Softer Meals That Impact the Life of the Elderly (SMILE) - Food Intake Study

Texture-modified diets support oral intake in older adults with chewing or swallowing difficulties, but conventional pureeing can reduce visual appeal and nutrient density. Phase 3 of the Softer Meals that Impact the Life of the Elderly (SMILE) study evaluates texture-modified soft meals designed to retain the recognisable appearance of familiar Asian foods.

This is a single-centre, single-group, two-period study conducted in a nursing home in Singapore. Each participant undergoes both the control and intervention conditions and therefore serves as their own comparator. The study comprises two consecutive seven-day periods. During the first period, participants receive the nursing home's existing texture-modified menu. During the second period, participants receive soft-meal versions of the corresponding menu items. The sequence is not randomised because the first period is intended to establish each participant's baseline intake under the nursing home's existing food-service conditions.

The intervention meals are prepared from menu items normally served by the nursing home. Individual meal components, including carbohydrate, protein and vegetable components, are processed separately. An enzyme gellant is incorporated into each processed food component to produce a soft and cohesive structure. The modified components are heated, transferred into food-grade silicone moulds resembling the original foods, allowed to set, unmoulded and plated. This preparation method is intended to retain the visual identity of individual meal components rather than presenting the meal as an indistinguishable puree.

The soft meals are prepared by nursing home kitchen chefs who have been trained by the research team in the use of the enzyme gellant and preparation method. Preparation is undertaken using the nursing home's existing kitchen facilities and equipment. The intervention is therefore designed to assess an approach that could potentially be incorporated into routine institutional food-service operations without specialised food-production equipment.

Before the intervention meals are served, the texture of the soft meals is verified by the nursing home's speech therapist as safe and appropriate for the participating residents. Meals are served through the nursing home's usual food-service arrangements, and nursing staff remain present during mealtimes as part of routine care.

Food intake is measured at breakfast, lunch and dinner on all seven days of each study period. Each food component is weighed separately before it is served using a weighing scale with two-decimal-place precision. After the participant has completed the meal, the remaining amount of each component is weighed using the same procedure. The amount consumed is calculated as the difference between the pre-meal serving weight and the post-meal leftover weight.

Photographs of each meal are taken before and after consumption to support validation of the weighed food records. The photographs document the served and remaining portions and provide a secondary record against which the food-weight measurements can be checked. The photographs are used for intake assessment and are not intended to replace direct weighing.

The nutritional intake associated with each measured food component is estimated by multiplying the amount consumed by the corresponding nutritional composition of that food item. This permits estimation of energy and macronutrient intake, including protein, carbohydrate and fat. Selected micronutrients, including calcium, iron and zinc, may also be estimated where suitable nutritional composition data are available.

Intake from thickened beverages, fruits and snacks outside the defined study meals is excluded from the food intake assessment, apart from afternoon tea where applicable under the study procedures. To minimise the influence of unrecorded intake, caregivers are informed not to provide participants with food from home or other external sources during the two study periods.

Using corresponding menu items across the two periods is intended to reduce variation arising from differences in the types of foods served. Conducting both periods within the same nursing home also allows meal preparation, food-service arrangements and mealtime support to remain as consistent as practicable. However, because the intervention always follows the baseline period, the study does not control for possible period or order effects.

The within-participant comparison is intended to determine whether changing the preparation and presentation of familiar texture-modified foods is associated with differences in measured oral intake and estimated nutrient intake. The study will provide preliminary evidence on the feasibility of producing visually recognisable texture-modified soft meals within a nursing home kitchen and implementing the meals through routine institutional food service. The findings will inform the design of future controlled studies and the development of culturally familiar texture-modified meals for older adults with chewing or swallowing difficulties.