Assessment and Implications of Food Disgust: The Influence of Food Disgust Sensitivity on Food Choice, Risk Avoidance, and Hygiene Behaviour

The emotion of disgust has a protective function over both mind and body. The present thesis has focused on food disgust, that is, the rejection of food, and pursued three aims. First, the present work has found, developed, and tested reliable measures of food disgust sensitivity. Second, it has identified individual factors that influence food disgust sensitivity, and third, it has investigated and discussed the implications of food disgust sensitivity for human behaviour, including food choice and hygiene. The thesis has used behavioural measures, tasting experiments, and online surveys to pursue these goals. It has confirmed the validity of an existing self-report measure of food disgust using behavioural measures and developed and tested a new, picture-based tool. With this tool, the cross-cultural validity of the construct of food disgust was demonstrated in China and Switzerland. Throughout the present work, findings showed that females have higher food disgust sensitivity than males. Finally, the thesis has demonstrated that food disgust has important implications for food-related behaviours such as food wastage, hygiene behaviour, and food choice. The present work has provided new evidence and interpretations of how disgust sensitivity shapes food choice. Specifically, it has reported a relationship between bitter taste and disgust sensitivity in males but not in females, according to the findings of a tasting experiment. This contrasts with the results of previous studies, and the current work has discussed possible explanations for this. Moreover, this thesis has used virtual reality as a novel approach to induce disgust during research. The findings showed that individuals high in food disgust sensitivity have more trouble distancing themselves from virtual disgust elicitors than individuals low in disgust sensitivity. Finally, the thesis has reported findings from an online survey, which indicated that individuals high in food disgust sensitivity use more restrictive assessment criteria when deciding whether a food item can be consumed than those low in food disgust sensitivity. They have also reported higher frequencies of food hygiene behaviour than participants with low disgust sensitivity. In sum, the present work has validated an existing self-report measure of food disgust and developed a new picture-based tool, which could be a promising measure for research with children or when pictures might be preferred to text. The current work has investigated the influence of sex and culture on disgust sensitivity and assessed how disgust shapes food choice and hygiene behaviour. Above all, it has added to current understandings of disgust and its implications. This is crucial for both researchers and the food industry. The knowledge herein can be used to study and treat eating disorders; help develop interventions to increase people’s acceptance of novel foods, such as insects or artificial meat; to design an action plan to promote food hygiene; and to implement measures to reduce food waste.