Comparison of rheological behavior, microstructure of wheat flour doughs, and cooking performance of noodles prepared by different mixers

Study on the Quality Variation and Internal Mechanisms of Frozen Oatmeal Cooked Noodles during Freeze-Thaw Cycles

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.

Effect of superfine grinding chestnut powder on the structural and physicochemical properties of wheat dough

This study evaluated the influence of chestnut powder, produced using ball mill superfine grinding (BMSG), jet superfine grinding (JSG), and ordinary grinding (OG), on wheat flour properties. Blending wheat flour with chestnut powder resulted in a darker flour blend (3 % decline of L*), with decreased the tap density and increased water holding capacity. Adding appropriate proportion of superfine chestnut powder can bolster the mixed flour's thermal stability (15 % BMSG/JSG) and freeze-thaw stability (10 % BMSG/JSG), while significantly enhancing the anti-aging properties of flour products. The proposition of 5 % superfine BMSG/JSG did not significantly affect the tensile resistance of the dough, and even improve the dough's tensile strength. In addition, the hardness, adhesiveness, springiness and pH of fermentation increased due to the addition of chestnut powder, as supported by the dough texture analyses and fermentation characteristics findings. However, the excessive addition of chestnut powder affected the dough network's structural integrity to some extent. Further study can focus on the influencing mechanism of chestnut powder on gluten formation and related nutritional properties. Overall, this research underscores the potential of utilizing chestnut powder to enhance the nutritional and functional qualities of wheat-based products.

Effects of vacuum degree, mixing speed, and water amount on the moisture distribution and rheological properties of wheat flour dough

Effects of vacuum degrees (0.00, 0.02, 0.04, 0.06, 0.08 MPa) on water distribution state, tensile properties, stress relaxation properties, and viscoelasticity of dough, as well as the effects of mixing speed (50, 70, 90 rpm/min) and water content (40%, 45%, 50%) under optimum vacuum degree were studied. The results showed that the proper vacuum degree (0.06 MPa) could promote the full contact between flour and water and improved the water-holding capacity of the dough. Meanwhile, the dough had stronger tensile strength, the best viscoelasticity and the ability to recover from external deformation more quickly. Under the vacuum of 0.06 MPa, with the increasing of mixing speed, the response to the external force of dough increased first and then decreased. Adding more water reduced the strength of dough, weakened the response to external forces, and led to a significant decrease in tensile resistance and tensile area of the dough, as well as a decrease in viscoelasticity (p < 0.05). The proper vacuum mixing allowed the preparation of dough to require more water and less energy. PRACTICAL APPLICATION: In the processing of wheat flour products, vacuum mixing is considered to be beneficial to the quality of noodles and breads. As the intermediate of these products, the dough is of great significance for the monitoring of its rheological characteristics. In this study, a moderate vacuum degree led to a significant improvement in the rheological properties of the dough, and the processing performance was the best. Under the optimal vacuum degree, the influence of mixing speed and water amount cannot be ignored. Vacuum mixing is an efficient dough preparation method, which can produce certain economic benefits.