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High-quality fermented foods are the results of systematic decision-making and implementation based on traditional brewing techniques, regional geographical environment, consumption demand and regional customs. Specifically, traditional brewing is an industrial practice that integrates many natural and humanistic elements such as natural environment, Chinese history and culture, skill inheritance, scientific and technological innovation, scientific management, brand marketing, consumption habits, and social responsibility on the basis of inheriting the philosophy of "harmony between nature and man, Taoism and nature". Objectively, the above elements are ultimately reflected in the product quality by affecting the composition and function of brewing microorganisms. Based on the existing quality expressions of producing areas, estates, and standards, the theory of "brewing terroir" was put forward systematically, and a scientific expression system of traditional brewing techniques and product quality from the three dimensions of "natural terroir, humanistic terroir, and microbial terroir" was established taking Baijiu as an example, providing a theoretical and practical basis for the "quality visualization" of brewing products in the new consumption era.

The unreasonable planning of the access location and capacity of distributed generation (DG) affects the distribution network. The flexible power distribution unit has the advantages of flexible power flow distribution and voltage improvement. The steady-state calculation model and control strategy model of the flexible distribution unit are put forward. In order to locate and fix the capacity of DGs more reasonably, the comprehensive acceptance standard model of three indexes, namely life cycle cost (LCC), network loss and voltage deviation are established firstly. Then, the improved sparrow search algorithm (ISSA) is proposed to solve the model. Gaussian variation and Tent chaos are introduced to improve the global searching ability and convergence speed of the algorithm. Finally, the IEEE 33-node distribution system is taken as an example for simulation analysis. Considering the two cases of unconnected and connected flexible distribution unit respectively, particle swarm optimization (PSO) algorithm, sparrow search algorithm (SSA) and ISSA are used to solve the problem. The results show that the power flow of the system and the system operating status after the DGs are configured can be improved by taking into account the flexible distribution unit. And the optimization result of the ISSA is more efficient and accurate than the optimization results of other algorithms.

The organic acids and microbial community structure of fermented grains in the dominant stacking fermentation rounds for sauce-flavor Baijiu production (i.e., the 2nd and 3rd rounds corresponding to the 3rd and 4th rounds of base liquor) were analyzed using high-performance liquid chromatography (HPLC) and high-throughput sequencing, and the interaction between them was investigated. The results revealed that lactic acid, acetic acid, and succinic acid were the primary organic acids present in fermented grains at mean values of 32.70, 4.87 and 1.93 mg/g, respectively. In total, 8 dominant bacterial genera and 7 dominant fungal genera (average relative abundance > 1%) were identified across the two fermentation rounds. The dominant bacterial genera were Virgibacillus, Kroppenstedtia and Bacillus. The dominant fungal genera were Monascus, Thermomyces and Thermoascus. Principal coordinate analysis (PCoA) revealed that there was a significant difference in the structure of bacteria community between the second and third rounds of stacking fermentation, while the difference in the structure of fungal community was not significant. Co-occurrence network analysis showed that the bacterial-fungal (55.60%), bacterial-bacterial (50.57%), and fungal-fungal (91.67%) networks were mainly positively correlated, and there were more unknown interactions between bacterial communities. Mantel test analysis showed a significantly positive correlation between acidity and bacterial community structure (P < 0.01), and succinic acid was highly correlated with both bacterial and fungal community succession (P < 0.01). Spearman’s correlation analysis revealed that the bacterial community had a more significant correlation with organic acids than the fungal community, while the fungal community showed a negative correlation with most organic acids. Nine organic acids citric acid were positively correlated with Oceanobacillus, Bacillus, and Sphingobacterium but negatively correlated with Thermoactinomyces. The results of this study can provide a theoretical basis for the production of high-quality sauce-flavor Baijiu.

Gas chromatography-mass spectrometry (GC-MS) and electronic tongue were used to quantitatively determine the volatile compounds and taste indices of 21 Jiang-flavor baijiu samples of different grades. These samples were differentiated by chemometrics, and key differential compounds among grades were identified. Finally, a discriminant model was established by machine learning. The results showed that there were differences in the contents of volatile compounds in Jiang-flavor baijiu of three grades, indicating the feasibility of further discriminant analysis. The total content of flavor compounds in second-grade baijiu (4 908 mg/L) was significantly lower than that in premium-grade (6 583 mg/L) and first-grade baijiu (8 254 mg/L), while the proportion of several esters responsible for floral and fruity aromas in total esters showed a decreasing trend as the grade decreased. Partial least squares-discriminant analysis (PLS-DA) identified 16 key differential compounds represented by ethyl palmitate and acetic acid. The results of electronic tongue showed that the taste indexes of premium-grade baijiu were more consistent, with lower bitterness and astringency aftertaste. The taste indexes of second-grade baijiu showed significant intersample differences. Principal component analysis (PCA) showed clear discrimination of Jiang-flavor baijiu of different grades according to their taste indexes. The above results provide a basis for the establishment of Jiang-flavor baijiu quality system. Four discriminant models were established based on 25 differential compounds and taste indexes identified. The accuracy of all models was higher than 90%, and the support vector machine (SVM) model performed best, with an accuracy of 100%.

This study evaluated the β-glucosidase activities of 10 strains of Lactobacillus plantrum, L. helveticus, L. pentosus, and Streptococcus thermophilus) and compared the fermentation performance of the strains and the antioxidant properties and flavor quality of soymilk fermented by each of these strains. Moreover, the contents of isoflavones in fermented soymilk were analyzed. The results showed differences in the β-glucosidase activity of the different LABs, all of which showed good growth in soymilk, and L. plantarum was more suitable for growth in soymilk. LAB fermentation promoted the conversion of soybean isoflavones to active aglycones, and improved the nutritional characteristics of soymilk. Meanwhile, LAB changed the composition and content of volatile components, and effectively reduced the contents of hexanal, nonanal and 2-pentylfuran, which have been reported to be responsible for beany flavor, while retaining the characteristic aroma compounds of soymilk. Strains LPL044 and LPL051, with the highest β-glucosidase activity, showed the strongest ability to convert soymilk isoflavones, and the fermented soymilk had the highest contents of total phenols and total flavonoids, the strongest antioxidant activity and the best sensory quality, so they have greater research and development value compared with the other LABs.

Autonomous Rail Rapid Transit (ART), featuring multi-axles, high tire pressure, and complete channelization, leads to severe rutting on conventional asphalt pavements. Semi-flexible pavement materials (SFP) were applied to ART corridors to mitigate rutting. Mechanical response characteristics were obtained by embedding sensors to understand the interaction between ART and SFP. Results found that the damage of corridor pavement shifted from rutting to top-down transverse cracking after adopting SFP. Nonresidual longitudinal tensile strains primarily caused top-down transverse cracking. The compressive stress at the bottom of corridor pavement caused by ART is 41%, 36%, and 58% higher than that of the BUS, respectively, under the condition of constant speed, acceleration, and deceleration. The maximum strain response caused by ART under a high-temperature environment was ten times higher than that of buses. These findings can provide data support for numerical simulations, material failures, and structural damage of ART corridors. Highlights Mechanical responses of semi-flexible pavement materials influenced by Autonomous Rail Rapid Transit (ART) were first captured using sensors. ART with high tire pressure exhibits a multi-axial cumulative effect in high-temperature conditions, resulting in pavement strains that can be up to ten times those of buses. After adopting semi-flexible pavement, the damage in ART corridors shifted from rutting to top-down transverse cracking. Nonresidual longitudinal tensile strains are the underlying cause of top-down transverse cracking. [ABSTRACT FROM AUTHOR]

Graphene and its derivatives have garnered significant attention as novel nanomodifiers in the asphalt industry. Despite its vast potential, poor compatibility and dispersion between graphene and asphalt have been persistent challenges for researchers. To prepare well-dispersed graphene materials, polyvinylpyrrolidone (PVP) was grafted onto water-soluble graphene (WG), resulting in PVP-WG composites. This PVP-WG composite was introduced into matrix asphalt as a modifier to improve the compatibility and dispersion of graphene with asphalt. Various advanced techniques such as Fourier transform infrared spectroscopy, laser particle size analyzer, scanning electron microscopy, and X-ray diffraction confirmed the successful attachment of PVP to the surface of water-soluble graphene, thereby increasing the spacing between WG and promoting the intercalation of asphalt molecules. The loose structure of PVP facilitated the effective binding between WG and asphalt molecules. The multiple stress creep recovery and dynamic shear rheometer tests demonstrated that PVP-WG was effective in enhancing the elastic recovery performance, high temperature resistance to deformation, and viscoelastic properties of the asphalt binder. In addition, the results of the bending beam rheometer test showed that PVP-WG slightly reduces the low-temperature performance of asphalt, but PVP significantly improves the low-temperature cracking resistance of WG-modified asphalt. This study provides valuable insights into the potential application of graphene in asphalt pavement materials. [ABSTRACT FROM AUTHOR]