Murphy C
San Diego State University, CA 92182-0551.
Crit Rev Food Sci Nutr. 1993;33(1):3-15. doi: 10.1080/10408399309527607.
The elderly person's perception of foods and food flavor is affected by age-associated changes in the chemical senses (taste, smell, and trigeminal sensation). Both classic and modern psychophysical techniques have been applied to achieve some understanding of these changes. Taste threshold sensitivity declines with age; however, the magnitude of the decline and the degree to which taste qualities are differentially affected remains to be understood. Suprathreshold taste intensity perception is affected by age, but there is a differential effect of taste quality. Experiments with blended foods have indicated that both olfactory and taste deficits contribute to older people's difficulty with food identification. Experiments assessing threshold sensitivity, suprathreshold intensity, and suprathreshold identification have all demonstrated significant impairment in olfaction in old age. In fact, these effects are far greater than in the taste system. Patients with Alzheimer's disease show even greater olfactory deficits than normal elderly and the effect is related to the degree of dementia. We have ruled out nasal disease in these patients as the primary causes of olfactory insensitivity, because significant impairment remains when the influence of nasal airflow and nasal cytology has been removed statistically. Both normal elderly and patients with Alzheimer's disease show impairment in odor memory. Sensitivity to, familiarity with, and identifiability of the odors all play a role in odor memory performance. Flavor preference also changes over the lifespan. Older subjects, for instance, rate high concentration of sugar and salt as pleasanter than young subjects do. Multiple influences contribute to this phenomenon. Elderly persons and those of lower nutritional status have shown preferences for higher concentrations of casein hydrolysate than young persons and those of higher nutritional status, suggesting that dietary preference can be related to chemosensory cues. There are significant age-associated changes in chemosensory perception that have the potential to interact with dietary selection and nutrition in the elderly. A better understanding of these phenomena may promote health and well-being in the elderly.
老年人对食物和食物风味的感知会受到化学感官（味觉、嗅觉和三叉神经感觉）中与年龄相关变化的影响。经典和现代心理物理学技术都已被应用，以对这些变化有一定的了解。味觉阈值敏感性会随着年龄增长而下降；然而，下降的幅度以及味觉品质受到不同影响的程度仍有待了解。阈上味觉强度感知会受到年龄的影响，但味觉品质存在差异效应。对混合食物的实验表明，嗅觉和味觉缺陷都导致老年人在识别食物方面存在困难。评估阈值敏感性、阈上强度和阈上识别的实验均表明，老年人的嗅觉存在显著损伤。事实上，这些影响在嗅觉系统中比在味觉系统中要大得多。阿尔茨海默病患者的嗅觉缺陷比正常老年人更为严重，且这种影响与痴呆程度相关。我们已排除这些患者的鼻腔疾病是嗅觉不敏感的主要原因，因为在统计学上消除鼻气流和鼻细胞学的影响后，仍存在显著损伤。正常老年人和阿尔茨海默病患者在气味记忆方面均存在损伤。对气味的敏感性、熟悉程度和可识别性在气味记忆表现中均发挥作用。风味偏好也会在整个生命周期中发生变化。例如，老年受试者对高浓度糖和盐的评价比年轻受试者更为愉悦。多种因素导致了这一现象。与营养状况较低的老年人相比，营养状况较高的年轻人对酪蛋白水解物更高浓度的偏好更为明显，这表明饮食偏好可能与化学感官线索有关。化学感官感知中存在显著的与年龄相关的变化，这些变化有可能与老年人的饮食选择和营养相互作用。对这些现象的更好理解可能会促进老年人的健康和幸福。
