Multi-scale structuring of the oil-water interface in fat crystal-stabilized emulsions

脂肪晶体稳定乳液中油水界面的多尺度结构

• 批准号: 217257-2013
• 负责人: Rousseau, Dérick
• 金额: $ 3.42万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=593965
• 关键词: Multi; scale; structuring; oil; water

Fat crystallization has a pronounced influence on the formation and quality attributes of food water-in-oil (W/O) emulsions such as butter, margarine, ice cream and low-fat chocolate, where water is dispersed as fine droplets within a continuous oil/fat network. In such products, 'Pickering' triacylglycerol (TG) crystals englobe dispersed water droplets and contribute to product texture and long-term stability against droplet coalescence and visual phase separation. Two recent discoveries in the Rousseau laboratory are paving the way to the systematic structuring of the physical properties of fat crystal-stabilized W/O emulsions at the molecular and microstructural length scales. We have recently shown that it is possible to 'coerce' otherwise surface-inactive fat crystals into crystallizing directly at the surface of dispersed water droplets by using interfacially-adsorbed liquid-state surfactants with a molecular structure compatible with the TGs. Secondly, shear-cooling of fat crystal-stabilized W/O emulsions within a confined environment induces fat crystal agglomeration into spheroidal, cocoon-like microstructures. Our research has led to development of a new form of Pickering-type stabilization where dispersed aqueous droplets are encapsulated within thick crystal shells. Currently in its infancy, a mechanistic understanding of these phenomena is necessary to fully understand and exploit these structured emulsions. Numerous research tools including Raman spectroscopy, rheology and microscopy will be used. My group also proposes the use of synchrotron X-ray diffraction to establish in-situ the true orientation of TGs and surfactants at the emulsion oil-water interface. Together these techniques will permit the dedicated design and construction of innovative structured Pickering-stabilized W/O emulsions at the molecular and microstructural length scales. The fundamental understanding gained will result in better emulsion stability and therefore increased shelf life for foods and other applications. As well, as W/O food emulsions are increasingly seen as vehicles for calorie reduction by food processors, this highly-feasible research will be a novel tool for the development of healthier processed foods.

脂肪结晶对食品油包水（W/O）乳液（如黄油、人造黄油、冰淇淋和低脂巧克力）的形成和质量属性具有显著影响，其中水作为细滴分散在连续的油/脂肪网络内。在这样的产品中，“皮克林”三酰甘油（TG）晶体包合分散的水滴，并有助于产品质地和长期稳定性，防止液滴聚结和可见的相分离。卢梭实验室最近的两项发现为脂肪晶体稳定的W/O乳液在分子和微观结构长度尺度上的物理性质的系统结构化铺平了道路。我们最近已经表明，它是可能的“胁迫”，否则表面活性的脂肪晶体直接在分散的水滴的表面结晶，通过使用界面吸附的液态表面活性剂与TG的分子结构兼容。第二，剪切冷却的脂肪晶体稳定的W/O乳液在一个封闭的环境中诱导脂肪晶体团聚成球状，茧状的微观结构。我们的研究导致了一种新形式的Pickering型稳定化的发展，其中分散的水液滴被封装在厚的晶体壳内。目前，在其婴儿期，这些现象的机械理解是必要的，以充分理解和利用这些结构化的乳液。许多研究工具，包括拉曼光谱，流变学和显微镜将被使用。我的小组还建议使用同步加速器X射线衍射来建立在原位的真正取向的TG和表面活性剂在乳化油-水界面。这些技术将允许在分子和微观结构长度尺度上专门设计和建造创新结构的Pickering稳定的W/O乳液。所获得的基本理解将导致更好的乳液稳定性，从而延长食品和其他应用的保质期。此外，随着W/O食品乳剂越来越多地被食品加工商视为减少热量的载体，这项高度可行的研究将成为开发更健康加工食品的新工具。