Invited speakers

Prof Mike Cates, University of Cambridge, UK

Title: Improving flowability of dense suspensions

Mike is a member of the Department of Applied Mathematics and Theoretical Physics. He heads the Soft Matter research group. His current research interests include: flow of colloids, polymers, emulsions, gels and other soft materials; shear-thickening and rheology in dense suspensions; dynamics of soft glasses; flow of liquid crystals; general theories of active matter; cellular locomotion; phase ordering in active and passive systems; statistical mechanics of active particles; and numerous other topics.

Abstract

The flow of very dense suspensions shows problematic features such as discontinous shear-thickening which can clog processing equipment. Such features are increasingly understood in terms of a stress-dependent contact friction between particles. This understanding explains the success of a common strategy for increasing flowability of suspensions at high solid content, which is to add ingredients (often listed misleadingly as 'emulsifiers') whose role is to reduce the friction by absorption onto the solid particles. It also suggests a second strategy that avoids such additives. This is to modify the process flow with a vibrational component that stops frictional contacts from building up.

Numerical simulations show this to be effective only if the vibration is transverse to the main flow rather than along it.

   
 

Dr Bill Frith, Unilever R&D, UK

Title: A physicists dream or nightmare? A brief overview of the microstructure of ice-cream, and how it is influenced by processing and storage

Dr Bill Frith is a physical scientist specialising in foods product technology. He has been working in industrial R&D since 1986, after completing his PhD he joined ICI in Runcorn, UK and spent seven years there. In 1993 he joined Unilever R&D at Colworth, and have been here ever since. People call him a Rheologist, but he sees himself as more of a general physical scientist, and he has experience across a broad range of topics including:

  • Reactivity in powder mixtures.
  • Pigment structure and scattering in coatings.
  • Computer simulation of particle packing.
  • Rheology of suspensions, emulsions, polymer solutions and gels.
  • Formation and properties of sheared gels.
  • Formation, stability and rheology of particle stabilised emulsions.
  • Self-assembly and gel formation of functionalised peptides and amino acids.
  • Ice-cream formulation, microstructure & properties.

Abstract

Ice cream is an immensely complex material that presents unique challenges in terms of manufacturing and distribution. It comprises many phases in varying degrees of disequilibrium, the main ones being ice, air, oil/fat and aqueous solution(s). The texture, flavour and quality of the ice-cream is critically dependent on the microstructure of these phases, most of which will evolve over time during manufacture and storage. In particular, the ice and air phases will ripen and disproportionate, leading to poor texture, and ultimately separation/collapse of the product. The process of microstructural evolution can be slowed by addition of stabilisers that structure the unfrozen phase, but a crucial role is also played by network formation of the fat and protein in solution. Networks are also crucial in the determination of the texture of the product, with the ice-crystal network being most prominent, providing the initial firmness, whilst the fat droplet network contributes to aspects such as a creamy mouth-feel.

In this talk I will give a brief overview of the microstructure of ice-cream and the various aspects that affect stability. I will then focus on the properties of the network forming components, in particular how fat and protein networks can form, and the roles they play.

   
 

Professor Tim Foster, University of Nottingham, UK

Title: Ingredient functionalities and how they are defined by, or define process steps in food 

Tim Foster graduated majoring in Plant Physiology before undertaking a PhD in the ‘Conformation and Properties of Xanthan Variants’. In 1992 he joined the Unilever R&D lab at Colworth House looking at the mobility of polymers in the plant cell wall. In 1994 he began to focus on the processing effects on the gelation of single and mixed hydrocolloid systems, and became the Biopolymers Group leader. In 1996 he worked on fat and gelatin replacement strategies in Spreads and Ice Cream products and in 1998 became the Spreads’ New Technology project leader. In 2003 he moved to the Vlaardingen laboratory in the Netherlands heading up a new department called ‘Delivery of Actives’, focussing on the improved health properties of foods and how flavour and bioactives are best delivered during the consumption and digestion of food. In 2005 became Unilever’s Senior Scientist in Food Structural Design, co-chairing the Unilever Food and Health Research Institute’s Research Strategy Group. His career to date has yielded 15 filed patents (currently 10 granted with two patents pending), the IChemE award for Innovation and Excellence in the Food and Drink sector in 2009 and numerous contributions to products reaching the supermarket shelves (e.g. Knorr Stockpot).

 

In 2007 he joined the University of Nottingham as Reader in Food Structure and in 2014 was promoted to Professor. He is currently Head of the Division of Food Sciences, the Director of the EPSRC Centre for Innovative Manufacturing in Food (2013-2018) and is Associate Editor of RSC’s Food & Function. The conversion of nutritious raw materials into food microstructures designed for optimal performance is his major driver.

 

Abstract

 

Food ingredients are traditionally refined into white powders of high functional specification. There is, however, a desire to use less-refined materials. Given these materials are from natural origin, there is variation in material properties at the molecular level, but when we consider less-refined samples, their natural variation will be both at the molecular and supramolecular level. This talk will cover some molecular thinking around the production of fluid gels, and some of the physics/engineering questions still remaining about the control of their mechanical properties. When considering the less-refined materials, then processes to ‘unpack’ the natural functional goodies within the supramolecular cell wall matrices can be considered. Additional concepts of functionalising these materials upon further processing will be introduced, such as control of the amorphous/crystalline ratio through ball milling and fibrillation through homogenisation. Upon further utilising these materials the use of fluid gels and functionalised natural materials will be processed using High Viscosity Jetting and Ink Jet Printing modes of ‘Additive Manufacturing’, indicating that new mesoscale structures can be built, by careful design of the input ingredients. Finally, a thought might be given to the next generation of fluid gels, which may come from the use of less-refined staring materials.

   
 

Dr Beccy Smith , Mondelez, UK

Title: (provisory) The Physics of Chocolate

Dr Beccy Smith leads the Modelling & Simulation group at Mondelez International. She joined the company when it was Cadbury, 16 years ago, following her PhD in Theoretical Condensed Matter Physics from the University of Birmingham. She is a keen promoter of science to children: having started up a company to create science & maths magazines for children, and presented a regular science slot on Blue Peter. Beccy is also very interested in food & sustainability: she lives with her three children & partner in a self-built eco-house on their smallholding with polytunnels, rare-breed sheep and poultry.
   
 

Mr Tim Kelf , Bühler UK Limited, UK

Title: The Physics of Optical Sorting in the Food Industry

Tim Kelf received his PhD in 2006 from the University of Southampton in the field of Plasmonics.  After post-doctoral positions working in ultra-fast nano-acoustics and bio-physics he move to Buhler-Sortex where he now heads up the sensor development group.  Tim’s main work relates to the investigation and prototyping of new optical technologies for both current and future machines.

Buhler Sortex, part of the Buhler group, is the world leader in the innovation and delivery of sorting solutions for global food and non-food processing industries. They are at the leading edge of technology in the design of high-speed optical systems, image processing, machine development and manufacturing. The company has won 6 Queen’s Awards for innovation and export achievement.

Abstract 

For 70 years sorting machines have been working quietly to clean and protect our food.  All bulk food, be it wheat, nuts, fruit etc., will have passed through at least one optical sorter before it reaches our homes, and this ensures that we don’t find stones in our rice or snails in our peas. 

A typical system, the size of a washing machine, is able to image over 50 million grains per hour whilst ensuring that grains with spots of size 0.5mm or larger are effectively removed.  To achieve such performance requires the input from a many of fields of research:  The flow of the product needs to be well understood and optimised to pass cleanly over the view.  The lighting and detection needs to be optimised for subtle colours.  Real time computation is required to process the gigabytes of data continuously generated by the cameras and to assess the colours and shapes of the grains; finally tiny air ejector need to precisely open and close at milli-second timescales to remove any objects assessed to be undesirable.

This talk will cover these core aspects of the sorting machine and describe of the physics involved in achieving the impressive performances we see today.

 

Lucinda Bruce-Gardyne, Genius Gluten Free, UK

More information will be here shortly.

Key dates

  • Early registration deadline:
    19 December 2017
  • Registration deadline:
    4 January 2018