Masticatory difficulty and mechanical characteristics of kelp snacks

Tensile test, sensory evaluation, electromyography and masticatory pressure measurement of kelp snack were carried out in order to clarify the characteristics as a functional food for mastication training. Though no difference can be detected in breaking stress of kelp samples used in the present study, breaking force is different according to their thickness. In the sensory evaluation, it was judged that the samples with a high breaking force were difficult to masticate. In the electromyography, the sample judged difficult to masticate showed long mastication time, many number of chewing strokes, and high total muscle activity needed until swallowing. In the meantime, there was no significant difference among the samples in masticatory force, contact area, and masticatory pressure in the first chew. It is considered that mechanical characteristics of the samples with higher breaking stress than masticatory pressure influence total masticatory behavior but don't affect the first chew of human.