Comparison of the taste and the odor thresholds between the elderly and the young

2003 Fiscal Year Final Research Report Summary

• Project/Area Number: 14380043
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 食生活
• Research Institution: Ochanomizu University
• Principal Investigator: HATAE Keiko Ochanomizu University, Graduate School of Humanities and Sciences, Professor, 大学院・人間文化研究科, 教授 (50156337)
• Co-Investigator(Kenkyū-buntansha): TODA Sadako Takasaki University of Health and Welfare, Junior College, Professor, 短期大学部・生活学科, 教授 (90341792) ; KASAI Midori Ochanomizu University, Faculty of Human Life and Environmental Sciences, Associate Prof., 生活科学部, 助教授 (10262354)
• Project Period (FY): 2002 – 2003
• Keywords: 高齢者 / 味の閾値 / 塩味 / 甘味 / 酸味 / 官能検査 / においの閾値

Research Abstract

We often use odor and taste as a gauge to judge whether foods are edible or not edible. Reportedly the bitter taste is a signal of decomposition of protein, and sour taste is a signal of deterioration of starch. Also, odor or faint nasty smell is a key of deteriorated food. It is said that the elderly have lower taste and odor sensitivity than the young. However, whether the taste and odor sensitivity of the elderly is really decreased or how much decreased compared to the young is unclear. Thus, the taste thresholds and odor thresholds of 248 elderly and 127 young people were studied.
Eight different concentrations of NaCl solutions for salty taste, 7 of sucrose solutions for sweet taste, and 6 of citric acid solutions were prepared as taste test samples. Distilled water was used as a control. Both in the detection threshold and the recognition threshold of NaCl, and in the detection threshold of sucrose, were significantly (p<0.05> decreased in the elderly compared to the young. Odor test sample were 10 different concentrations of acetic acids, 11 of trimethylamine, and 13 of methylmercaptan. Distilled water was used as a control. As a result, the odor sensitivity of the elderly decreased. Moreover, 70% of the elderly did not realize that their odor sensitivity decreased.
Both taste and odor sensitivity decreased in the elderly.