Formation in food polymer/colloid systems

This research focuses on Food Materials Science, the functional behaviour of food components as related to their chemical, biochemical, physical and microstructural properties. The long-term goal is to increase our knowledge of the functional behavior of food polymers for the purpose of improving utilization and quality of our food resources. The short-term goals are to study (1) functional improvement of cationic antimicrobial peptides and (2) structure formation in polymer sols and gels. For the first objective, the antimicrobial peptide "protamine" is naturally occurring and active against a wide range of bacteria, but due to its high positive charge it binds non-specifically to many food proteins and is not suitable as a food ingredient. We are studying the chemical modification of protamine to improve its efficacy for food use. For the second objective, we intend to gain an understanding of structure formation in gelling polysaccharides by examining the properties of molecules, aggregates and gels while controlling factors such as temperature, pH and ionic environment that will give information on their functional behaviour and mechanisms of interaction. We are investigating their fractal nature, and applying Mathematical Modelling and Computer Simulation (MMCS) to gain more insight. Many gels are fractal and their underlying order can be described by the fractal dimension, D. D is characteristic of processes by which structure is built, so it will help us understand the mechanisms by which the gels are formed and allow us to control their characteristics. With MMCS, we create a mathematical model of a particular system that we want to study, such as polysaccharides in a solution containing ions. We write a computer code to represent this system and then carry out a numerical simulation of the system's dynamics and resulting structures. This enables us to carry out studies and measurements that might not be achievable in the lab, and can give insight into possible mechanisms by which structures are formed and/or to make predictions that will help guide laboratory experiments.