title: Textural evaluation of rice cake by chewing and swallowing measurements on human subjects.
abstract: The difficulty in masticating and swallowing rice cake was quantified. Healthy subjects ate pieces of rice cake (9 g and 3 g) and a modified product (9 g). We used electromyography to measure the activity of the jaw-closing and -opening muscles during chewing, as well as the suprahyoid muscle activity, laryngeal movement, and sound during swallowing. The smaller the rice cake, the shorter the mastication time, the fewer the number of chews, and the less the jaw-closing muscle activity. A modified rice cake product (9 g) was consumed with less mastication effort than the standard rice cake (9 g) and with the same effort as the standard (3 g). Both the sample amount and texture influenced mastication, although neither factor caused a significant difference in swallowing characteristics. These observations suggest that swallowing was induced when the bolus properties became suitable for swallowing, as healthy subjects could adjust their mastication technique according to the food amount and texture.
authors.affiliation: National Food Research Institute, Tsukuba, Ibaraki, Japan. kaoruk@affrc.go.jp
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kohyama
authors.forename: Hiroko
authors.initials: H
authors.lastname: Sawada
authors.forename: Miho
authors.initials: M
authors.lastname: Nonaka
authors.forename: Chiharu
authors.initials: C
authors.lastname: Kobori
authors.forename: Fumiyo
authors.initials: F
authors.lastname: Hayakawa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Sasaki
mesh_terms: D000328:Adult; D000368:Aged; D003679:Deglutition / Q000502:physiology*; D003680:Deglutition Disorders / Q000503:physiopathology; D004576:Electromyography; D005260:Female; D005502:Food; D006801:Humans; D007830:Larynx / Q000502:physiology; D008297:Male; D008406:Masseter Muscle / Q000502:physiology; D008409:Mastication / Q000502:physiology*; D012275:Oryza; D018401:Sample Size