テーマ

冷却・凍結

研究機関名

University of Hawaii

代表者名

Dr. Soojin Jun

発表概要文

Supercooling technology keeps foods fresh below freezing points without ice formation, offering promising preservation solutions. However, its thermodynamic instability poses practical challenges. This study investigates the stability of supercooled agar gel samples under mechanical and thermal stress conditions exposed to oscillating magnetic fields (OMFs). Samples were treated with an OMF of 15 mT at 5 Hz, full cycle, to monitor the stability of supercooling over 24 hours at -5.5°C. The OMF-treated samples exhibited a 95% probability of maintaining supercooling, compared to only 10% in untreated controls, based on a sample size of 50 trials. Under mechanical stress, the OMF effectively stabilized samples during moderate orbital vibrations. However, when vertical vibrations exceeded a peak force of 0.6 g, the supercooled state was broken, indicating that specific force thresholds are critical in triggering ice nucleation. In simulated in-vehicle transportation tests, samples were supercooled at -4°C under various road conditions and speeds. The results indicate that OMF-assisted supercooling enhances stability in cold chain logistics.