02 - An Engineering Approach to Eating (Serafim Bakalis)

Design of effective functional foods requires an understanding of how food structure responds during all stages of digestion, in order to ensure effective delivery of “bioactive” food components and ensuing physiological and psychological responses involved, for example, in satiety control. The digestive process has traditionally been the domain of medical and nutritional science and is often focused on disease with little known about healthy functioning. An area that genuinely requires an interdisciplinary approach, much effort has been devoted in the last five years to bring diverse disciplines to bear on this subject, spanning human physiology, biochemistry, gut-to-brain signalling, physical chemistry and engineering.

In particular, engineering methods have been used in order to analyse the digestive systems to, understand fluid dynamics and the resulting effects on luminal events that determine the kinetics and pathways of digestion. In-vitro modelling has demonstrated that despite intestinal motility being very effective in mixing luminal contents during digestion, altering lumen viscosity by modifying food formulations can control the rate of starch hydrolysis and rates of absorption of glucose a surrogate for glycaemic response. An approach commonly used to achieve higher luminal viscosity includes addition of non-starch polysaccharides, which includes arabinoxylans, and important cereal food biopolymer which has potential to affect luminal viscosity and hence rates of absorption of cereal foods.