Dr. Peter Schuetz, Refreshment Discover Measurement Leader - Unilever R&D
X-ra(y)ted ice cream: Microstructural evolution in a multiphase soft solid
In Unilever Refreshment Discover we create a sustainable future for the ‘feel good’ experience in ice cream through science and technology.
The in mouth texture as part of the wider sensory experience of ice cream is determined by its microstructure where especially the shape, size and distribution of ice crystals in the matrix phase is of critical importance. These parameters are determined by formulation, processing and thermal history of the sample.
Here we used in situ X-ray tomography
to study the evolution of the ice cream structure during temperature oscillations in 3-D.
Julien Schmitt, Post Doctoral Research Associate, University of Bath
Formulation of cellulose-based hydrogels: probing the mechanisms of gelation via Small-Angle X-Ray Scattering and Rheology
Cellulose, as the most abundant natural polymer,1 is extensively studied in the formulation of new biodegradable materials,1 as it is biocompatible and environmentally friendly. It can be isolated from various sources (wood pulp, bacteria, tunicates and others) yielding variously shaped particles. Chemical modification allows dispersion of individualised fibrils. Specifically, oxidized cellulose nanofibrils (OCNF), obtained by TEMPO-mediated oxidation of plant or bacterial cellulose,2 present a high negative surface charge making them easy to disperse in water.3
Rheology studies demonstrate that OCNF suspensions have shear-thinning properties and form gels upon concentration (e.g. above 1.5 wt%), or in the presence of additives, such as salts (e.g. NaCl), surfactant or alcohol. Three TEM
experiments have been performed to describe the shape of the fibrils, found to be rigid cylinders with typically 5 nm cross sections and up to several hundred nm in length. SAXS
measurements of suspensions and gels provide a basis for studying the fibril-fibril interactions between OCNF upon concentration or in presence of additives and relate changes in interactions to the rheological behaviour. This leads to a better control of the formulation step to match the desired applications.
Dr Sin-Yuen Chang, Post-Doctoral Researcher, Diamond Light Source
X-ray Spectroscopy for Formulations
X-ray Spectroscopy is a useful and indispensable tool for gaining fundamental understanding of industrial processes, providing complementary and unique information compared with lab-based characterisation techniques. X-ray spectroscopy techniques have been used as a cost and time-efficient way to provide informed decisions to address manufacturing and formulation issues rather than applying a trial-and-error approach. This talk will focus on X-ray absorption
and photoelectron spectroscopy
. Molecular level information that can be obtained using these techniques include oxidation state, coordination number, ligand type, bond distance and coordination geometry. I will demonstrate some specific examples where X-ray spectroscopy has been used in the pharmaceutical and fuel additive industries.
Dr Sally Irvine, Industrial Liaison Scientist - Imaging, Diamond Light Source
Imaging techniques for formulations research
Imaging is one of the easiest synchrotron light techniques to conceptualise, due in large part to our familiarisation with medical x-ray imaging. Compared to hospital systems, synchrotron facilities can generate x-rays that are up to a trillion times brighter, from a much smaller spot size, which means we can acquire images at much faster speeds, and at higher resolution for smaller length-scales. We can also tune the x-ray energy or wavelength to improve the contrast, and play with distances to bring out the wave-like behaviour of the x-rays, which also yields additional contrast. Micro-tomography
is a 3D imaging technique which simply requires imaging during rotation of the sample. The computer reconstructed result gives us a volume representation of our sample which can then be virtually interrogated. It is ideal for visualising the sample microstructure, allowing us to observe and measure, e.g., cracks, pores, particle distributions, and even cells. Faster scans mean we can also image the sample over time through dynamic processes, giving us 4D in-situ
measurements. Whilst the range of scientific applications is almost unlimited, it is well-suited for answering key questions of industrial manufacturing and formulations issues affecting the product microstructure.
Claire Pizzey - Deputy Head of Industrial Liaison, Diamond Light Source
Probing the Microstructure of Formulations using Small Angle X-ray Scattering
The UK’s synchrotron facility, Diamond Light Source, produces X-ray, infra-red and ultraviolet beams of exceptional brightness. The combination of brilliant light and technological platforms is extensively used by the scientific community to undertake structural and chemical investigations of a wide variety of materials on very fast timescales. The industrial user programme
at Diamond is continuously growing with over 125 companies from 16 countries now making use of beamlines and offline facilities from formulation industries as diverse as consumer products, pharmaceuticals, foods and oil additives.
This talk will focus on the SAXS technique
for use in the study of the microstructure of soft matter systems. The technique can be applied to a wide variety of sample types including solutions, powders, suspensions, emulsions and gels and so it is highly relevant to probing physical and chemical behaviours of formulated products in order to enhance product performance. An overview of the SAXS technique will be presented along with illustrative case study examples.