2010 Volume 14 Issue 2 Pages 106-115
Food is crushed between the teeth, and/or between the tongue and palate or oral mucosa in the mouth and a bolus is thus formed with saliva. The present study aimed to determine how the food texture is affected by granularity and the moisture equivalent of food, and if food has a best texture for triggering swallowing.
The materials used in the present study were almond powder with three different granularities (1.4 mm, 600 mm and 500 mm in diameter) and sweet soy powder. The powders were mixed with artificial saliva, distilled water, 0.05% and 0.2% xanthan gum solution, to make an artificial food bolus. The effects of granularity and the moisture equivalent of materials on bolus texture were then investigated. Next, in human subjects, each material was mixed with saliva in the mouth until the subject reached the point of swallowing. Once the subject had decided to swallow, the materials were spat out and the moisture equivalent was measured.
Differences in the concentration of artificial saliva resulted in changes in the food texture. Although the materials showed different patterns of changes in food texture, the textures were similar among the samples when the subject decided to swallow at a certain point of moisture equivalent. Hardness, incohesiveness and adhesion for swallowing ranged between 9,400 and 11,900 N/m2, 0.48 and 0.66, and 1,000 and 3,300 J/m3, respectively. However, most subjects could not swallow almond powder of 1.4 mm diameter, even if mixed with saliva, and so this food texture was not plotted in the ranges above.
This study suggested that foods have a range of textures that are applicable for triggering swallowing.
