Electromyography study of mastication of pickles by young and elderly people

Abstract

The chewing patterns of young and elderly people were analyzed by electromyography (EMG) and magnitude of chewing sounds during the process of eating pickles under normal conditions to examine differences in mastication by age and food characteristics. Four types of pickles were examined: takuan, pickled shallot, pickled ginger and pickled eggplant. The number of bursts and the duration of chewing were significantly higher in the elderly group compared to those in the young group. On the other hand, chewing cycle, EMG amplitude, muscle activity per chew and magnitude of chewing sound per chew were significantly higher in the young group compared to those in the elderly group. Next, chewing properties related to the differences among the pickles were investigated. Compared to pickled ginger and pickled eggplant, takuan and pickled shallot were judged to be more difficult to masticate based on their high EMG amplitudes, muscle activities per chew and magnitudes of chewing sound per chew. The time course results of muscle activity and chewing sound for takuan revealed dramatic variation in chewing throughout the course for the young group, but not for the elderly group. These findings suggest that young people adapt better to the texture of the pickles while eating.