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The maturation of wheat flour is a transformative process that elevates its processing and culinary attributes to their peak performance levels. Despite extensive research on starch and gluten protein modifications, the impact of lipid changes has been largely unexplored. This study addresses this gap by examining the maturation of freshly milled wheat flour at 15 °C, 25 °C, and 40 °C over 60 days, focusing on enzymatic activities—lipase, lipoxidase, and catalase—and lipid metabolites, including free fatty acids, conjugated trienes, p-anisidine value, and total oxidation value. The results of this study showed that free fatty acids continued to increase at all temperatures, with the most significant increase of 50% at 15 °C. The p-anisidine value followed a pattern of initial increase followed by a decline, while conjugated trienes were markedly higher at 40 °C, suggesting temperature's significant influence on lipid peroxidation. Notably, total oxidation values became erratic post 30 days, indicating a shift in oxidative dynamics. This study underscores the correlation between lipid metabolites and enzymatic activities, revealing the enzymes' pivotal role in lipid oxidation. The interplay of temperature and time offers valuable insights for optimizing wheat flour maturation, ensuring superior quality for various applications. [ABSTRACT FROM AUTHOR]

Lateral erosion is a critical factor that influences the formation and amplification of debris flows. However, our understanding of the bank retreat process in debris flow channels is limited, which limits the evaluation of debris flow magnitudes and the prediction of their activity trends. Herein, we conduct physical experiments to investigate bank retreat mechanisms using five types of bank soil and multiple debris flow surges. The bank retreat process is categorized into two stages: toe cutting and bank collapse. Toe cutting is mainly caused by hydraulic erosion, bank collapse includes gravity erosion in the form of toppling failure. Notably, the bank retreat process exhibits a significant negative feedback loop. Bank erosion widens the channel bed, subsequently decreasing the flow depth. In turn, this reduction in flow depth mitigates bank erosion. Moreover, we discover a concise pattern in the complex coupling of hydraulic erosion and toppling failure: erosion efficiency is linearly and negatively correlated with the bed widening width. We develop a new parameterized model for describing the bank retreat process and provided empirical values for the model parameters. Furthermore, we observe that the initial erosion efficiency first increases and then decreases with an increase in the fine particle content of the bank soil. Additionally, we report a negative correlation between the maximum bed widening width and the fine particle content in the bank soil that follows a power function relationship. Key Points: We revealed the feedback mechanism between bank retreat and debris flow erosion efficiencyWe established a parameterized model describing the bank retreat processWe discussed the relationships between the model parameters and the particle size distribution of the bank soil [ABSTRACT FROM AUTHOR]

The effect of adding sourdough with lactic acid bacteria (Lactobacillus plantarum M616) on dough quality and the sensory scores, specific volume, crumb firmness, and spread ratio of resultant Chinese steamed bread were studied. The moisture content of crumb and texture characteristics of the Chinese steamed bread with sourdough during storage were analyzed. In this study, 10%, 20%, 30%, and 40% of sourdough addition was investigated. The sourdough starter resulted in significant decrease in the water absorption, development time, stability, and farinograph quality number of the dough. The addition of sourdough improved the quality of Chinese steamed bread such as improving the sensory scores and specific volume, decreasing the crumb firmness, and a lower spread ratio was observed with an increase in the sourdough concentration up to 30%. Sourdough addition delayed a fast decrease in the moisture content of the Chinese steamed bread crumb during storage. The texture profile analysis of the bread crumb indicated that the addition of sourdough improved the quality and delayed the staling speed of Chinese steamed bread during storage. Moreover, inclusion of 30% sourdough produced the best protective effect on product staling.Supported by National Natural Science Foundation of China (31571780), Key Research Project in Higher Education of Henan (18A550002), Zhengzhou Science and Technology Innovation Team Program (121PCXTD518), School Funds of Henan University of Technology (2017QNJH11), and High-level Talent Foundation of Henan University of Technology (2017BS005) Keywords:: Sourdough, Chinese steamed bread, Dough quality, Shelf life, Texture profile analysis

To clarify the effect of NaCl concentration (0–2.0%) on the formation of amyloid fibrils (AFs) in cooked wheat noodles, the morphology, surface hydrophobicity, secondary structure, molecular weight distribution, microstructure, and crystal structure of AFs were investigated in this paper. Fluorescence data and Congo red stain images confirmed the presence of AFs and revealed that the 0.4% NaCl concentration promoted the production of AFs. The surface hydrophobicity results showed that the hydrophobicity of AFs increased significantly from 3942.05 to 6117.57 when the salt concentration increased from 0 to 0.4%, indicating that hydrophobic interactions were critical for the formation of AFs. Size exclusion chromatography combined with gel electrophoresis plots showed that the effect of NaCl on the molecular weight of AFs was small and mainly distributed in the range of 5–7.1 KDa (equivalent to 40–56 amino acid residues). X-ray diffraction and AFM images showed that the 0.4% NaCl concentration promoted the formation and longitudinal growth of AFs, while higher NaCl concentrations inhibited the formation and expansion of AFs. This study contributes to the understanding of the mechanism of AF formation in wheat flour processing and provides new insight into wheat gluten aggregation behavior. [ABSTRACT FROM AUTHOR]

Solvent retention capacity (SRC) is a test for the solvation of wheat flour. Its functional contribution was predicted according to the swelling behavior of different diagnostic solvents to different polymeric components of wheat. Ten commercial wheat flour varieties were used as raw materials in this study. The flour quality, gluten aggregation and solvent retention capacity, and their correlations were analyzed. The results showed that protein content, wet gluten content, dry gluten content and the swelling index of glutenin were positively correlated with torque maximum (BEM), torque 15 s before maximum torque (AM), torque 15 s after maximum torque (PM) and gluten aggregation energy (AGGEN). Moreover, they were significantly correlated with the solvent retention capacity. BEM, AM, PM and AGGEN were positively correlated with standard solvent water-SRC (WSRC) and lactic acid-SRC (LASRC). For supplemental solvents, ethanol-SRC (EthSRC) was positively correlated with AGGEN. Sodium dodecyl sulphate-SRC (SDSSRC) was highly correlated with peak maximum time (PMT). Metabisulfite-SRC (MBSSRC) and MBS + SDSSRC were also significantly correlated with BEM, AM, PM and AGGEN sodium metabisulfite. There were significant correlations between gluten aggregation characteristic, standard SRC solvent and supplemental solvent. This study provides a theoretical basis for the evaluation of wheat flour quality. [ABSTRACT FROM AUTHOR]

The effect and mechanism of sanxan on the quality of salt‐free noodles (SFNs) were investigated from different cooking stages (initial stage, 1 min; optimum cooking time, OCT; overcooked time, OT). The results showed significant changes in the cooking process with the addition of 1.2% sanxan. The OCT for noodles with 1.2% sanxan (experimental group, EG) was extended from 5 to 7 min compared to the non‐added noodles (blank group, BG) and 1.5% salt‐containing noodles (control group, CG). The hardness and adhesiveness of BG, EG, and CG all decreased significantly during cooking. In contrast, the springiness, maximum tensile strength, and tensile fracture distance trended first to increase and then to decrease. At OCT, EG had the highest hardness (3971.69 ± 94.49 g), adhesiveness (372.26 ± 33.56 g s), and maximum tensile strength (41.51 ± 2.76 g), which remained large even after overcooking. However, those in BG and CG showed a significant reduction (p < 0.05). The proportion of free water increased progressively as cooking progressed, with CG showing the largest increase, from 82.29% to 91.19%, whereas EG showed the smallest increase, from 78.34% to 86.02%. During the cooking process, the addition of sanxan delayed the water migration, whereas salt promoted it. Sensory evaluation showed that EG was smoother in appearance than BG and tasted malty with a slight stickiness. Moreover, EG had the smallest k1 and C∞ values. Thus, sanxan is an effective additive to enhance the quality of SFNs and can replace the role of salt in noodles in some properties, which is beneficial for the development of SFNs. [ABSTRACT FROM AUTHOR]