Which characteristic of Natto: appearance, odor, or taste most affects preference for Natto.
BACKGROUND
In Japan, consumption of Natto, a fermented bean dish, is recommended because of its high quality protein, digestibility in the gut and its preventive effect on blood clot formation due to high vitamin K content. However, consumption of Natto in Kansai and the Chugoku area (the western part of Honshu) is less than that in the other areas of Japan probably because of a "food related cultural inhibition". In this study, we determined which characteristic of Natto (appearance, odor or taste) most affect subjects' perception of sensory attributes by observation of brain hemodynamics in relation to subjects' preference for Natto.


RESULTS
In this experiment, we defined each subject's changes in brain hemodynamics as (+) or (-) corresponding to an increase or a decrease in total hemoglobin concentration after stimuli compared to that before stimuli. As a result, there was no relation between preference for Natto and change in brain hemodynamics by the stimuli of "looking at" or "smelling", while there was a significant relationship between preference and stimulus of "ingestion"; (+) : (-) = 21:15 in the subjects of the "favorite" group and (+):(-) = 30:7 in the subjects of the "non-favorite" group (P = 0.034).


CONCLUSIONS
This result indicated that characteristic "taste" of Natto most affects preference for Natto.
Department of Food and Nutrition, Osaka City University, Sumiyoshi, Osaka, Japan.
Yuki
Y
Tsumura
Aki
A
Ohyane
Kuniko
K
Yamashita
Yoshiaki
Y
Sone
D001921:Brain / Q000098:blood supply / Q000502:physiology; D004435:Eating / Q000502:physiology*; D005260:Female; D005518:Food Preferences / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D012677:Sensation / Q000502:physiology*; D045730:Soy Foods; D055815:Young Adult