Matching Items (3)
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- All Subjects: Food--Psychological aspects.
- All Subjects: Taste
- Genre: Doctoral Dissertation
- Creators: Capaldi Phillips, Elizabeth D
- Creators: Voytyuk, Mariya
- Creators: Wagner, Melissa C
Description
The unpleasant bitter taste found in many nutritious vegetables may deter their consumption. While bitterness suppression by prototypical tastants is well-studied in the chemical and pharmacological fields, mechanisms to reduce the bitterness of foods such as vegetables remain to be elucidated. Here tastants representing the taste primaries of salty and sweet were investigated as potential bitterness suppressors of three types of Brassicaceae vegetables. The secondary aim of these studies was to determine whether the bitter masking agents were differentially effective for bitter-sensitive and bitter-insensitive individuals. In all experiments, participants rated vegetables plain and with the addition of tastants. In Experiments 1-3, sucrose and NNS suppressed the bitterness of broccoli, Brussels sprouts, and cauliflower, whereas NaCl did not. Varying concentrations of NaCl and sucrose were introduced in Experiment 4 to assess the dose-dependency of the effects. While sucrose was a robust bitterness suppressor, NaCl suppressed bitterness only for participants who perceived the plain Brussels sprouts as highly bitter. Experiment 5, through the implementation of a rigorous control condition, determined that some but not all of this effect can be accounted for by regression to the mean. Individual variability in taste perception as determined by sampling of aqueous bitter, salty, and sweet solutions did not influence the degree of suppression by NaCl or sucrose. Consumption of vegetables is deterred by their bitter taste. Utilizing tastants to mask bitterness, a technique that preserves endogenous nutrients, can circumvent this issue. Sucrose is a robust bitter suppressor whereas the efficacy of NaCl is dependent upon bitterness perception of the plain vegetables.
ContributorsWilkie, Lynn Melissa (Author) / Capaldi Phillips, Elizabeth D (Thesis advisor) / Cohen, Adam (Committee member) / Johnston, Carol (Committee member) / Sanabria, Federico (Committee member) / Arizona State University (Publisher)
Created2014
Description
Given the continued increase in obesity rates in the United States, there has been growing research regarding factors related to obesity. Researchers have examined biological factors, such as set point theory, as well as various psychological factors such as motivation, self-efficacy, and eating styles. Taster-type, defined as how an individual experiences the perception of taste (particularly bitterness), is a recent area of research that has explored the potential relationship between this phenomenon and obesity. The current study examined whether taster-type impacted weight loss, along with secondary measures of BMI, waist circumference, and food neophobia, as well as taster-type’s impact on these measures over time. This study also examined the potential role of taster-type as a predictor of weight loss, independent of the psychological variables of motivation, self-efficacy, and eating styles. Ninety adult participants, consisting of 64 females and 19 males were recruited for this study. They were asked to diet for four weeks; 60 finished the full four weeks and completed psychosocial measures over two time periods. They were asked to record their food using an online food journal, attend weekly meetings for weigh-ins, and were given psychoeducational materials regarding factors affecting weight loss. The results indicated that taster-type was not a significant factor in BMI or waist circumference, but taster-type did interact with time to reveal that supertasters consistently lost weight across the four week dieting period while nontasters leveled off after Week 2. Additionally, both groups increased in food neophobia from the start of the dieting period to the end of Week 4. Consistent with previous research, motivation and self-efficacy predicted weight loss; however, taster-type did not increase the prediction of weight loss across the dieting period. This effect only occurred at Week 2. By Week 4, no psychosocial variables were significant predictors of weight loss.
ContributorsWagner, Melissa C (Author) / Robinson-Kurpius, Sharon (Thesis advisor) / Capaldi Phillips, Elizabeth (Committee member) / Homer, Judith (Committee member) / Arizona State University (Publisher)
Created2016
Description
Lay theories of healthy eating are a potentially important consideration for public health and nutrition efforts as perceptions and beliefs about “healthiness” are key determinants of dietary choices (Furst et al. 1996; Grunert, 2007). A rich body of social science literature has examined how people across cultures decide what counts as healthy eating, yet such work has focused mainly on what people think is good and bad to consume, overlooking another important aspect- how one eats. The ways one eats can include patterns and timing of meal intake, as well as mental and emotional states during eating (henceforth, “eating styles”). This dissertation aims to 1) examine whether beliefs on eating styles constitute a separate category of healthy eating perceptions, 2) describe American and Eastern European lay models of how both food characteristics and styles of eating shape health outcomes, and 2) investigate cross-cultural variation in the endorsement of eating styles as important for health in the United States and Eastern Europe. Aims 1 and 2 use pile sorts (n=48), in-person interviews (n=49), and online surveys (n=283) to elicit subjective perspectives on how different eating considerations impact health, and aim 3 involves two sets of questionnaires collected in the U.S. (n=50; n=42) and Eastern Europe (n=42; n=35) to test the hypothesis that levels of collectivism influence variation in endorsement of eating styles for health. Results demonstrate that “eating styles” is a separate category of beliefs in people’s models of healthy eating and individuals in both cultures perceive a variety of important health outcomes from how one eats- weight management, energy levels, digestive health, and overall feeling of wellbeing. These perceptions are not uniform, as participants held contrasting models of how styles of food consumption can influence weight control, and Eastern European respondents held additional views on how aspects of food timing can affect long-term health. Finally, results show that individual level of collectivism, not differences in nationality, accounts for variation in endorsement of eating styles for health. These results suggest that the holistic pattern of attention characteristic of the collectivist social orientation extends to the domain of diet.
ContributorsVoytyuk, Mariya (Author) / Hruschka, Daniel (Thesis advisor) / Slade, Alexandra (Committee member) / Bruening, Meredith (Committee member) / Arizona State University (Publisher)
Created2017