Supercooling preservation technology in food and biological samples: a review focused on electric and magnetic field applications

Abstract

Freezing has been widely recognized as the most common process for long-term preservation of perishable foods; however, unavoidable damages associated with ice crystal formation lead to unacceptable quality losses during storage. As an alternative, supercooling preservation has a great potential to extend the shelf-life and maintain quality attributes of fresh foods without freezing damage. Investigations for the application of external electric field (EF) and magnetic field (MF) have theorized that EF and MF appear to be able to control ice nucleation by interacting with water molecules in foods and biomaterials; however, many questions remain open in terms of their roles and influences on ice nucleation with little consensus in the literature and a lack of clear understanding of the underlying mechanisms. This review is focused on understanding of ice nucleation processes and introducing the applications of EF and MF for preservation of food and biological materials.

Keywords: Electric and magnetic field; Food preservation; Freezing; Supercooling.

Fig. 1

(A) Homogeneous nucleation. (B) Changes in the free energy of a spherical nucleus of radius r during homogeneous nucleation based on the CNT (Karthika et al., 2016). (C) Heterogeneous nucleation on a surface. (D) Comparative representation of the Gibbs free energy for homogeneous ($\mathrm{\Delta }{\text{G}}_{hom}^{\ast }$) and heterogeneous ($\mathrm{\Delta }{\text{G}}_{\text{het}}^{\ast }$) (Çelikbilek et al., 2012)

Fig. 2

Typical time–temperature profiles of water during freezing and supercooling processes

Fig. 3

Color differences (A–D) and microstructure images (E–G) of fresh-cut pineapples preserved at different storage conditions (refrigeration: 4 °C, freezing: − 18 °C, and supercooling: − 7 °C) for 14 days: fresh (A, E), refrigeration (B), freezing (C, F), and supercooling (D, G) (Kang et al., 2019)

Fig. 4

Schematic diagram of experimental set-up for the combination treatment of pulsed electric field (PEF) and oscillating magnetic field (OMF) (You et al., 2020)

Fig. 5

Schematic diagram of changes in Gibbs free energy and the critical nucleus radius by an electrostatic field during freezing process of water. Modified from Dalvi-Isfahan et al. (2017b)

Fig. 6

Summary of the effects, mechanisms, and key published studies on electric and magnetic fields-assisted controlled ice nucleation during freezing