Effects of magnetic field on freezing characters of carrot, potato and broccoli

Abstract

In order to study the effects of magnetic field on the freezing characteristics of fruits and vegetables, carrot, potato and broccoli were frozen without and with a magnetic field of intensities 4.6 Gs, 9.2 Gs, 18 Gs and 36 Gs, while recording the temperature changes. The microstructure and temperature change of carrot during freezing were analyzed in detail. The results show that the magnetic field has effects on the freezing process of carrot strips, characterized by a reduction of the phase transition time and a characteristic diversity of the ice crystal formation zone. Crystallization characteristics are similar in the samples without and with a magnetic field of low intensities (4.6 Gs and 9.2 Gs), which show as a non-homogeneous phase transition process in the carrot sample, and the tissue changed showing a sunken, cell morphology variation and increased intercellular space. The freezing is almost homogeneous under a magnetic field of intensities 18 Gs and 36 Gs, then results in a slightly change of cell morphology. In addition, the effects of magnetic field on fruits and vegetables are varying with their species.