Publications

Content

  1. Doctoral Thesis
  2. Scientific Publications
  3. Other Publications
  4. Blog Posts
  5. Radio and Podcasts

1. Doctoral Thesis

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.

You can access the full text here.

2. Scientific Publications

In my experimental research, I worked with eye-tracking, virtual reality, and behavioural measures. Below, you find a list of my published research.

Food disgust sensitivity predicts disease-preventive behaviour beyond the food domain in the COVID-19 pandemic in Germany
In the fight against the COVID-19 pandemic, personal hygiene behaviours such as proper handwashing have gained significantly more attention and interpersonal contact is performed with great care. Disgust, as a disease-avoidance mechanism, can play an important role in the promotion of hygiene behaviour. We know from previous research that pathogen disgust can be a predictor of an individual’s behaviour in the pandemic. Given that the pandemic greatly affects our food and eating behaviour, the current study aims to add to the existing evidence and to complement it by investigating the role of food-specific disgust in the pandemic. For that, we conducted an online survey in Germany in April 2020, while the pandemic was spreading in Europe. A total of 519 participants completed the survey and provided information about their COVID-19-related attitudes and behaviours and about their food disgust sensitivity. The results show that food disgust sensitivity is an important predictor for an individual’s feelings, shopping behaviour, and disease-preventive behaviour related to the COVID-19 pandemic. Given that the success of political measures to fight the pandemic critically depends on the population to support and follow the proposed measures, a better understanding of the factors driving individual behaviour is key. Implications for pandemic management are discussed.

Comparison of two measures for assessing the volume of food waste in Swiss households
You can find an English translation of Figure 2 here.
The huge amount of food wasted at the consumer or household level has severe environmental and economic consequences. In the present work, we compared two self-report measures for the assessment of food waste quantities at the household level in Switzerland. Participants (N = 223) were asked to complete an online food waste questionnaire (FWQ), in which they were instructed to report the average amount of food waste produced in their households. In the second step, participants were asked to maintain a food waste diary (FWD) for 21 days. They were instructed to write down all food waste items, including their relative amounts, as well as the reason and method for their disposal. Using correlation and regression analyses, we found that the amount of food waste reported on the FWQ and in the FWD were highly correlated, revealing similar patterns in terms of their psychological predictors. In the context of the range of different methods available for the assessment of household food waste, our study has provided valuable insights into two of the most used self-report measures. Similarities between and limitations of the methods have also been discussed. This knowledge can be used to contextualise the available results, to design future studies, and ultimately, to help develop intervention strategies to reduce household food waste.

True colours: Advantages and challenges of virtual reality in a sensory science experiment on the influence of colour on flavour identification
The use of virtual reality (VR) in sensory science studies can offer new possibilities for experimental design. For instance, VR allows for the modification of visual product properties without changing the product composition. In a set of two augmented virtuality studies, we investigated whether the results we obtained in real-life (RL) settings were comparable to the results we obtained in a VR environment. In Study 1, we transferred an existing sensory science experiment to a VR setting. We invited 100 participants to taste two juices and a piece of cake. In the VR environment, participants saw the product either in its original colour or in a modified, product-atypical colour. After the product tasting, we asked them to identify the most dominant flavour. Participants had more difficulties identifying the flavour when the product was shown in a modified colour than when it was shown in its original colour. In Study 2, we added an RL control condition to facilitate a direct comparison between the two conditions and to verify our findings from Study 1. A chi-square test for association revealed no significant differences between the RL and VR conditions. We conclude that sensory studies can be successfully transferred to VR and obtain a generally similar pattern of results.

Does food disgust sensitivity influence eating behaviour? Experimental validation of the Food Disgust Scale
Tools that specifically measure food disgust sensitivity are scarce. This gap has been successfully filled with the recently developed eight-item version of the Food Disgust Scale (FDS short). In the present study, we tested the validity of this measure with three behavioural tasks that we designed. Participants (N = 108) filled in questionnaires before they tried three products as part of a behavioural task covered as tasting experiment. We presented these products with written scenarios, which aimed to induce disgust. For all three tasks, we found a significant correlation between the amount participants consumed and their FDS short score. In the first task, we presented participants with a meat product (r = −0.34, p < .001); in the second task, it was a banana juice (rs = −0.26, p < .01); and in the final task, we presented participants with an insect product (rs = −0.51, p < .001). A regression analysis confirmed that participants’ FDS short score acted as a significant predictor for eating behaviour in the meat (ß = −0.26, p < .05) and the chocolate task (odds ratio = 0.51), however, it did not reach statistical significance in the juice task (odds ratio = 0.66). In this paper, we present two important findings. First, we provide evidence for the influence of food disgust sensitivity on people’s eating behaviour as measured by the amount they consumed. Second, and more importantly, our data support the incremental validity of the FDS short as assessed through its correlation with three behavioural tasks and provide evidence for the suitability of self-report measures such as the FDS short.

The influence of disgust sensitivity on self-reported food hygiene behaviour
The present study aimed to investigate the relationship between people’s food disgust sensitivity and their food hygiene behaviour. We asked 1066 participants in Switzerland to complete an online survey. They provided information on how often they performed certain hygiene behaviours, how likely they would be to eat different food items after they had passed their expiration dates, and, using a specific scenario, how they would decide whether milk was safe to drink after they forgot to put it in the refrigerator overnight. We found that food disgust sensitivity was a significant predictor of participants’ edibility assessments and their reported frequencies of hygiene behaviour after controlling for age and sex. Our data suggested that food disgust was a strong predictor of food safety behaviour in the domestic kitchen. Learning more about people’s behaviour is crucial for the successful design of interventions to improve hygiene behaviour and the prevention of foodbourne diseases.

The relationship between disgust sensitivity and behaviour: A virtual reality study on food disgust
This study was the first to use virtual reality for disgust research and pursued two aims. First, we explored whether it was possible to induce disgust in a virtual environment. Second, we examined the relationship between food disgust sensitivity, presence (a psychological state of “being there”), and participants’ willingness to eat a food item after exposure to a virtual disgust cue. We asked 100 participants to eat chocolate and complete a tasting experiment within a virtual environment while wearing a head-mounted HTC Vive device. The control group (n = 50) saw a piece of chocolate appear in the virtual environment on a table in front of them before being asked to take and eat it. The disgust group (n = 50) saw a dog that walked across the table and stopped halfway to produce dog faeces that looked like a piece of chocolate. Subsequently, participants were asked to eat a real piece of chocolate. In both groups, participants were given the opportunity to refuse consumption. Participants in the experimental condition were more likely to refuse consumption than those in the control condition. Furthermore, in the experimental condition, we found that physical presence mediated the relationship between participants’ food disgust sensitivity and willingness to eat the chocolate. Our data suggested that virtual reality is a valid way to evoke disgust for the purposes of research and that people who are disgust sensitive have more difficulty ignoring virtual disgust cues than people who are less disgust sensitive.

Development and validation of the Food Disgust Picture Scale (Materials for the Food Disgust Picture Scale can be found here.)
The present set of studies developed and tested the Food Disgust Picture Scale (FDPS). This is a tool for the assessment of food disgust sensitivity that will measure disgust and predict possible reactions. This eight-picture tool can be used in complement to or as a replacement for currently available text-based measures. In an exploratory Study 1 (N = 57), we constructed a scale consisting of eight pictures. Most of them were taken from validated picture databases. They proved powerful in the assessment of food disgust sensitivity. Study 2 built on these results and refined the scale by substituting pictures from Study 1 with freely available images displaying similar content. The basic structure of the FDPS was then replicated in a bigger sample of Swiss adults (N = 538). Correlational analyses using the eight-item Food Disgust Scale (FDS short), the revised version of the Disgust Scale (DS-R), and the food neophobia scale (FNS) supported the convergent validity of the FDPS. In Study 3 (N = 226), we used a test-retest design to demonstrate the short-term stability of the FDPS. As a result of these studies, the present work provides a short and comprehensive measure of food disgust sensitivity. This novel approach of using pictures to induce a disgust response independently of language significantly facilitates intercultural research on disgust. The FDPS will further contribute to the understanding of food-related disgust and its impact on our food choices.

Cross-national comparison of the Food Disgust Picture Scale between Switzerland and China using confirmatory factor analysis (A short summary of the publication in the form of a video can be found here)
The Food Disgust Picture Scale (FDPS) is a newly developed picture tool that can be used to conduct cross-cultural assessments of food disgust sensitivity. It consists of eight food-related pictures, which participants rate according to the level of disgust they evoke. Due to the undeniable influence of culture on what individuals consider as disgusting, the FDPS’s validity across different food cultures is an interesting topic for research. The aim of the present study was to conduct a cross-national comparison of the FDPS in Switzerland and China. In total, 576 participants were recruited in China and 538 were recruited in Switzerland. The usability and construct validity of the FDPS were compared between the two countries using confirmatory factor analyses. In the current study we present two main findings. First, dropping one of the meat-related items and thereby reducing the eight-item FDPS to seven items improved the model fit in the Chinese (CFI = 0.98) and Swiss (CFI = 0.98) samples. Furthermore, it showed that the scale is a valid tool for the assessment of food disgust sensitivity in China. Second, using nested model comparisons, the present study has provided support for the model’s invariance across the two countries.

Cross-cultural validation of the FDS short in ten countries
The Food Disgust Picture Scale (FDPS) is a newly developed picture tool that can be used to conduct cross-cultural assessments of food disgust sensitivity. It consists of eight food-related pictures, which participants rate according to the level of disgust they evoke. Due to the undeniable influence of culture on what individuals consider as disgusting, the FDPS’s validity across different food cultures is an interesting topic for research. The aim of the present study was to conduct a cross-national comparison of the FDPS in Switzerland and China. In total, 576 participants were recruited in China and 538 were recruited in Switzerland. The usability and construct validity of the FDPS were compared between the two countries using confirmatory factor analyses. In the current study we present two main findings. First, dropping one of the meat-related items and thereby reducing the eight-item FDPS to seven items improved the model fit in the Chinese (CFI = 0.98) and Swiss (CFI = 0.98) samples. Furthermore, it showed that the scale is a valid tool for the assessment of food disgust sensitivity in China. Second, using nested model comparisons, the present study has provided support for the model’s invariance across the two countries.

A bitter taste in the mouth: The role of 6-n-propylthiouracil taster status and sex in food disgust sensitivity
We investigated the relationship between perceived bitterness, food disgust sensitivity, and sex. Participants completed the 8-item Food Disgust Scale and a 6-n-propylthiouracil (PROP) taster test and were categorised as PROP non-tasters, medium-tasters, or supertasters. An analysis of variance of between-subject factors sex and PROP taster status was conducted with disgust sensitivity as the dependent variable. We found a significant interaction of sex and PROP taster status on disgust sensitivity and an association between disgust sensitivity and PROP taster status in males but not in females. Our study provided new evidence on sex differences in food disgust and PROP taste sensitivity.

3. Other Publications

Die Zukunft jätet smart (Praxisartikel in der UFA Revue, Juni 2021)
Die Digitalisierung ist Teil der modernen Landwirtschaft. Dazu gehört auch der Freilandgemüsebau. Im Vergleich zu anderen Betriebszweigen sind digitale Technologien im Gemüsebau schon weit verbreitet. Wie sich das künftig entwickelt, und was dafür und dagegenspricht, zeigt eine Expertenbefragung.

9 Tipps für weniger Foodwaste beim Einkauf im Supermarkt (Interview mit Blick.ch, Januar 2021)
Rund ein Drittel aller produzierten Lebensmittel landen auf dem Müll. Diese Ressourcenverschwendung ist nicht nur für die Umwelt, sondern auch für den Geldbeutel ein Problem. Im Interview mit Blick gebe ich ein paar Tipps, was bereits beim Einkauf berücksichtigt werden kann, um Food Waste zu vermeiden.

9 Einkaufsfallen im Supermarkt (Interview mit Blick.ch, November 2020)
Wie kommt es, dass wir eigentlich nur ein Brot kaufen möchten, dann aber mit einer prall gefüllten Einkaufstasche wieder nach Hause zurückkehren? Dieser Frage bin ich in diesem Interview mit Blick nachgegangen.

Virtual Reality in der Sensorik-Forschung (Artikel im Alimenta, Juli 2020)
SVIAL-Mitglied Jeanine Ammann erforscht an der ETH Zürich in der Gruppe Consumer Behaviour die sensorische Wahrnehmung von Lebensmitteln. In den letzten Jahren entwickelte sich dabei die virtuelle Realität (VR) zu einem interessanten Forschungsmittel, das an der ETH schon in Studien zu Einkaufsverhalten und Ekel eingesetzt wurde. In zwei neuen Studien über den Einfluss der Farbe auf die Identifizierung von Geschmack, Lebensmittelqualität und -präferenz setzte Jeanine Ammann ebenfalls auf VR.

4. Blog Articles

Working with a computer and manoeuvring the depths of the virtual space can be challenging. I wrote a few blog articles for Projekt Neptun to help you overcome these challenges.

Password Managers
You keep forgetting your passwords, codes or credentials? Me too. That is why I started using a password manager. It saves you time and it makes your accounts much more secure.

How to set up your new computer
It might be exciting to get a new computer but it is also a challenge. There are a few things you should keep in mind.

Navigating the jungle – which laptop is best for me?
Overwhelmed by all the products available? Making sure you know your needs helps you find the perfect product.

How to help your computer survive an accident
It happens to all of us. Spilled liquid, dropped computers. Make sure you know what to do when an accident actually happens. It can save your computer’s life.

How I fell in love with my Lenovo ThinkPad X1 Yoga. A personal usage report.
Okay, I admit it, I bought my device from Projekt Neptun. Let me tell you all about it and explain to you, why I never regretted choosing it.

5. Radio and Podcasts

Richtiger Umgang mit Plastik
Für diese Radiosendung im Mai 2021 durfte ich Auskunft geben. Meine drei Ratschläge für den persönlichen Plastikkonsum:

  • Reduzieren. Viel Plastikabfall lässt sich vermeiden, indem man einfach verzichtet. Ich wähle beispielsweise spezifisch wenig verpacktes Gemüse von lokalen Produzenten.
  • Substituieren. Ich habe immer einen Stoffsack dabei. Dann kann ich an der Kasse bewusst auf den Plastiksack verzichten.
  • Wiederverwerten. Die Nutzung von PET-Flaschen ist nicht per se schlecht. Man sollte sich einfach bewusst sein, wieviele Ressourcen in der Verpackung stecken und sie nicht nach Einmalgebraucht achtlos wegwerfen. Eine PET-Flasche kann man gut ein paarmal wiederbefüllen und als Trinkflasche nutzen. Auch Stoffsäcke sind nicht per se gut, wenn man sie beispielsweise nur einmal benützt. Auch hier hilft ein bewusster, achtsamer Umgang mit den verfügbaren Ressourcen.