Abstract
Rice gruel samples were prepared by adding to rice gruel a commercial gelling agent whose main ingredients were konjak glucomannan, a kind of dietary fiber hydrocolloid, and a polysaccharide thickener. We examined the correlation between the physical properties of the samples and ease of eating by a sensory evaluation and electromyographic measurement of the musculature during mastication and swallowing. The sensory evaluation showed that adding the gelling agent to rice gruel resulted in the perception of less stickiness and better cohesion in the oral sensation. Cooling of the samples with time significantly increased the hardness and rupture load for a single grain of rice in the gruel. This cooling made mastication of the sample more difficult, and also extended the muscle activity duration of the supra-hyoid musculature that is used for conveying the food bolus from the oral cavity to the pharynx.
