This project is an industrial CASE PhD studentship led by supervisors at the University of Leeds and the industrial supervisor at Unilever Colworth. It is an applied physics project combining work on advanced experimental techniques with development of new analysis approaches aimed to identify and understand the behaviour of food-related biopolymers.
For many food products, the aim of industrial R&D is to increase their sustainability, health and ethical credentials without compromising the user experience and cost. To achieve this, old rules based on existing ingredients may not hold any more and a thorough understanding of the relevant food matrices is necessary, not only on the macroscopic scale but on the microscopic and molecular scales. Foods are generally complex multi-phase structures, characterized by a wide range of length- and time-scales. This complexity means that advanced characterisation techniques and analysis approaches are needed to fully understand, and thus control, their behaviour.
This project focuses on the important food polymer Locust Bean Gum (LBG), which is derived from the seeds of the carob tree and is used in foods for its strong thickening, stabilizing and gel-forming properties. LBG is a neutral, linear polysaccharide which combines a mannose backbone with an irregular distribution of galactose side-chains where the different solubility of the backbone and side-chains lead to superstructures such as aggregates and ‘hyperentanglements’. LBG is often used in the presence of solutes such as polyols or sugars, which significantly modify the interactions and behaviour. For instance, it is well known that LBG solutions can form gels under suitable solvent conditions and in response to freeze-thaw cycles, where material structuring driven by ice growth can significantly modify the local LBG structure and rheology.
The project will combine a range of experimental techniques. Microscopy and scattering (light, x-ray and neutron) will be used to characterize the development of structure and dynamics across a wide range of length- and time-scales for LBG of varying chain characteristics and in solutions of varying solute composition. Both bulk rheology and microrheological techniques will be used to investigate how the local rheological response varies with LBG and solute composition and how this contributes to the bulk properties. The inter-relationship between ice growth, structuring and local rheology is of particular interest. The project will involve the development of new active microrheology techniques to address the difficult task of mapping out the link between local rheological properties, phase segregation and solution crystallization.
Continue with Facebook
