Same taste, different feeling – Taste perception differences between elderly and younger adults

1 December 2016 – Elderly and younger adults experience similar taste sensations, but enjoy tastes differently. This is one of the most evident outcomes from the research by Heleen Hoogeveen. The TiFN PhD fellow successfully defended her thesis on 30 November 2016, at the University of Groningen. Her work provides new leads for product development targeted at the elderly. 

Grandmother likes an extra tablespoon of sugar in her tea, and grandfather wants his potatoes with a heavy sprinkling of salt. In fact, compared to younger adults, many elderly prefer foods with intense tastes. Researchers tend to think that decreased taste sensation in the elderly is related to changes in taste enjoyment. “However, we observed that healthy older adults sense tastes similarly to young adults, but show a preference for sweet and salty tastes”, stresses Hoogeveen.“ This is probably because taste enjoyment is dependent on more factors than taste sensation alone.”

Neuronal processes
Searching for a better understanding of taste enjoyment, Hoogeveen investigated the neuronal processes taking place from the moment the product touches the tongue and stimulates the taste buds to the moment people say how much they did, or did not, like the taste. She and her colleagues were the first (via functional Magnetic Resonance Imaging (fMRI) to measure and compare brain activity in 39 healthy young adults (18-30 years of age) and 35 healthy elderly people (60 to 72 years of age), when tasting sweet, sour, salt and bitter at different concentrations.

In contrast to earlier findings, Hoogeveen found no activity differences in brain areas involved in taste sensations between the young adults and the elderly. This indicates that aging per se is not necessarily related to changes in taste sensation. However, brain areas involved in memory and emotions did show differences between the two age groups. “In elderly these areas showed higher activity, which might explain the differences in product appreciation between them and younger participants.”

Hoogeveen also investigated how the amount and composition of saliva affects taste processing in the brain. “Mucin concentration, as a proxy for saliva viscosity, was related to activity in a brain area that codes for taste intensity”, she says. “Perhaps this finding could impact salt and sugar reduction tools.”

Optimizing products
According to the PhD fellow, much food product development currently focuses on how foods can retard the aging process. “In addition to this focus on the nutritional value of food products, there should be just as much attention on optimizing the appreciation of products by the elderly”, she stresses. “Our work indicates the need for such research.”

Hoogeveen, who is looking for a position as a researcher in the food industry, experienced her time at TiFN as very inspiring. “It is challenging to translate fundamental outcomes into practical applications. In this project industry partners and scientists communicated concisely and effectively to bridge this gap, providing valuable outcomes for us all.”