Frozen staple food, attributed to its favorable taste and convenience, has a promising development potential in the future. Frequent freezing and thawing, however, will affect its quality. This study simulated several freeze–thaw cycles (FTC) that may occur during the cold chain process of frozen oatmeal cooked noodles (FOCN) production to consumption. The quality changes and their mechanisms were elucidated using methods such as differential scanning calorimetry (DSC), low-field nuclear magnetic resonance (LF-NMR), Fourier-transform infrared spectroscopy (FTIR), confocal laser scanning microscopy (CLSM), texture analysis, and sensory evaluation. The freezable water content of the FOCN decreased because of the FTC treatment, and the relative content of total water in FOCN also decreased accordingly. The increase in β-Turn after FTC induced disorder in the secondary structure of proteins, causing the protein microstructure to become loose and discontinuous, which in turn reduced the water-holding capacity of FOCN. Additionally, FTC reduced the chewiness and sensory score of FOCN. This research will contribute a theoretical foundation for optimizing the cold chain process.
Utilizing natural hypoglycemic ingredients in staple foods is a safe and effective way to improve diabetes. High Tartary buckwheat noodles have garnered research interest due to their hypoglycemic properties. However, increasing the Tartary buckwheat content poses challenges in noodle processing and affects their edible quality. Effective resting is a critical link to improve the processing performance of noodle and edible quality of noodle. Therefore, research was conducted on ultrasound assisted resting of Tartary buckwheat dough (TBD) to explore its feasibility and mechanism in improving the quality of Tartary buckwheat noodle. The results indicated that ultrasound treatment effectively promoted the migration of weakly-bound water towards strongly-bound water, thereby enhancing the gluten protein network structure and increasing the α-helix and β-sheet contents significantly (p < 0.05). Furthermore, Texture analysis indicated decreased hardness and adhesion, and increased elasticity and stretching distance in the final noodles. Ultrasound-assisted maturation pre-treatment shortens TBD's dough's resting time and improves noodle quality, according to this study.
To investigate the optimal delivery system of quercetin, in this paper, cellulose nanocrystals (CNCs) extracted from rice bran were used to stabilize the Pickering emulsion and Pickering emulsion gels (PEGs) with quercetin. To compare the emulsion properties, stability, antioxidation activity, encapsulation rate, and bioaccessibility of the quercetin, four emulsions of CNC Pickering emulsion (C), CNC Pickering emulsion with quercetin (CQ), CNC Pickering gel emulsion (CG), and CNC Pickering gel emulsions with quercetin (CQG) were prepared. All four emulsions exhibited elastic gel network structure and good stability. The quercetin significantly reduced the particle size, increased the stability, and improved the antioxidant capacity of CQ and CQG. Compared to C and CG, the ABTS+ radical scavenging capacities of CQ and CQG were respectively enhanced by 46.92% and 3.59%. In addition, CQG had a higher encapsulation rate at 94.57% and higher bioaccessibility (16.17) compared to CQ. This study not only indicated that CNC from rice bran could be exploited as an excellent stabilization particle for Pickering emulsions, but also provided a highly stable and bioaccessible delivery system for water-insoluble functional active factors.