INDIVIDUAL DIFFERENCES IN AFFECTIVE RESPONSES TO SOURNESS

Open Access
Author:
Parlow, Bryna Helaine
Area of Honors:
Food Science
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • John Hayes, Thesis Supervisor
  • John E Hayes, Honors Advisor
  • Helene Hopfer, Faculty Reader
Keywords:
  • sourness
  • sensory
  • food science
  • perception
Abstract:
Genetic variances affecting individuals’ perceptions of stimuli, including twin studies and more recently molecular genetics, has been documented for many years. Multiple studies with sweetened solutions have shown that people fall into one of several patterns of hedonic responses in respect to the concentration of the sample given. These differences would be obscured if the whole population’s responses were averaged and not split by response group. This experiment was conducted to see if these types of patterns observed in sweetness can also be observed in regards to sour tasting solutions. In hopes to replicate previous work on sour hedonic responses, adults (N=102) tasted a series of six concentrations of citric acid solutions and rated them for sour intensity as well as liking. A systematic algorithm, previously implemented in the R statistical language, was used to segment the participants into five distinct groups, linear positive, linear negative, flat, and two distinct inverted-U curves, to confirm prior work. Prior work was extended by determining if these groupings might explain differences in liking for a variety of sour foods sampled in the laboratory. No significant differences were observed between the curve type and hedonic ratings for the foods. However, group mean for each curve type supported the notion that the population is segmented in response to sour stimuli.