continues phase and are thermodynamically stable. Results showed that by increasing vitamin C concentration, droplets size of emulsions increased from 66.7 nm for pure water to 214.3 nm for 3% loaded microemulsions and poly dispersity index increased from 0.15 to 0.501. Visual appearance of microemulsions changed from transparent for pure water containing microemulsions to opaque for 3% vitamin C loaded emulsions. By increasing vitamin C concentration, viscosity decreased from 115.4 to 87.9 mPa.s. This research showed that up to 3% vitamin C containing microemulsions could be prepared without co-surfactants.