食品乳液
案例
微凝胶在油水界面上的表现如何
以及它们如何响应压缩？扩大到乳液规模呢 ?
参考文献：Adsorption of microgels at an oil–water interface: correlation between packing and 2D elasticity. F. Pinaud; K. Geisel; P. Massé; B. Catargi, L. Isa; W. Richtering; V. Ravaine; V. Schmitt; Soft Matter, 2014, 10, 6963.
Probing oil-water interfaces laden with microgels evidences that these soft particles adsorb quasi irreversibly and that their structure adopts different packing states when the interface is compressed.
Moreover, experiments with a drop tensiometer (TRACKER™ by TECLIS) show that microgels adopt spontaneously a compressed morphology at an oil-water interface. The surface elasticity deduced from these measurements exhibits a maximum corresponding to the flattened conformation. Finally, the same spontaneous adsorption coverage is observed in emulsions, thus proving the usefulness of microgels in controlling the structure and the stability of emulsions.
TECLIS 产品： TRACKER™ 界面流变仪
关键词: microgels, oil-water interface, surface dilatational rheology, Langmuir trough, emulsion
用振荡滴技术和瞬时松弛技术获得的聚甘油聚蓖麻油酸酯在油/水界面的流变特性是否相等？
参考文献：Relaxation Processes of PGPR at the Water/Oil Interface Inferred by Oscillatory or Transient Viscoelasticity Measurement. S. Marze; Langmuir 2009, 25(20), 12066–12072; DOI: 10.1021/la9016849.
The rheological properties of PolyGlycerol PolyRicinoleate (PGPR) at an oil/water are probed with two different techniques: the oscillating drop technique using a drop tensiometer (TRACKER™) and the transient relaxation technique following and area step using the TRACKER™ as well. The data collected with this latter method are fitted afterwards with different models (Lucassen-van den Tempel, Maxwell model and a mixed model where both diffusion and rearrangements are considered).
Similar results are obtained with the oscillating drop technique and the transient relaxation technique especially at low frequencies.
TECLIS 产品： TRACKER™ 界面流变仪
关键词: PGPR, oil/water interface, interfacial rheology, emulsifier, oscillating drop technique, transient relaxation technique
在酸奶中加入木槿提取物微粒：
产生稳定系统的最佳离子凝胶法是什么？
参考文献：S. C. S. R. de Moura; G. N. Schettini; A. O. Garcia; D. A. Gallina; I. D. Alvim; M. D. Hubinger; Food and Bioprocess Technology; doi.org/10.1007/s11947-019-02308-9.
Encapsulation has demonstrated its value in the food and the pharmaceutical industries as it protects active components during transport and delivery. In this paper, the authors investigate the encapsulation of Hibiscus Extract (HE) by ionic gelation and the stability of these microparticles in a yogurt matrix. Two encapsulation methods are thus tested and compared: dripping and atomization.
But before looking into the final product, an important step towards the encapsulation of HE consists in generating an HE in oil emulsion. To do that, Polyglycerol polyricinoleate (PGPR, a nonionic emulsifier) is used. Thanks to interfacial tension measurements with a drop tensiometer (TRACKER™) between HE and rapeseed oil, the surfactant concentration that best promotes emulsification is identified. The effect of surfactant concentration on the microstructure of HE in rapeseed oil emulsion is also studied as shown in the figure.
TECLIS 产品： TRACKER™ 界面流变仪
关键词: Encapsulation, double emulsions, anthocyanins, hibiscus, ionic gelation, yogurt, interfacial tension, interfacial elasticity
植物蛋白和牛奶蛋白在水乳剂中的乳化性能和
稳定作用如何取决于浓度、pH值和温度？
参考文献：C. Amine; J. Dreher; T. Helgason; T. Tadros; Food Hydrocolloids 39 (2014) 180e186.
Through interfacial tension and interfacial elasticity measurements performed with a TRACKER™ tensiometer, the emulsifying properties and the stabilizing effect of plant (potato, soy and pea) and milk proteins (caseinate and whey) in MCT oil in water emulsions are probed under different conditions (concentration, pH and temperature). First, surface tensions are smaller at high pH values where protein molecules unfold. Second, the droplet size distribution is investigated, and a good correlation is thus found between emulsion formation and interfacial tension. Third, using the oscillating drop technique, the authors show a correlation (although not straightforward) between emulsion stability and film elasticity. Combined all together, these results highlight two competing effects: the formation of small droplets requires small interfacial tension and hence more proteins, however, a high protein concentration results in a decreased interfacial elasticity and, ultimately leads to less stability.
TECLIS 产品： TRACKER™ 界面流变仪
关键词: Oil in water emulsion, protein, interfacial tension, oscillating drop technique, Gibbs elasticity, stability
多层蛋白质/果胶薄膜的界面特性是什么？
参考文献：Colloids and Surfaces B: Biointerfaces Corstens, M. N.; Caltenco, L. A. O.; de Vries, R.; Schroën, K.; Berton-Carabin, C. C., 2017, 153, 199-207.
The multilayer deposit on a single vegetable oil in water droplet using an automated drop tensiometer was performed at pH 3. Under theses conditions, WPI is positively charged, and pectin is negatively charged. Between each deposit, aqueous phase was replaced by a fresh solution.
Surface tension recorded during the shell/shell structure building show that there are no supplementary surface tension decrease after the pectin addition indicating that pectin did not reach the interface and is probably electrostatically adsorbed onto WPI.
In a second time, authors study the activity of lipolytic components onto the shell/shell structure by reading the surface tension and the viscoelastic modulus of the drop model over time.
TECLIS 产品： TRACKER™ 界面流变仪 + 相转换选项
关键词: Multilayered emulsion, protein, pectin, drop tensiometery, bulk exchange
在植物乳蛋白混合物稳定的乳液中，
顺序吸收对油水界面的组成有何影响？
参考文献：Hinderink, Emma BA, et al. "Sequential adsorption and interfacial displacement in emulsions stabilized with plant-dairy protein blends." Journal of Colloid and Interface Science 583 (2020): 704-713.
Emulsions stabilized with plant-dairy protein blends exhibit complex interfacial structures. In this paper, protein displacement at oil-water interfaces is studied as a function of the sequence in which proteins are introduced. At the scale of a unique oil-water interface, surface tension and dilatational rheology experiments using a drop tensiometer with bulk-phase exchange (TRACKER™ by TECLIS) are performed. In the case of a whey-protein blend, the experiments showed that pea proteins adsorbed to pre-adsorbed whey proteins, leading to thick interfacial layers. The addition of whey proteins to a pea protein- or whey-pea protein blend-stabilized emulsion led to significant displacement of the pea proteins. The protein-protein interaction was hence identified as the driving force for this displacement.
TECLIS 产品： TRACKER™ 界面流变仪 + 相转换选项
关键词: emulsion, oil-water interface, pea protein, whey protein, bulk exchange, sequential adsorption
蛋白质和脂质的氧化是如何影响
油水界面上乳清蛋白层的粘弹性的？
参考文献：Protein and lipid oxidation affect the viscoelasticity of whey protein layers at the oil–water interface - Claire C. Berton-Carabin , Anja Schroder, Ana Rovalino-Cordova, Karin Schroën and Leonard Sagis - Eur. J. Lipid Sci. Technol. 2016.
Protein and lipid oxidation are prevailing issues that negatively affect the nutritional and sensory quality of food emulsions. It is probable that such oxidative modifications affect the functional properties of proteins. The aim of the study was to determine the influence of lipid and protein oxidation on the adsorption kinetics, surface activity, and dilatational rheology of protein films at the oil–water interface measured with the TRACKER™ drop tensiometer . Sunflower oil and whey proteins were used, as they are widely used in food formulations and can readily be subjected to oxidative modifications. The results obtained for oil with a high-intermediate level of oxidation (ca. 260 mmol CD per kg oil) show a drastic decrease of the elastic moduli of whey protein films, compared to freshly stripped oil. This indicates that the presence of surface-active lipid oxidation products dramatically decreased the elasticity of protein films.
TECLIS 产品： TRACKER™ 界面流变仪
关键词: interfacial tension, dilatational amplitude sweeps, dilatational elastic modulus, dilatational viscous modulus, Lissajous plots, Oxidative reactions, viscoelastic layers at the oil–water interface, food emulsion formulation / stability
蛋白质浓缩物的界面和发泡特性之间的关系
参考文献：Relationship between interfacial and foaming properties of a Porphyra dioica seaweed protein concentrate - Manuel Felix, Eva Puerta, Carlos Bengoechea, Cecilio Carrera-Sanchez - Journal of Food Engineering 291 (2021) 110238.
The main objective of this study was the assessment of interfacial properties of a seaweed protein concentrate (SWE) obtained from Porphyra dioica and how they are related to its foaming properties. For this purpose, surface properties were measured during protein adsorption (10,800 s) and after protein adsorption by two complementary techniques: the TRACKER™ drop tensiometer and an interfacial shear rheometer (DHR-3).
Thus, time sweep tests were performed during protein adsorption, while frequency step deformation tests after protein adsorption. Finally, these results were related to those obtained during foam formation and subsequent destabilization carried out by the FOAMSCAN™ foam analyzer.
TECLIS 产品： TRACKER™ 界面流变仪，FOAMSCAN™ 泡沫分析仪
关键词: Interfacial shear rheology, Protein adsorption, Foam capacity, Surface properties, saturation concentration, dilatational rheology, foam stability