Designing foods for an increasingly elderly population: a challenge of the XXI century

Providing food for the elderly, particularly the frail ones, requires an awareness of physiological, psychological, nutritional, and socioeconomic conditions. Thus, designing foods for the elderly will not only need the attention of products' properties and behavior inside the body (internal factors) but also to the context in which foods are provided and consumed (external factors). In this article, we review and discuss how the design of liquids and soft meals is conditioned by impaired oral processing and swallowing of the food bolus, diminished digestion and nutrient absorption capacity, and adverse microbiota functionality. Major technologies used to produce thickened liquids and texture-modified foods are presented. A conceptual framework for the rational design of foods for the elderly is proposed based on a multidisciplinary knowledge toolbox, and a multiscale food structuring/assembling approach. We emphasize that feeding older people is a multifactorial problem that demands the interplay of several disciplines and transdisciplinary approaches.