Search Results (3)

Hongqujiu, one of the three principal varieties of yellow wine, is a traditional fermented beverage originating from China that employs Hongqu as the fermentation agent. In this study, an untargeted metabolomics approach based on gas chromatography–mass spectrometry (GC-MS) and liquid chromatography–mass spectrometry (LC-MS) was applied to systematically analyze the volatile compounds (VOCs) and non-volatile compounds (NVCs) in Hongqujiu across different aging years for the first time. The analysis identified a total of 262 VOCs and 2564 NVCs in samples of Hongqujiu aged for six distinct years. Based on metabolic differences, the samples were categorized into two groups: the low-year group (5-year, 6-year) and the high-year group (8-year, 10-year, 15-year, 20-year). Nineteen VOCs (e.g., 4-amino-butyric acid and diethanolamine) and thirty NVCs (e.g., palmitoylethanolamide and erinacine D) were identified as key differential metabolites distinguishing the low-year group from the high-year group. The higher-year group is enriched with a variety of substances with different flavors or biological activities, such as sugar derivatives, amino acids and their complexes, organic acids and their intermediate metabolites, steroids and terpenoid compounds, lipids and their derivatives, nitrogen-containing heterocycles, and aromatic compounds. The accumulation of these substances not only shapes the unique and rich flavor characteristics of aged red rice wine (such as the caramel aroma and umami peptide flavor), but also endows red rice wine with potential health benefits due to the physiological regulatory functions of some active ingredients. This study contributes to a deeper understanding of the composition and dynamic variations in metabolites in Hongqujiu, offering a scientific foundation for identifying aged Hongqujiu and conducting further research to enhance its quality. Full article

Hongqu rice wine is a traditional Chinese yellow wine produced from a single ingredient. To enhance the competitiveness of the product and better adapt to market development trends, the development of a complexed Hongqu rice wine using a variety of ingredients is necessary to enhance the nutritional value of the product and diversify its flavor. This study explored production technology for the development of a complexed Hongqu rice wine using kiwiberry as the raw material. The mixed fermentation process was optimized using single-factor experiments and response surface methodology (RSM). The optimal conditions were a juice addition time of 93 h, a fermentation temperature of 31 °C, and a juice addition amount of 75 g/100 g. Under these conditions, the complexed Hongqu rice wine had an alcohol content of 8.7% vol, a total phenolic content of 0.42 mg GAE/mL, and a total flavonoid content of 0.32 mg CE/mL. In total, 27 metabolites were identified. The relative levels of 15 metabolites, including quercetin-3-glucoside and rutin, increased significantly after the adding of the kiwiberry (VIP > 1.0, p < 0.05, FC > 2). Antioxidant activity experiments showed that the Hongqu rice wine had notable antioxidant capacity and that adding the kiwiberry significantly enhanced this capacity. Additionally, the complexed Hongqu rice wine exhibited hypoglycemic and bile acid-binding properties. It achieved 78.68 ± 0.44% inhibition of α-amylase and 58.02 ± 0.50% inhibition of α-glucosidase. The binding activities with sodium glycocholate, sodium cholate, and sodium taurocholate were 40.25 ± 0.64%, 49.08 ± 1.05%, and 60.58 ± 0.80%, respectively. Consequently, a complexed Hongqu rice wine rich in quercetin-3-glucoside and rutin, with notable antioxidant activities, was developed. This wine has potential applications in functional food development. Full article

As one of the typical representatives of Chinese rice wine (Huangjiu), Hongqu rice wine is produced with glutinous rice as the main raw material and Hongqu as the fermentation starter. The complex microbial flora in the brewing process may have a great influence on the formation of the flavor quality and drinking safety of Hongqu rice wine. Previous studies have shown that high biogenic amine (BA) content in rice wine has potential physiological toxicity and has become a bottleneck problem restricting the development of the rice wine industry. This study aimed to evaluate the regulatory effects of the microbial community on the formation of BAs and volatile flavor components during the brewing of Hongqu rice wine. The results demonstrated that histamine, putrescine, cadaverine, tyramine, tryptamine, spermine, and spermidine were the main BAs in Hongqu rice wine. The contents of putrescine, cadaverine, histamine, tyramine, and spermidine in Hongqu rice wine of HBAs (with higher BAs content) were significantly higher than those in LBAs (with lower BAs content). GC-MS testing results showed that there were significant differences in the composition of volatile organic compounds (VOCs) between HBAs and LBAs. Among them, VOCs such as 2-methoxy-4-vinylphenol, ethyl caprate, phenethyl acetate, ethyl lactate, ethyl myristate, ethyl palmitate, ethyl n-octadecanoate, ethyl oleate, and ethyl linoleate were identified as the characteristic volatile components with significant differences between HBAs and LBAs. Microbiome analysis based on metagenomic sequencing revealed that unclassified_g_Pantoea, Klebsiella pneumoniae, Panobacter disperse, unclassified_f_Enterobacteriaceae, Leuconostoc mesenteroides, and Saccharomyces cerevisiae were the dominant microbial species in the HBA brewing process, while Weissella confuse, Pediococcus acidilactici, Saccharomyces cerevisiae, and Aspergillus niger were the dominant microbial species in the LBA brewing process. Furthermore, correlation heatmap analysis demonstrated that BAs were positively related to Lactobacillus curvatus, Lactococcus lactis, and Leuconostoc mesenteroides. Bioinformatical analysis based on the KEGG database revealed that the microbial genes encoding enzymes involved in BAs’ synthesis were more abundant in HBAs, and the abundances of microbial genes encoding enzymes related to BAs’ degradation and the metabolism of characteristic volatile components were higher in LBAs. Overall, this work provides important scientific data for enhancing the flavor quality of Hongqu rice wine and lays a solid foundation for the healthy development of the Hongqu rice wine industry. Full article