Matching Items (2)
Filtering by

Clear all filters

152889-Thumbnail Image.png

Individual differences in the efficacy of sodium chloride and sucrose as bitterness suppressors of brassicaceae vegetables

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…

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
154431-Thumbnail Image.png

Assessing the impact of oral vitamin B12 supplementation on vibration sensitivity, dexterity, and balance in young adult vegetarians and vegans

Description
Vitamin B12, found only in animal products, is a water-soluble vitamin important for DNA methylation, purine and pyrimidine synthesis, and the myelination of nerves. Symptoms of vitamin B12 deficiency include anemia, gait disturbances, altered vibration proprioception, impaired vision, psychosis, depression, dementia-like illness, and ultimately death. Because vegetarians and…

Vitamin B12, found only in animal products, is a water-soluble vitamin important for DNA methylation, purine and pyrimidine synthesis, and the myelination of nerves. Symptoms of vitamin B12 deficiency include anemia, gait disturbances, altered vibration proprioception, impaired vision, psychosis, depression, dementia-like illness, and ultimately death. Because vegetarians and vegans consume fewer animal products in their diet than omnivores, they are inherently more at risk for developing these symptoms of vitamin B12 deficiency. Thus, the purpose of this study is to examine the correlation between nervous system markers (balance, dexterity, and vibration sensitivity) and markers of vitamin B12 nutriture (serum B12 and serum holo-transcobalamin II) in a cross-sectional study (n=38). In addition, the impact of daily oral vitamin B12 supplementation on these markers in an 8-week randomized controlled trial was also examined (n=18). The results of the cross-sectional study revealed a moderate correlation (R=-0.351, p=0.031) between serum B12 and left-hand functional dexterity. The results of the intervention study revealed no significant time*group interactions for markers of nervous system functions and biochemical values (after the removal of outliers). In addition, the time*group interaction appeared to be larger for those individuals with a baseline serum B12 of less than 303 pmol/L. These results suggest that vitamin B12 supplementation may have a more pronounced effect on those individuals who are in a state of vitamin B12 depletion (<303 pmol/L serum concentration). In addition, the results also suggest that 8 weeks of oral supplementation is not a long enough period to create significant clinical change, and it is likely that improvements in neurological measures would require long-term supplementation.
ContributorsArnold, Taylor (Author) / Johnston, Carol (Thesis advisor) / Whisner, Corrie (Committee member) / Ohri-Vachaspati, Punam (Committee member) / Lee, Chong (Committee member) / Aleck, Kyrieckos (Committee member) / Arizona State University (Publisher)
Created2016