Study on the Factors Influencing the Preparation of Orange Oil Nanoemulsion by High-pressure Microfluidization

Orange oil nanoemulsions were prepared by high pressure microfluidization technology to study the effect of emulsifier type and concentrations,homogenous condition(pressures and number of passes)on mean droplet diameter(MDD),turbidity and storage stability. Four types of emulsifier:Quillaja saponin(QS),modified starch(MS),whey protein isolate(WPI)and sodium lauryl sulfate(SDS)were used to prepare orange oil emulsion by high pressure microfluidization with different pressures and number of passes. The results showed that with the increasing of emulsion concentration in certain range,the MDD gradually decreased. The proper concentration for SDS,QS,WPI and MS in orange oil nanoemulsions were 2%,4%,4% and 8%,respectively. With the increase of homogenous pressure and number of passes,MDD and turbidity showed similar decreasing trends. The orange oil nanoemulsions had the smallest MDD(<150 nm)under condition of 22000 psi and 4 passes. MDD showed an exponential relationship with pressure. It was found that the phase viscosity ratio affected MDD. After storage experiment at 25 ℃ for 21 days,the orange oil nanoemulsions were physically stable.