Interactions between texture and trigeminal stimulus in a liquid food system: effects on elderly consumers preferences.

Changes to the chemical senses of taste and smell that accompany ageing are widely believed to influence food preferences and consumption in the elderly. The possibility that interactions between the residual senses of texture and trigeminal perception can compensate for specific losses was explored using a complex liquid food system, soup. A consumer panel of twenty-four young people (20-35, mean age 27.7 +/- 3.95 years) and twenty-four elderly people (>65 years, mean age 73.6 +/- 5.78 years) were used for preference tests. Eight soups were prepared using a standardised recipe, with four variations in texture and two levels of trigeminal stimulus. The consumer panel preferences were measured using a nine point hedonic scale. The hedonic data was corrected for a scaling effect, and principle components analysis was completed on the normalised data of the two age cohorts. The preference decision of both age groups was in the direction of the lower level of trigeminal stimulation. Overall the older panel was less discriminating than the younger panel. However the older panel made an attempt to grade the different textures while the younger panel seemed to ignore the textural attribute in their preference decision. The older panel's preference decreased as the thickness of the soups increased across trigeminal levels. These results suggest that perhaps a judicious selection of a certain texture or mouthfeel combined with a preferred level of trigeminal irritation could boost elderly food enjoyment. Finally, a postal questionnaire was circulated to gain an insight in to the consumer's background and thus partially explain the motivation for their preferences.