Division of Human Nutrition, Wageningen University & Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands; Physics and Physical Chemistry of Foods, Wageningen University & Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
Physics and Physical Chemistry of Foods, Wageningen University & Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
Food Res Int. 2018 May;107:148-157. doi: 10.1016/j.foodres.2018.02.021. Epub 2018 Feb 12.
In this study the effect of various emulsifiers (whey protein isolate (WPI), Na-caseinate, and Tween 20) and thickeners (xanthan and pectin) present in the outer water phase, w, on oil droplet size and yield of the inner water phase, w, of (w/o/w) double emulsions was investigated. Double emulsions stabilized by Tween 20 had smaller oil droplet sizes and higher yields in comparison to emulsions stabilized by WPI and Na-caseinate. Gelation of the inner water droplets w increased yield by 20% for all emulsifiers. Upon the addition of thickeners, the increasing viscosity of the outer water phase, w, facilitated oil droplet breakup. This resulted in smaller oil droplets and lower yields. When pectin was used as a thickener, in comparison to xanthan, an additional decrease in yield was observed. The yield decreased to values close to zero indicating that all inner water droplets w were lost during emulsification. We conclude that type of hydrophilic emulsifier, properties of inner water droplets, viscosity ratio of continuous and dispersed phase, as well as type of thickener influence oil droplet size and yield of w phase of double emulsions. This work provides a better understanding of how composition influences the properties of double emulsions and how this can be used to design double emulsions as fat replacers in more complex food systems.
在这项研究中，研究了外水相（w）中存在的各种乳化剂（乳清蛋白分离物（WPI）、酪蛋白酸钠和吐温 20）和增稠剂（黄原胶和果胶）对内水相（w）的油滴大小和产率的影响。与 WPI 和酪蛋白酸钠稳定的乳液相比，用吐温 20 稳定的乳液具有更小的油滴尺寸和更高的产率。内水相 w 的凝胶化使所有乳化剂的产率增加了 20%。当添加增稠剂时，外水相 w 的粘度增加会促进油滴破裂。这导致油滴更小，产率更低。与黄原胶相比，当使用果胶作为增稠剂时，产率观察到进一步降低。产率下降到接近零的值，表明在乳化过程中所有内水相 w 都丢失了。我们得出结论，亲水性乳化剂的类型、内水相的性质、连续相和分散相的粘度比以及增稠剂的类型都会影响双乳液的油滴大小和 w 相的产率。这项工作更好地理解了成分如何影响双乳液的性质，以及如何将其用于设计更复杂食品系统中的脂肪替代品双乳液。
