高压微射流制备橙皮精油纳米乳液影响因素研究

本文探讨了乳化剂类型、浓度和均质条件(压力和均质次数)对橙皮精油纳米乳液平均粒径(mean droplet diameter,MDD)、浊度以及贮藏稳定性的影响。采用四种乳化剂(皂树苷,QS;变性淀粉,MS;乳清分离蛋白,WPI;十二烷基硫酸钠,SDS),经高压微射流经不同均质压力和均质次数制备橙皮精油纳米乳液。结果表明,在一定范围,随着乳化剂浓度增加,MDD会逐渐减小,而SDS、QS、WPI和MS合适的浓度分别为2%、4%、4%和8%(w/w)。随着均质压力和均质次数增加,纳米乳液MDD和浊度都呈现较相似的减小趋势,在压力和次数分别增加到22000 psi和4次时,四种纳米乳液粒径可小于150 nm。研究发现,均质压力与MDD近似指数关系,乳液的相黏度比也会影响其MDD。贮藏实验表明,经25 ℃贮藏21 d,四种纳米乳液MDD基本稳定。

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.