Sensory Design of Foods for the Elderly
Good-Tasting and Easy to Swallow
June, 2008: Many elderly people have problems chewing and swallowing. Researchers at the Swedish Institute for Food and Biotechnology (SIK), a member of the European Sensory Network, used a variety of texture-modified meat and vegetable-based preparations to probe the problem of how foods can be formulated to meet the special needs of this particular target group.
Optimally, foods designed for the elderly should not only taste good and be healthy; they should also be easy to chew and swallow, since these two basic eating processes so often give older people problems. Spaces between the teeth, loose teeth, and badly fitting dentures often make it impossible to chew efficiently. But foods that are too soft, or too fluid can also lead to problems. The process of swallowing is complex and is easily influenced by physical changes, from lower production of saliva (a common side-effect of medicaments), to damage to the mucus membrane, on through nerve and muscle tissue injury.
Problems with swallowing not only take the enjoyment out of eating – they can also have dangerous consequences – such as acute difficulty in breathing or infection caused by food remains that could not be completely expelled from the respiratory tract.
The challenge for the food industry is to develop delectable food that can be easily ingested despite the consumers’ disabilities. The quality of taste often suffers when food is finely ground, grated, or pureed. These undesirable affects can be avoided through targeted food design – exactly how to go about this was the objective of Karin Wendin and the colleagues from the Swedish Institute for Food and Biotechnology (SIK).
First, food technologists systematically produced variations of meat and carrot preparations. They ground and pureed the source material to various degrees of consistency, and added differing amounts of egg yolk, cold or warm swelling starch, rapeseed oil, broth and water. A trained sensory panel subsequently made a detailed objective analysis of the sensorily perceptible properties of the variations.
Criteria Used by the Experts
Working independently from the panel, and with the impetus of focus group discussions, experts from a variety of fields, including dieticians, speech therapists, nurses, and chefs, put together a catalogue of criteria for optimal foods for patients suffering from swallowing disorders (dysphagia). The results: to be easy to swallow, products should have a soft, smooth, creamy mouth feel while giving no sticky, grainy, or greasy impression. Regarding these requirements the three products that appeared to be best suited for those suffering from dysphagia were chosen out of the test assortment.
It turned out that in the case of carrot preparations with texture gradients ranging from smooth to coarse samples, those with a somewhat coarser consistency were perceived as creamier and easier to swallow. All of the carrot products chosen by the experts contained a high portion of egg yolk and low levels of starch. However, there were differences in the amount of oil and the milling degree. For the meat products the experts chose the pureed preparations with high levels of egg yolk and varying levels of oil and starch.
Further important criteria for the optimal design of meals for those suffering from dysphagia were: the various meal components should be easy to identify separately, and should look appetising and taste good. They must have a coherent consistency in order to be easy to swallow. In addition, it is important for older people that the food has an intense taste, and high nutritional is very much desired.
Consumer Study of the Elderly
In a third step the researchers examined whether the decisions made with the help of sensory analysis and expert-led focus group discussions hit the mark, the people from the targeted consumer group were asked whether these decisions also met with their approval. To this purpose 208 men and women between the ages of 70 and 90 were interviewed. The participants were living on their own or in nursing homes. When questioned, one out of four complained of problems with swallowing, but only 20 percent had been diagnosed with dysphagia. Another 34 percent admitted to occasionally coughing during a meal, but were not aware that this could be symptomatic of a swallowing disorder. This indicates that older people are often not aware of these problems.
All of the products that were chosen by the experts met with the consumer’s approval. Both those consumers living in nursing homes and those living on their own positively rated the preparations as easy to chew and swallow and good-tasting.
The study could show that with the help of systematic sensory analysis of product variations and focus group discussions conducted by experts on dysphagia, it is possible to develop a product that fulfils the special needs of people who have difficulties with chewing and/or swallowing. Several basic findings from the study have already found their way to market; for example the food manufacturer Findus now has a product line targeted towards people with swallowing difficulties
Karin Wendin & Gunnar Hall
SIK- the Swedish Institute for Food and Biotechnology