摘要：目前双重乳液技术已应用于许多食品。食物中的一些天然成分如蛋白质等具有天然乳化剂的作用，不添加乳化剂形成的乳液结构食品有更高的食用级别。本次研究探索双重乳液（W/O/W）在天然食品原料中即不添加二级乳化剂的情况下的形成及盐对W/O/W双重果蔬浆乳液结构及稳定性的影响。结果表明：不添加第二级乳化剂及内外水相分别含KCl 及NaCl 时，O/W乳液、W/O/W乳液能够在一些果蔬浆中形成，形成的双重乳液W/O/W在草莓和柠檬果浆中更稳定。在草莓果浆W1/O/W2中，分散相W1/O 液滴的粒径大小随加入果浆体积比例的减少而增大。KCl或NaCl 的加入对于某些食品中形成优质双重乳状结构非常关键。此外，均质速度及时间同样影响果蔬浆乳液的结构和稳定性。
Effect of Salt on the Structure and Stability of W/O/W Double Fruit/Vegetable Puree Emulsion
（Henan University of Animal Husbandry and Economy，Zhengzhou 450000，China）
Abstract: Double emulsions are applied in many food products at present. Some natural ingredients in food such as proteins are natural emulsifiers，formed in food materials in the absence of emulsifier increase products to food grade. This study explored the formation of double emulsion（W/O/W）in natural food materials without the addition of secondary emulsifiers and the effect of salt on the structure and stability of W/O/W double fruit or vegetable puree emulsions. The results showed that O/W emulsion and W/O/W emulsion could be formed in some fruit and vegetable puree without the addition of the secondary emulsifier while the internal and external aqueous phases containing KCl and NaCl respectively. Strawberry and lemon double emulsions were more stable than orange double emulsions. In strawberry W1/O/W2 emulsion，the particle size of W1/O droplets increased as the volume ratio of the puree decreased. The addition of KCl or NaCl was critical to the formation of high- quality double emulsions in certain foods. In addition，the homogenization speed and time also affected the structure and stability of the fruit and vegetable puree emulsions.
Key words: double emulsion；salt；emulsion structure；emulsion stability
（2020年 第23卷 第3期）