title: Effects of High Hydrostatic Pressure on Water Absorption of Adzuki Beans.
abstract: The effect of high hydrostatic pressure (HHP) treatment on dried soybean, adzuki bean, and kintoki kidney bean, which are low-moisture-content cellular biological materials, was investigated from the viewpoint of water absorption. The samples were vacuum-packed with distilled water and pressurized at 200 MPa and 25 °C for 10 min. After the HHP treatment, time courses of the moisture contents of the samples were measured, and the dimensionless moisture contents were estimated. Water absorption in the case of soybean could be fitted well by a simple water diffusion model. High pressures were found to have negligible effects on water absorption into the cotyledon of soybean and kintoki kidney bean. A non-linear least square method based on the Weibull equation was applied for the adzuki beans, and the effective water diffusion coefficient was found to increase significantly from 8.6 × 10-13to 6.7 × 10-10m²/s after HHP treatment. Approximately 30% of the testa of the adzuki bean was damaged upon HHP treatment, which was comparable to the surface area of the testa in the partially peeled adzuki bean sample. Thus, HHP was confirmed to promote mass transfer to the cotyledon of legumes with a tight testa.
authors.affiliation: Faculty of Education, Saitama University, 255 Shimo Okubo, Sakura-ku, Saitama 338-8570, Japan. shigeakiu@mail.saitama-u.ac.jp.
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Ueno
authors.affiliation: Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan. shige@nupals.ac.jp.
authors.forename: Toru
authors.initials: T
authors.lastname: Shigematsu
authors.affiliation: Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan. karo@nupals.ac.jp.
authors.forename: Mineko
authors.initials: M
authors.lastname: Karo
authors.affiliation: Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan. mhayashi@nupals.ac.jp.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, 1-1Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan. atomic@bios.tohoku.ac.jp.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Fujii
keywords: beans; high hydrostatic pressure; water absorption, kinetic analysis