title: Effect of Proteolytic Modification on Texture and Mastication of Heat-Treated Egg White Gels.
abstract: Raw egg white undergoes sol-gel transition by heat treatment, which changes it to an elastic gel. Here, protease treatment to render a new texture to heated egg white gel was applied. Protease-treated gels exhibited ductile flow without obvious rupture points. Transmission electron microscopy analysis showed that in protease-treated gels, protein aggregates were distributed more homogeneously compared with that observed in the untreated control, probably because ovalbumin was digested into small peptides as revealed by SDS-PAGE. The properties of the gel were evaluated by sensory tests and by measuring the movement of the masseter muscle, using surface electromyography. Results showed that maximum bite force and mastication duration were decreased for the protease-treated gels, which were evaluated as being softer, smoother, less elastic and better textured. Overall, our results indicate that protease-treated egg white gel has superior qualities and is easier to swallow than the untreated gel.
  
  
  
  In the food industry, the use of egg white is limited compared with that of egg yolk and whole eggs. In this study, we performed protease treatment to generate a new food material with smoother and softer texture compared with heat treated egg white. Our findings may expand the consumption of egg white, which can be consumed by people with mastication and swallowing disorders, and reduce the waste of egg white as a surplus product.
authors.affiliation: International College of Arts and Sciences Fukuoka Women's University 1-1-1 Kasumigaoka Higashi-ku Fukuoka 813-8529 Japan; Graduate School of Human Environment of Sciences Fukuoka Women's University 1-1-1 Kasumigaoka Higashi-kun Fukuoka 813-8529 Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Funaki
authors.affiliation: Faculty of Education Tokyo Gakugei University 4-1-1 Nukuikitamachi Koganeishi Tokyo 184-8501 Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Minami
authors.affiliation: Graduate School of Human Environment of Sciences Fukuoka Women's University 1-1-1 Kasumigaoka Higashi-ku Fukuoka 813-8529 Japan.
authors.forename: Sachie
authors.initials: S
authors.lastname: Abe
authors.affiliation: Graduate School of Agricultural and Life Sciences The University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan.
authors.forename: Reiko
authors.initials: R
authors.lastname: Ueda
authors.affiliation: International College of Arts and Sciences Fukuoka Women's University 1-1-1 Kasumigaoka Higashi-ku Fukuoka 813-8529 Japan.
authors.forename: Wakako
authors.initials: W
authors.lastname: Eto
authors.affiliation: Graduate School of Human Health Science University of Nagasaki 1-1-1 Manabino Nagayo-cho, Nishi-sonogi-gun Nagasaki 851-2195 Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kugino
authors.affiliation: Faculty of Wellness Studies Kwassui Women's University 1-50 Higashiyamate-machi Nagasaki 850-8515 Japan.
authors.forename: Mutsuko
authors.initials: M
authors.lastname: Kugino
authors.affiliation: Graduate School of Agricultural and Life Sciences The University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan; Project on Health and Anti-aging, Kanagawa Academy of Science and Technology, Life Science & Environment Research Center 4F C-4 3-25-13 Tono-machi Kawasaki-ku Kawasaki Kanagawa 210-0821 Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Abe
authors.affiliation: Graduate School of Information Science and Electrical Engineering Kyushu University 744 Motooka Nishi-ku Fukuoka 819-0395 Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Toko
authors.affiliation: Graduate School of Agricultural and Life Sciences The University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan.
authors.forename: Tomiko
authors.initials: T
authors.lastname: Asakura