Oral processing in elderly: understanding eating capability to drive future food texture modifications

Ageing population suffer from increased risk of malnutrition which is a major determinant of accelerated loss of autonomy, adverse health outcomes and substantial health-care costs. Malnutrition is largely attributed to reduced nutrient intake which may be associated with several endogenous factors, such as decline of muscle mass, oral functions and coordination that can make the eating process difficult. From an exogenous viewpoint, nutritionally dense foods with limited innovations in food texture have been traditionally offered to elderly population that negatively affected pleasure of eating and ultimately, nutrient intake. Recent research has recognised that older adults within the same age group are not homogenous in terms of their preferences, nutritional needs, capabilities and impediments in skill-sets. Hence, a new term eating capability (EC) has been coined to describe various quantifiable endogenous factors in the well-coordinated eating process that may permit characterisation of the capabilities of elderly individuals in food handling and oral processing. This review covers current knowledge on EC focusing on parameters, such as hand and oro-facial muscle forces. Although limited in literature, EC score measured using a comprehensive toolkit has shown promise to predict eating difficulty perception and oral processing behaviour. Further systematic studies are required to explore relationships between individual/multiple constituents of EC and oral comfort. Such knowledge base is needed to underpin the creation of next generation personalised texture-modified foods for elderly population using sophisticated technologies, such as 3D printing to enhance eating pleasure, increase nutrient intake that will ultimately contribute to tackling malnutrition.