• Admin
    UC Research Repository
    View Item 
       
    • UC Home
    • Library
    • UC Research Repository
    • College of Engineering
    • Engineering: Theses and Dissertations
    • View Item
       
    • UC Home
    • Library
    • UC Research Repository
    • College of Engineering
    • Engineering: Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of the RepositoryCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    Statistics

    View Usage Statistics

    Physical properties of simple and complex sugar systems.

    Thumbnail
    View/Open
    Subbiah, Balaji_Final PhD Thesis.pdf (2.173Mb)
    Author
    Subbiah, Balaji
    Date
    2018
    Permanent Link
    http://hdl.handle.net/10092/16530
    Thesis Discipline
    Chemical Engineering
    Degree Grantor
    University of Canterbury
    Degree Level
    Doctoral
    Degree Name
    Doctor of Philosophy

    Honey, maple syrup and sugars during refining are examples of a complex solutions of concentrated sugars and other solutes. The physical properties of such systems are required for the design and optimization of processes and for the understanding of the behaviour of the final product. Literature shows limited data and even less rigorous analysis of the physical properties of concentrated sugar solutions. A fundamental thermodynamic approach provides an effective basis for the analysis and prediction of these properties. The main focus of this study was to consolidate physical property data for binary sugar systems, analyse the data using existing models, and propose newer models and equations to predict the physical properties of complex sugar solutions like honey.

    In order to approach this, the physical properties density, viscosity, electrical conductivity, refractive index, mutarotation and water activity of binary solutions and sugar mixtures ranging from invert sugar solutions to model honey solutions with acid and salt were measured. Models that have been applied to sugar systems were reviewed. An equation for density based on the apparent densities of sugars in solution was validated. A viscosity equation that was extended from previous work with concentrated milk systems, was found to be very effective over the full concentration range of complex sugar solutions. Effects of viscosity on the electrical conductivity of sugar systems were analysed and a model was proposed for electrical conductivity in sugar systems. Hydration theory based on water activity measurements was applied to binary sugar systems and extended to model honey systems. Mixing theories were applied to the calculation of refractive index of solutions and also used as a tool to confirm the solid mass fraction in solutions.

    The effect of mutarotation of sugars in viscous sugar solutions was studied using a new NMR technique that was validated using polarimetric measurements. In this study it was found that the mutarotation of glucose was not affected by the viscosity of the solution.

    Past and new data and resulting equations provide a solid basis for future modelling and simulation of crystallization in these systems.

    Collections
    • Engineering: Theses and Dissertations [2264]
    Rights
    https://canterbury.libguides.com/rights/theses

    UC Research Repository
    University Library
    University of Canterbury
    Private Bag 4800
    Christchurch 8140

    Phone
    364 2987 ext 8718

    Email
    ucresearchrepository@canterbury.ac.nz

    Follow us
    FacebookTwitterYoutube

    © University of Canterbury Library
    Send Feedback | Contact Us