State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, National Engineering Laboratory for Cereal Fermentation Technology, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, People's Republic of China.
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, National Engineering Laboratory for Cereal Fermentation Technology, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, People's Republic of China.
J Colloid Interface Sci. 2021 Apr;587:417-428. doi: 10.1016/j.jcis.2020.12.024. Epub 2020 Dec 13.
Lipid crystallization in O/W emulsions is essential to control the release of nutrients and to food structuring. While few information is involved in adjusting and controlling the performance of emulsions by adjusting oil phase crystallization behavior. We herein developed a novel strategy for designing lipid crystallization inside oil droplets by natural waxes to modify the O/W emulsion properties. Natural waxes, the bio-based and sustainable materials, displayed a high efficiency in modifying the crystallization behavior, droplet surface and shape, as well as the overall performance of emulsions. Specifically, waxes induced the formation of a new hydrocarbon chain distances of 3.70 and 4.15 Å and slightly decreased the lamellar distance (d) of the single crystallites, thus forming the large and rigid crystals in droplets. Interestingly, these large and rigid crystals in droplets tended to penetrate the interface film, forming the crystal bumps on the droplet surface and facilitating non-spherical shape transformation. The presence of rice bran wax (RW) and carnauba wax (CW) induced the droplet shape into ellipsoid and polyhedron shape, respectively. Furthermore, the uneven interface and non-spherical shape transformation promoted the crystalline droplet-droplet interaction, fabricating a three-dimensional network structure in O/W emulsions. Finally, both linear and nonlinear rheology strongly supported that waxes enhanced the crystalline droplet-droplet interaction and strengthened the network in O/W emulsions. Our findings give a clear insight into the effects of adding natural waxes into oil phase on the crystalline and physical behavior of emulsions, which provides a direction for the design and control of emulsion performance.
O/W 乳液中的脂质结晶对于控制营养物质的释放和食品结构至关重要。尽管通过调整油相结晶行为来调整和控制乳液性能的信息很少。我们在此开发了一种通过天然蜡在油滴内设计脂质结晶的新策略，以改变 O/W 乳液的性质。天然蜡是生物基和可持续的材料，在改变结晶行为、液滴表面和形状以及乳液的整体性能方面显示出很高的效率。具体来说，蜡诱导了新的烃链距离为 3.70 和 4.15 Å 的形成，并略微降低了单晶的层状距离（d），从而在液滴中形成了大而刚性的晶体。有趣的是，这些在液滴中的大而刚性的晶体倾向于穿透界面膜，在液滴表面形成晶体凸起，并促进非球形形状转变。米糠蜡（RW）和巴西棕榈蜡（CW）的存在分别使液滴形状呈椭圆形和多面体形。此外，不均匀的界面和非球形形状转变促进了结晶液滴-液滴相互作用，在 O/W 乳液中形成了三维网络结构。最后，线性和非线性流变学都强烈表明，蜡增强了结晶液滴-液滴相互作用并增强了 O/W 乳液中的网络。我们的研究结果清楚地了解了向油相中添加天然蜡对乳液结晶和物理行为的影响，为乳液性能的设计和控制提供了方向。
