Ma Youchuan, Bi Jinfeng, Wu Zhonghua, Yi Jianyong
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China.
College of Mechanical Engineering, Tianjin University of Science and Technology, Tianjin, China.
J Sci Food Agric. 2025 Sep;105(12):6729-6736. doi: 10.1002/jsfa.14381. Epub 2025 May 23.
The physical quality of freeze-dried food products is defined by their porous morphology. To enable efficient regulation of the physical quality of fruits and vegetables, pectin-sucrose cryogels were selected as a model system. Cryogels frozen under varying magnetic field conditions were subsequently freeze-dried, and their drying characteristics, microstructure, texture, and rehydration properties were analyzed.
A vacuum freeze-dried pectin cryogel system was developed to simulate the natural network structure of fruits and vegetables. The results showed that magnetic field-assisted freezing led to the formation of a small and lamellar pore structure in cryogels. Additionally, the drying time for samples frozen at -20 °C and subjected to a 10 mT magnetic field was comparable to the control group with no magnetic field, but the rehydration rate was higher (10.37 g g). Correlation analysis showed that magnetic field strength had a significantly negative correlation with drying rate, number of peaks, maximal force, and positive area (P < 0.05), and a significantly positive correlation with rehydration rate (P < 0.05).
Magnetic field-assisted freezing produced small lamellar porous structures, which enhanced the product's rehydration and texture quality. © 2025 Society of Chemical Industry.
冻干食品的物理品质由其多孔形态决定。为了有效调控水果和蔬菜的物理品质，选择果胶 - 蔗糖冷冻凝胶作为模型体系。随后对在不同磁场条件下冷冻的冷冻凝胶进行冻干，并分析其干燥特性、微观结构、质地和复水特性。
开发了一种真空冻干果胶冷冻凝胶体系以模拟水果和蔬菜的天然网络结构。结果表明，磁场辅助冷冻导致冷冻凝胶中形成小而层状的孔结构。此外，在 -20°C 下冷冻并施加 10 mT 磁场的样品的干燥时间与无磁场的对照组相当，但复水率更高（10.37 g/g）。相关性分析表明，磁场强度与干燥速率、峰数、最大力和正面积呈显著负相关（P < 0.05），与复水率呈显著正相关（P < 0.05）。
磁场辅助冷冻产生了小的层状多孔结构，提高了产品的复水性和质地品质。© 2025 化学工业协会。
