Maltodextrin promotes calcium caseinate fibre formation through air inclusion
Wang, Zhaojun ; Dekkers, Birgit L. ; Boom, Remko ; Goot, Atze Jan van der - \ 2019
Food Hydrocolloids 95 (2019). - ISSN 0268-005X - p. 143 - 151.
Air bubble - Anisotropy - Calcium caseinate - Fibrous appearance - Maltodextrin
Commercial calcium caseinate is available as spray-dried and roller-dried powder. Shearing a dense spray-dried calcium caseinate dispersion gives rise to a fibrous material, whereas shearing dense roller-dried calcium caseinate yields a layered material with only slight anisotropy in mechanical strength. The addition of a polysaccharide phase in a continuous protein phase may lead to formation of fibrous structures after shearing, which is hypothesized to be a result of the elongation and orientation of the dispersed polysaccharide domains. We report the effect of the addition of maltodextrin to roller-dried calcium caseinate on structure formation. The strength of the material increased with the addition of maltodextrin, which is partly caused by the withdrawal of water from the caseinate phase towards the maltodextrin phase, leading to a higher local caseinate concentration. The anisotropy of fracture stress and fracture strain were enhanced with up to 5 wt% maltodextrin. The effect of maltodextrin on the mechanical anisotropy and fibrous appearance could be ascribed to the greater air incorporation as a result of the presence of maltodextrin.
Air bubbles in calcium caseinate fibrous material enhances anisotropy
Wang, Zhaojun ; Tian, Bei ; Boom, Remko ; Goot, Atze Jan van der - \ 2019
Food Hydrocolloids 87 (2019). - ISSN 0268-005X - p. 497 - 505.
Air bubble - Anisotropy - Fibrous material - Mechanical property - Microstructure
Dense calcium caseinate dispersions can be transformed into hierarchically fibrous structures by shear deformation. This transformation can be attributed to the intrinsic properties of calcium caseinate. Depending on the dispersion preparation method, a certain amount of air gets entrapped in the sheared protein matrix. Although anisotropy is obtained in the absence of entrapped air, the fibrous appearance and mechanical anisotropy of the calcium caseinate materials are more pronounced with dispersed air present. The presence of air induces the protein fibers to be arranged in microscale bundles, and the fracture strain and stress in the parallel direction are larger compared with the material without air. The effects can be understood from the alignment of the fibers in the parallel direction, providing strain energy dissipation. This study shows that creation of anisotropy is the result of interactions between multiple phases.
Structuring processes for meat analogues
Dekkers, Birgit L. ; Boom, Remko M. ; Goot, Atze Jan van der - \ 2018
Trends in Food Science and Technology 81 (2018). - ISSN 0924-2244 - p. 25 - 36.
Anisotropy - Fibrous products - Meat analogues - Plant protein - Structuring
Background: Animal-derived protein foods, such as meat, have a large impact on the environment. Meat analogues are products that replace meat in its functionality, i.e. have similar product properties and sensory attributes, which is achieved by the fibrous nature of those products. Scope and approach: The techniques used to make fibrous products that mimic muscle meats are outlined and categorized based on their approach. The bottom-up approach refers to assembly of structural elements that are combined. The top-down approach refers to structuring of biopolymer blends using an overall force field. The strengths and weaknesses of these approaches are discussed in terms of ingredient and equipment use, (achievable) product resemblance, robustness, scalability, and resource efficiency. To enlarge the theoretical framework, the techniques with the top-down strategy are further contextualized by relating to structure formation processes of materials with other applications, and the methods to analyse the fibrous structures are further outlined. Key findings and conclusions: Techniques that follow the bottom-up strategy have the potential to resemble the structure of meat most closely, by structuring the proteins hierarchically through assembly of individual structural components. The top-down strategy is better scalable, is more efficient in its use of resources, but can only create the desired structure on larger length scales. Significant progress has been made on the methods to analyse structured products from the last category. Most analysis methods focussed on the (micro)structural anisotropy of the fibrous products, however there is also a need for methods that allow in situ analysis of the evolution of the structure during processing.
Single Molecule 3D Orientation in Time and Space : A 6D Dynamic Study on Fluorescently Labeled Lipid Membranes
Börner, Richard ; Ehrlich, Nicky ; Hohlbein, Johannes ; Hübner, Christian G. - \ 2016
Journal of Fluorescence 26 (2016)3. - ISSN 1053-0509 - p. 963 - 975.
3D dipole orientation - Anisotropy - Confocal microscopy - FCS - Fluorescence microscopy - GUV - Single molecule
Interactions between single molecules profoundly depend on their mutual three-dimensional orientation. Recently, we demonstrated a technique that allows for orientation determination of single dipole emitters using a polarization-resolved distribution of fluorescence into several detection channels. As the method is based on the detection of single photons, it additionally allows for performing fluorescence correlation spectroscopy (FCS) as well as dynamical anisotropy measurements thereby providing access to fast orientational dynamics down to the nanosecond time scale. The 3D orientation is particularly interesting in non-isotropic environments such as lipid membranes, which are of great importance in biology. We used giant unilamellar vesicles (GUVs) labeled with fluorescent dyes down to a single molecule concentration as a model system for both, assessing the robustness of the orientation determination at different timescales and quantifying the associated errors. The vesicles provide a well-defined spherical surface, such that the use of fluorescent lipid dyes (DiO) allows to establish a a wide range of dipole orientations experimentally. To complement our experimental data, we performed Monte Carlo simulations of the rotational dynamics of dipoles incorporated into lipid membranes. Our study offers a comprehensive view on the dye orientation behavior in a lipid membrane with high spatiotemporal resolution representing a six-dimensional fluorescence detection approach.