title: Preservation of carbon dioxide clathrate hydrate in the presence of trehalose under freezer conditions.
abstract: To investigate the preservation of CO2 clathrate hydrate in the presence of sugar for the novel frozen dessert, mass fractions of CO2 clathrate hydrate in CO2 clathrate hydrate samples coexisting with trehalose were intermittently measured. The samples were prepared from trehalose aqueous solution with trehalose mass fractions of 0.05 and 0.10 at 3.0 MPa and 276.2 K. The samples having particle sizes of 1.0 mm and 5.6-8.0 mm were stored at 243.2 K and 253.2 K for three weeks under atmospheric pressure. The mass fractions of CO2 clathrate hydrate in the samples were 0.87-0.97 before the preservation, and CO2 clathrate hydrate still remained 0.56-0.76 in the mass fractions for 5.6-8.0 mm samples and 0.37-0.55 for 1.0 mm samples after the preservation. The preservation in the trehalose system was better than in the sucrose system and comparable to that in the pure CO2 clathrate hydrate system. This comparison indicates that trehalose is a more suitable sugar for the novel frozen carbonated dessert using CO2 clathrate hydrate than sucrose in terms of CO2 concentration in the dessert. It is inferred that existence of aqueous solution in the samples is a significant factor of the preservation of CO2 clathrate hydrate in the presence of sugar.
authors.affiliation: Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan.
authors.forename: Hironori D
authors.initials: HD
authors.lastname: Nagashima
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Takeya
authors.affiliation: Faculty of Engineering, Hokkaido University, N13 W8 Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Uchida
authors.affiliation: Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Ohmura
mesh_terms: D001274:Atmospheric Pressure; D002245:Carbon Dioxide; D005615:Freezing; D011309:Preservation, Biological; D014199:Trehalose
chemical_list: D002245:Carbon Dioxide; D014199:Trehalose