Effect of oscillating magnetic field on freezing process of model foods = ผลของสนามแม่เหล็กแบบสลับต่อกระบวนการแช่แข็งโมเดลอาหาร


ภัคจิรา จารุเลิศวัฒนา


วิทยานิพนธ์. (2016) 130 หน้า



Magnetic field-assisted freezing has recently received much attention both from food industry and scientific community. Many patents have claimed that magnetic field can enhance vibration of water molecules, resulting in breakage of hydrogen bonds, which leads to prevention of ice crystal nucleation and promotion of supercooling. However, only a few researchers have reported the effect of magnetic field on food freezing and most of the results are inconclusive. The purpose of this research was to investigate the effet of oscillating magnetic field in the range of 0-12 mT (50 Hz) on the temperature profile (i.e., freezing rate and phase transition time) and quality (i.e., drip loss, hardness,number of peaks and gradient) of model foods during freezing in an air blast freezer at -10±3 °C. deionized water and potato were used as model foods in this study. The samples were placed in the middle of 2 magnetic cores where an oscillating magnetic field was applied. Temperature profiles wre recorded in all experiments and texture profile was analyzed for thawed potato samples. No significant differences in the freezing rate, phase transition time, drip loss and texture profile of potatoes were observed when applying or not applying magnetic field (p>0.05). In conclusion, oscillating magnetic field under 12 mT had no effect on the freezing process of model foods and, thus, was unable to improve the frozen food quality