Thesis subject
Assessment of sensory satiety properties of foods and evaluation of their chemical-physical properties
The last decades, the incidence and prevalence of obesity is increasing reaching alarming levels in adults as well as in children. At this moment, more than 40% of the adult population in Western countries is overweight. Obesity is caused by an excess energy intake, which can be partly attributed to the availability of a large variety of highly palatable energy dense foods.
The excess energy intake by overweight and obese people is primarily related to a larger meal size, and not to a larger meal frequency. We hypothesize that the larger meal size of obese compared to lean people is likely to be caused by a lower sensitivity to sensory-specific and metabolic satiety. Due to a lower sensitivity to satiety, obese subjects take more bites before they stop eating than lean persons. This leads to a larger meal size, and therefore a higher energy intake. The issue of delayed meal termination is especially important with high fat foods, which are high in energy density, but inefficient in causing meal termination.
Sensory specific satiety depends on the flavour and texture attributes of foods. Some foods provide faster sensory specific satiety than others. For example, fish, meat and vegetables lead to sensory specific satiety more quickly than staple foods and many liquids. Dietary fat has a strong effect on both flavour release mechanisms and texture properties. The relationship between physical-chemical properties of foods and sensory specific satiety is not yet well understood. The understanding of this relationship will enable technologists in the food industry to develop foods with optimal satiety properties that help people to maintain a moderate energy intake.
The objective of the thesis is to develop a classification for foods based on their chemical-physical properties with high and low sensory satiety properties.
Possible experimental work involves development and execution of a questionnaire to study the sensory satiety performance (can you continue eating this food or are you quickly full/bored) for a large group of foods with distinctive properties. Based on these results the chemical-physical properties can be evaluated to identify potential food properties that affect satiety experience.
You will be supervised by both Pieternel Luning (Product design and quality management group) and Kees de Graaf (Nutrition and Epidemiology group)