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As an emerging physical technology, magnetic fields have been used to improve the quality of frozen and refrigerated foods. This study compared the effect of applying a static magnetic field (2 mT) at different stages of freezing and storage on the quality of frozen dough. Results suggested that the magnetic field significantly impacted frozen dough quality. It not only prevented the formation of ice crystals during the pre-freezing stage but also inhibited ice crystal growth during the following frozen storage. This effect helped to maintain the integrity of gluten proteins and their adhesion to starch granules by preventing the breakage of disulfide bonds and the depolymerization of gluten macromolecules. It was also observed that yeast inactivation and glutathione release were reduced, resulting in improved air retention and air production capacity of the dough. This, in turn, led to a more appealing volume and texture quality of the finished bread. • Magnetic field (MF) improved volume and texture quality of frozen wheat dough. • MF inhibited ice crystal formation and growth during pre-freezing and frozen storage. • MF prevented disulfide bond breakage and gluten macromolecule depolymerization. • Yeast inactivation and glutathione release were reduced under MF. [ABSTRACT FROM AUTHOR]

This study was to investigate the protective effect of magnetic field (MF) on frozen dough processing quality. The texture, microstructure, rheological and physicochemical properties of wheat dough treated by freezing-thawing cycles under different magnetic flux densities (0, 2, 4, 6, 8, and 10 mT) were analyzed. Compared with conventional frozen dough, MF-treated frozen dough had lower hardness and higher elasticity. Scanning electron microscope exhibited that MF treatment minimized the freezing-induced damages on morphology of starch and gluten, which was consistent with the decreased tan δ in rheological analysis. Application of MF facilitated high relative crystallinity and gelatinization enthalpy in starch granules while the depolymerization of gluten macropolymer was inhibited as manifest with more ordered secondary structure and decreased free sulfhydryl groups. The integrated structure in MF-treated frozen dough resulted in lower free water content as shown by low field nuclear magnetic resonance. The results provided valuable knowledge for the MF-assisted freezing technology and made it possible to improve the freezing-induced deteriorations on wheat-based food. • Wheat dough was frozen/thawed with different magnetic field(MF) intensities. • Freezing-induced damages on starch granule and gluten were repaired by MF. • MF resulted in high starch crystallinity and lower gluten depolymerization. • MF caused a softer hardness and higher elasticity compared with frozen dough. [ABSTRACT FROM AUTHOR]