Birth cohort changes in anxiety levels among primary school students in China during 1995-2019: A cross-temporal meta-analysis.

To investigate birth cohort changes in anxiety levels among primary school students in China, we conducted a cross-temporal meta-analysis of 126 studies (N = 109,957) reporting the anxiety levels among primary school students in China during 1995-2019 using the Mental Health Diagnostic Test (MHT); higher MHT scores indicated higher anxiety. The results showed that: (1) The MHT scores for five types of mental health problems (social anxiety, lonely tendency, physical symptoms, terror tendency, and impulsive tendency) and the total MHT score were significantly negatively correlated with the data-collection year, indicating that the anxiety levels among primary school students in China decreased over time. (2) The MHT score for learning anxiety was significantly positively correlated with the data-collection year, indicating that the learning anxiety levels of primary school students in China increased over time. (3) The overall MHT score did not show significant gender differences, but gender-wise varying trends were observed in the types considered.

Interactions between kafirin and pickle-like odorants in soy sauce flavor Baijiu: Aroma profile change and binding mechanism.

The pickle-like odor, which was caused by the excess volatile sulfur compounds (VSCs), is an undesirable odor in soy sauce flavor Baijiu (SSB). The aim of this study was to explore the suppressing effect of kafirin, the internal prolamin of the raw material of Baijiu, on the pickle-like odor of SSB. The instrumental analysis (comprehensive two-dimensional gas chromatography, ultraviolet and visible spectrophotometry), human perceptions (aroma profile, odor thresholds) and in silico analysis methods (molecular docking) were combined to detect the changes of the pickle-like odor. After the addition of kafirin, the aroma profile of the pickle-like SSB changed and approached to that of the normal SSB. The volatility and the odor thresholds of VSCs decreased 22.05%-64.28% and increased 87.29%-232.57%, respectively. In conclusion, kafirin exhibited a significant suppressing effect on the pickle-like off-odor of SSB, and this effect could be used to reduce the off-odor of SSB and SSB-derived alcoholic beverages.

Structural characterization and antioxidant properties of a novel polysaccharide isolated from Jiuzao in vitro and in vivo.

Recovery of valuable compounds from Baijiu by-products is one of the important challenges currently faced by the brewing industry. In recent years, the research on Baijiu has shifted from Baijiu flavour to functional compounds, especially the extraction and activity of Jiuzao polysaccharides. The polysaccharide from Laowuzeng Jiuzao (LWZ-P') was extracted by water extraction and alcohol precipitation, and then purified by column chromatography to obtain pure polysaccharide. The physical and chemical properties of LWZ-P' were analyzed by UV, FT-IR, GPC, NMR, and HPAEC. As a result, LWZ-P' was mainly composed of mannose (37.26 %), with a relative molecular weight of 32 402 g/mol, possessing the primary backbone of â†’ 3)-α-d-Manp-(1 â†’ and â†’ 2)-α-d-Manp-(1 â†’ with branches consisting of α-d-Manp-(1 â†’ residue. In addition, LWZ-P' had significant activities of DPPH radical, ABTS free radical, superoxide anion free radical and hydroxyl free radical in a dose-dependent manner. Meanwhile, LWZ-P' presented a protective effect against the generation of H2O2-induced reactive oxygen species, effectively inhibiting cell death in zebrafish. The current study aims to recover polysaccharides from brewed products, better understand the functional value of Jiuzao, and lay a theoretical foundation for the development of Jiuzao polysaccharide-related foods.

A flavoromics strategy for the differentiation of different types of Baijiu according to the non-volatile organic acids.

Non-volatile organic acids (NVOAs) in 12 main flavor types of Baijiu were analyzed by a derivatization method combined with GC-MS and 38 NVOAs were quantified. Meanwhile, a flavoromics strategy based on the contents of NVOAs in the 12 flavor types of Baijiu was successfully used to the differentiation of Baijiu. PLS-DA models (explained variation, predictive capability) were used to consider different categories: fermentation process (0.931, 0.870), starter (0.921, 0.834), fermentation container (0.899, 0.810) and raw material (0.951, 0.909). Based on the selected categories, suitable separations were achieved, and the classification ability of these models were nearly 100%. As a result, the model demonstrated its ability to perfectly distinguish different types of Baijiu. Seventeen potential markers were identified by variable importance in projection method and were further processed using heatmap and hierarchical cluster analysis, indicating that the NVOAs had great discrimination power to differentiate Baijiu.

Analysis, occurrence, and potential sensory significance of tropical fruit aroma thiols, 3-mercaptohexanol and 4-methyl-4-mercapto-2-pentanone, in Chinese Baijiu.

Fruity notes are important to the flavor of Baijiu (Chinese Liquor) and are considered to originate from ester compounds; however, little is known about the other chemicals that contribute to the fruity aroma. In this study, the sensory impacts of two tropical fruit aroma thiols, 3-mercaptohexanol (3MH) and 4-methyl-4-mercapto-2-pentanone (4MP), in Chinese Light-, Strong- and Soy sauce flavor type Baijiu were systemically subjected to a sensory evaluation, qualitative and quantitative analysis, and multivariate statistical analyses. The flavor dilution factors of 3MH and 4MP were 9-729. The contents of 3MH and 4MP were the highest (p < 0.001) in Strong- and Soy sauce aroma-type Baijiu, respectively. According to their odor activity values (OAVs), 3MH (OAV: 1-22) and 4MP (OAV: 1-9) are important to the aroma of Baijiu. Notably, 4MP was identified for the first time in Baijiu, and the multivariate statistical analysis demonstrated that 3MH and 4MP could be used to differentiate Baijiu.

High-throughput sequencing of the microbial diversity of roasted-sesame-like flavored Daqu with different characteristics.

The purpose of this experiment was to analyze the microbial community diversity in three Daqu samples displaying different characteristics in the same Daqu fermentation chamber. A high throughput sequencing technique was used to detect the microbial abundance and diversity in these Daqu samples. Of the three samples, the microbial diversity in the Black sample (sample B) was significantly higher than in the other two. At the genus level, Saccharopolyspora, Bacillus, Lentibacillus, Staphylococcus, Kroppenstedtia, and Thermoactinomyces were the primary bacterial groups in the sesame-flavored liquor, while Thermomyces, Thermoascus, and Aspergillus represented the main fungal groups. In sample B, the dominant bacteria were Thermoactinomyces, Saccharopolyspora, and Pseudomonas. In the White sample (sample W), Thermoactinomyces was the most abundant, followed by Saccharopolyspora and Lentibacillus. Staphylococcus dominated in the Yellow sample (sample Y), followed by Bacillus and Kroppenstedtia. Regarding the fungi in the three samples, Thermomyces accounted for 93.70% in sample B, and Aspergillus dominated in sample W, while the Thermoascus and Aspergillus content were similar in the sample Y. This study examined the microbial diversity in liquor Daqu with different sesame flavors, providing a foundation for microbial regulation, while investigating the relationship between flavored liquor compounds and microorganisms.