Araki, T., Du, K., Ueno, S., Kono, S., Do, G., Maeda, T. 2018 Effects of frozen storage and thawing conditions on physical properties of glutinous rice: (part 2) rheological measurement. ⇒ J-Stage Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers, 35(3), 237-244. Abstract The effects of the freezing process and frozen storage periods on rheological parameters of freshly cooked and freeze-thawed glutinous rice have been investigated. Cooked glutinous rice (cv. Koganemochi) was frozen and stored in a household freezer at -20°C for 1, 5, 10, 30 and 60 days. After steaming and natural thawing processes, creep-recovery test (0.1N, small deformation), texture profile analysis (TPA) test (50% deformation) and the tensile testing (20N, 100% deformation) were performed on one-grain and block-shaped glutinous rice respectively by a rheometer, to measure the rheological parameters of the samples. One-grain samples showed more significant differences with freshly cooked rice in tensile testing, while blockshaped ones showed more in creep recovery tests. There were few significant differences in any fracture characteristics and viscoelastic properties between steaming and natural thawing methods for both block-shaped and one-grain samples in each storage period. The TPA results demonstrated …
Effects of frozen storage and thawing conditions on physical properties of glutinous rice: (part 2) rheological measurement
Effects of frozen storage and thawing conditions on physical properties of glutinous rice: (part 1) ice crystal and color measurement
Araki, T., Du, K., Ueno, S., Kono, S., Do, G., Maeda, T. 2018 Effects of frozen storage and thawing conditions on physical properties of glutinous rice: (part 1) ice crystal and color measurement. ⇒ J-stage Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers, 35(3), 231-236. Abstract The effect of the freezing process and frozen storage periods on the microstructure of cooked glutinous rice has been investigated. Cooked glutinous rice (cv. Koganemochi) was frozen and stored in a household freezer (about -22 °C) during 1, 5, 10, 30 and 60-day storage periods. Its microstructure was observed by using fluorescence staining method and the morphology of ice crystals including equivalent diameter and number was analyzed. Colorimetric measurements were conducted after natural and steaming thawing on samples of each storage period. It was found that average equivalent diameter and number of ice crystals increased with storage period from 5 days, and recrystallization occurred in temperature fluctuation during freezing process and storage affected microstructure of glutinous rice. Moreover, by analyzing the distribution of ice crystals, it was found that most of them are under 10µm in each storage period. Frozen stored glutinous …
Effect of freezing and thawing on the quality of durian (Durio zibethinus Murray) pulp
Tagubase, J. L., Ueno, S., Yoshie, Y., and Araki, T. 2016. Effect of freezing and thawing on the quality of durian (Durio zibethinus Murray) pulp ⇒_pdf ⇒J-STAGE Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers 33: 267-272. (査読有) Summary The effect of freezing, and iced and hot water thawing on the quality of durian pulp was investigated. Mature durian pulp was removed with seeds, vacuum-packed, and frozen at -20°C. Thawing in iced water (~0°C) and hot water (~90°C) was then applied and the quality of the pulp was assessed based on physicochemical properties (pH, moisture content, soluble solids concentration (SSC), color, sugar content (sucrose, glucose, and fructose), and organic acid content (succinic acid and citric acid ), texture and smell profile. Overall, the freezing and thawing conditions, particularly the hot water thawing, posed an effect to the moisture content, color, and smell profile of the durian pulp. A significant increase in the moisture content, as well as a decrease in the color brightness was observed. Furthermore, the hot water-thawing process also induced slight variation to the smell attribute and strength of the entirety of smell. Although the …