Date of Award

Summer 8-22-2019

Level of Access

Open-Access Thesis

Degree Name

Master of Science (MS)


Food Science and Human Nutrition


Mary Ellen Camire

Second Committee Member

Denise Skonberg

Third Committee Member

Jennifer Perry


Kokumi is a Japanese flavor profile that has been hailed as the sixth basic taste. Foods with kokumi are perceived as thick in consistency, rich in flavor, and well balanced with good mouthfeel. Kokumi can be found in many foods. Kokumi substances enhance mouthfulness and complexity and induce a long-lasting flavor. The calcium-sensing receptor (Ca-SR) is involved in the perception of kokumi. Kokumi compounds directly activate the Ca-SR. When activated, the Ca-SR can regulate satiety and modulate appetite, leading to the perception of a richer-tasting product and additionally, a more satisfying product. Moods and emotions also influence our food choices, and food choices can, in turn, influence moods and emotions. In this study, we examined the influence of kokumi substances on emotions. Tomato soup was chosen as the test food for kokumi enhancement because it is a familiar food product. Campbell’s® canned tomato soup was prepared according to the manufacturer’s instructions. Komi™ powder (Nikken Foods USA, Inc.) was added to half of the soup to make a concentration of 0.6% Komi on a weight basis. Instrumental color and viscosity measures were made on both types of soup (0 and 0.6% Komi) from triplicate batches. A series of sensory evaluation tests were performed. First, a triangle test was conducted to determine whether consumers could detect overall differences between the two kokumi concentrations. The sensory panelists were then given a sample of each soup coded with different three-digit numbers and asked to pick which sample they preferred. A third test investigated the acceptability of the two kokumi concentrations in tomato soup using a nine-point hedonic scale; panelists also completed demographic questions, the EsSense 25 questionnaire and the Dutch Eating Behavior Questionnaire restrained eating scale (DEBQ-R). Twenty of the 34 panelists in the triangle test correctly identified the different sample, which was significant at p ≤ 0.01. Equal numbers of panelists selected each kokumi level as preferred, so there was no significant difference in the paired reference test. One hundred consumers took part in the hedonic test, and 72% were female. Soup samples received mean hedonic scores of 7.0 and 6.8 for taste and overall liking respectively. The control soup had a higher liking for thickness than did the 0.6% kokumi sample (6.6 versus 6.1, p ≤ 0.05). Soup type did not have a significant effect on any emotion category. The median restrained eating score was 26, and panelists of both genders had mean scores similar to the median. These results could have resulted from the type of soup used in the study, the amount of kokumi, the length of the test, and panelist error. The test consisted of many questions and could have fatigued panelists. Further research is needed to determine optimal kokumi levels and foods for enhancement, and whether long-term consumption of foods with kokumi lead to great consumer satisfaction.