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ARS Home » Pacific West Area » Hilo, Hawaii » Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center » Tropical Crop and Commodity Protection Research » Research » Publications at this Location » Publication #418562

Research Project: Postharvest Protection of Tropical Commodities for Improved Market Access and Quarantine Security

Location: Tropical Crop and Commodity Protection Research

Title: Effect of oscillating magnetic field (OMF) on the supercooling behavior of iron-oxide nanoparticle (IONP) agar model system

Author
item JOYA, AMANDA - University Of Hawaii
item LEE, DONGYOUNG - University Of Hawaii
item KANG, TAIYOUNG - University Of Hawaii
item Wall, Marisa
item JUN, SOOJIN - University Of Hawaii

Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/21/2024
Publication Date: 1/20/2025
Citation: Joya, A., Lee, D., Kang, T., Wall, M.M., Jun, S. 2025. Effect of oscillating magnetic field (OMF) on the supercooling behavior of iron-oxide nanoparticle (IONP) agar model system. Journal of Food Science. 9(1) Article e70035. https://doi.org/10.1111/1750-3841.17653.
DOI: https://doi.org/10.1111/1750-3841.17653

Interpretive Summary: Freezing is a process of preserving food due to its low storage temperatures and reduced water activity that can extend the shelf-life of foods. However, freeze-induced ice crystal formation causes structural damage to foods, which substantially leads to negative impacts on food quality attributes. Oscillating magnetic field (OMF)-assisted freezing is posed as an effort to overcome the limitations caused by freezing. In this study, an agar food model combined with iron-oxide nanoparticles (IONPs) was made to determine ice nucleation parameters and supercooling behavior with and without exposure to an external OMF. The agar with IONPs had different ice nucleation and supercooling behaviors compared to non-magnetic nanoparticles. High supercooling probabilities (75-90%) were achieved for magnetized samples, supporting the concept of that OMF-assisted freezing can improve the current magnetic freezing technology to improve food quality.

Technical Abstract: Freezing is a process of preserving food due to its low storage temperatures and reduced water activity that can extend the shelf-life of foods. However, freeze-induced ice crystal formation causes structural damage to foods, which substantially leads to negative impacts on food quality attributes. OMF-assisted freezing is posed as an effort to overcome the limitations caused by freezing. However, magnetic field (MF) freezing remains a controversial topic, and many mechanisms have been proposed to understand the supercooling phenomena under external MFs. It has been proposed that natural materials containing ferric/ferrous materials have ferromagnetism that can contribute to the magneto-mechanical motion when exposed to OMFs during freezing, inhibiting the formation of ice nucleation and promoting supercooling. MF food freezing remains a topic of debate due to the complex matrices of food. In this study, an agar food model combined with ferric nanoparticles (IONPs) was made. The ice nucleation time and temperature were determined with and without exposure to an external OMF (10 mT, 10 Hz) for 24 h, and the supercooling behavior was examined. High supercooling probabilities were achieved in 3, 6, and 12 mg IONP agar samples of 75, 75, and 90%, respectively. Contrarily, the control and ZNP samples had 60 and 55% supercooling probabilities, respectively, which can be due to the stochastic nature of ice nucleation during the metastable supercooling state. Studies using magnetic field-based freezing technology with magnetic nanoparticles under OMF-assisted freezing can offer possible methods to improve the current magnetic freezing technology to improve food quality.