AIST Stories No2

Impact in the following fields! Community lifeIndustry◦Food◦‌‌Medical treatment, welfare, care giving◦Food products◦Distribution and retailing◦Agriculture and fisheries◦‌‌Medical treatment, biotechnology25AIST supporting livelihoods! at a glanceTerminologySherbet-like ice discharged from ice-making machine*1 Ikejime: The process of quickly destroying the motor center of a just-landed fish to prevent it from flopping around. *2 Ice thermal storage system: Exploiting the fact that electricity tariffs are cheaper at night compared with daylight hours, ice is prepared at night and utilized in the daytime for air-conditioning.*3 Supercooled water: A state whereby water is cooled to a temperature lower than 0°C while remaining a liquid and not solidifying.Photograph:‌Nikko‌Photograph:‌NikkoPhotograph:‌NikkoHokkaido‌Industrial‌Technology‌Center“Kaihyo (Silk Ice)” sherbet-like brackish ice ice-making machine◀‌‌Pacific saury stored with sherbet-like brackish ice (bottom) is fresher than the same fish stored using conventional means (top). For this reason, its market price is higher and it can also be beneficial in fish branding and differentiation.accumulation of such fundamental research, a prototype of an ice-making machine that could form sherbet-like ice with diameters of just 8 μm (μ: 10–6) was completed in 2011.Expectations for QOL enhancement and promotion of local industryThe cooperation of people in the fisheries field was obtained in commercialization of the ice-making machine, which was actually installed in a fishing boat. Numerous field tests were conducted, onsite issues such as the effects of pitching and rolling of the boat on safety and machine reliability were noted, and improvements were made. In addition, whether sherbet-like brackish ice actually improved freshness retention was verified with cooperation from experts from the Hokkaido Industrial Technology Center. The findings proved that there was a substantial freshness retention effect. Then, in 2013, Nikko commercialized its Kaihyo (Sea Ice) Continuous Silk Ice System.The sherbet-like ice made with this ice-making machine is revolutionary in that it has a soft texture that does not damage the fish, it can cool fish to below the freezing point in one-fifth of the time required by traditional crushed ice and moreover, it can retain this temperature. The ice is made from seawater so there is no need to carry water on board the ship, and the ice-making cost can be lowered significantly.“This technology can also be applied in the medical field in low-temperature surgery and in the food industry in the freezing of food. I think it can contribute to improving QOL (quality of life) in various fields.” In addition, Nikko anticipates that the technology will lead to the promotion of local industry in Hokkaido, where it is based.Ice-making machine for sherbet-like brackish iceFirst, a refrigerant is fed into the upper left of the ice-making machine to cool its inner wall. Next, seawater flows in (lower left) and the inner wall cool the seawater to form small ice particles. When the scraper is then rotated, sherbet-like brackish ice is continuously formed and by scraping this off, sherbet-like brackish ice is discharged (upper right).RotationScraperRefrigerant inputDischarge brackish iceSeawater inputDischarge refrigerant