Search Results (81)

Rice wine is a beverage rich in flavor, but the flavor difference caused by rice raw materials has received little attention. To determine the key aroma compounds in rice wine, four types of samples were analyzed by gas chromatography–mass spectrometry (GC–MS), gas chromatography–olfactometry (GC-O), and sensory evaluation. Thirty-eight aroma compounds were detected in the experiment, thirteen of which were identified and quantified using the internal standard method. Additionally, multivariate statistical analyses such as partial least squares discriminant analysis (PLS-DA) effectively revealed three major differential aroma components in rice wine (VIP value ≥ 1). Furthermore, by correlation analysis, it was found that starch and fat in the raw material properties of glutinous rice were significantly and positively correlated with the main differential volatile aroma components in rice wine (p < 0.05). Combined with principal component analysis (PCA), the selection of glutinous rice varieties associated with starch and lipid characteristics during the rice wine brewing process is conducive to improving the overall quality of rice wine. Full article

The study aimed to identify potential sources of novel probiotic yeasts exhibiting health-promoting properties. A combination of metabarcoding analysis and cultural methods was employed to investigate and isolate yeasts from various sources, including rice wine, palm wine, fermented shrimp paste at different stages of natural fermentation, and lychee peels. The two analytical methods revealed distinct yeast profiles, and each source exhibited a unique composition of yeast species. Through metabarcoding and cultural methods, it was demonstrated that lychee peels harbored a greater diversity of genera compared to other sources. The evaluation of the probiotic properties of yeasts revealed that lychee peel yielded the highest proportion of isolates with potential probiotic activity (53.33%), followed by palm wine (25%), fermented shrimp paste (10%), and rice wine (9.09%). Moreover, yeast isolates with health-promoting properties as evaluated in this study, including Starmerella meliponinorum L12 and Pichia terricola L9 from lychee peels, demonstrated notable antioxidant activity and cholesterol-reducing properties, respectively. These findings represent the first report providing initial insights into the influence of yeast sources and serve as a guideline for the targeted selection of yeasts with specific probiotic and health-promoting attributes. Full article

Rice wine, as a traditional fermented beverage, has its quality and flavor influenced by a combination of multiple factors. This review provides an overview of the key aspects of rice wine production, including raw material selection and processing, the regulation of quality by brewing techniques, the mechanisms of microbial community interaction during fermentation, and the types and formation mechanisms of major compounds in rice wine (including flavor compounds and non-volatile components). The study highlights that different raw materials and processing methods significantly impact the fundamental flavor profile of rice wine, while fermentation conditions and dynamic changes in microbial communities determine its flavor complexity and stability. Additionally, this review examines various factors affecting the quality and flavor of rice wine, such as fermentation environment, microbial metabolism, and control of harmful substances, and summarizes modern research and technological advancements, emphasizing the potential of digital and intelligent technologies in enhancing the quality and safety of rice wine. Finally, future research directions are proposed to promote modernization and quality improvement of the rice wine industry. Full article

Vibrio species are among the primary pathogenic bacteria affecting abalone aquaculture, posing significant threats to farming practices. Current clinical control predominantly relies on antibiotics, which can result in antibiotic residues in both abalone and the surrounding marine environments. Lactobacillus plantarum (LP) has been shown to release bioactive antagonistic substances and exhibits potent inhibitory effects against marine pathogenic bacteria. This study aimed to screen and characterize the probiotic properties of LP strains isolated from rice wine lees to develop a novel biocontrol strategy against Vibriosis in abalone. The methods employed included selective media cultivation, streak plate isolation, and single-colony purification for strain screening, followed by Gram staining, 16S rDNA sequencing, and phylogenetic tree construction using MEGA11 for identification. The resilience, antimicrobial activity, and in vivo antagonistic efficacy of the strains were evaluated through stress tolerance assays, agar diffusion tests, and animal experiments. The results demonstrated the successful isolation and purification of four LP strains (NDMJ-1 to NDMJ-4). Phylogenetic analysis revealed closer genetic relationships between NDMJ-3 and NDMJ-4, while NDMJ-1 and NDMJ-2 were found to be more distantly related. All strains exhibited γ-hemolytic activity, bile salt tolerance (0.3–3.0%), and resistance to both acid (pH 2.5) and alkali (pH 8.5), although they were temperature sensitive (inactivated above 45 °C). The strains showed susceptibility to most of the 20 tested antibiotics, with marked variations in hydrophobicity (1.91–93.15%) and auto-aggregation (13.29–60.63%). In vitro antibacterial assays revealed that cell-free supernatants of the strains significantly inhibited Vibrio parahaemolyticus, V. alginolyticus, and V. natriegens, with NDMJ-4 displaying the strongest inhibitory activity. In vivo experiments confirmed that NDMJ-4 significantly reduced mortality in abalone infected with V. parahaemolyticus. In conclusion, the LP strains isolated from rice wine lees (NDMJ-1 to NDMJ-4) possess robust stress resistance, adhesion capabilities, and broad antibiotic susceptibility. Their metabolites exhibit significant inhibition against abalone-pathogenic Vibrios, particularly NDMJ-4, which demonstrates exceptional potential as a candidate strain for developing eco-friendly biocontrol agents against Vibriosis in abalone aquaculture. Full article

In our previous study, when Levilactobacillus brevis FB215, derived from blue cheese, was cultured in a water extract of Sakekasu, a byproduct of brewing Japanese rice wine, putrescine, a polyamine that has been reported to have health-promoting effects, accumulated. However, the culture supernatant exhibited an undesirable taste. A metabolome analysis revealed that the major metabolites that were increased by the fermentation of Sakekasu extract were lactate, citrulline, and putrescine. Sakekasu extract fermented by FB215 and cultured at 20 °C, 25 °C, 30 °C, and 37 °C contained lactate at concentrations of 35, 49, 58, and 59 mM, respectively, while the putrescine concentrations were approximately 1 mM at all culturing temperatures. Furthermore, 500 mL of Sakekasu extract fermented by FB215 contained 0.02 and 2.2% of the acceptable daily intake of tyramine and histamine, respectively, which are biogenic amines that raise safety concerns regarding their use in fermented foods. Supplementation with sucrose at a final sugar concentration of 16% (w/v) significantly improved the overall palatability of the Sakekasu extract fermented by FB215 to a level statistically equivalent to that of commercially available sugar-sweetened lactic acid bacterial beverages. A daily intake of 500 mL of Sakekasu extract fermented by FB215 provided approximately 28 mg of polyamines, which is equivalent to the increase in blood polyamine concentrations reported in a previous study. Full article

Yellow rice wine is susceptible to aflatoxinB₁ (AFB₁) contamination, yet existing detection technologies suffer from limitations such as high false-positive rates, cumbersome operational protocols, or elevated costs, rendering them inadequate for large-scale screening requirements. Consequently, the development of a highly sensitive and rapid detection method for AFB₁ is urgently needed to provide technical support for quality supervision and risk assessment of yellow rice wine. In this study, AFB₁ detection was performed using time-resolved fluorescence immunoassay technology, with quantitative analysis based on the ratio of the T signal value of the detection line to the C signal value of the quality control line and the natural logarithmic value of the standard solution concentration. Statistical experimental designs were used to optimize the process of this rapid detection of AFB₁ in yellow rice wine. The most important factors influencing recovery rate (p < 0.05), as identified by a two-level Plackett-Burman design with 11 variables, were methanol-water volume fraction, sample to extraction solvent ratio, heating temperature, and heating time. The steepest ascent method was employed to identify the optimal regions for these four key factors. Central composite design (CCD) coupled with response surface methodology (RSM) was subsequently utilized to further explore the interactive effects among variables and determine their optimal values that maximize the recovery rate. The analysis results indicated that interactions between methanol-water volume fraction and other three factors–sample to extraction solvent ratio, heating temperature, heating time–affected the response variable (recovery rate) significantly. The predicted results showed that the maximum recovery rate of AFB₁ (97.35%) could be obtained under the optimum conditions of a methanol-water volume fraction of 78%, a sample to extraction solvent ratio of 1:3.2, a heating temperature of 34 °C, and a heating time of 6.4 min. These predicted values were further verified by validation experiments. The excellent correlation between predicted and experimental values confirmed the validity and practicability of this statistical optimum strategy. Optimal conditions obtained in this experiment laid a good foundation for further use of time-resolved fluorescence immunoassay for rapid detection of AFB₁ in yellow rice wine, demonstrating broad application prospects. Full article

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

This study aimed to improve the quality of sweet rice wine through exogenous addition of rice bran and extrusion. The effects of directly fermenting brown rice and adding rice bran on key quality indicators including alcohol content, sugar-to-acid ratio, antioxidant properties, and sensory characteristics were evaluated. Compared to direct fermentation, the exogenous addition of rice bran significantly improved overall wine quality, with 4% rice bran yielding the optimal alcohol content of 1.6% vol and sugar-to-acid ratio exceeding 40. Extrusion modified the physical structure of rice bran, improving its performance as a fermentation substrate. Consequently, both the antioxidant activity and flavor profile of the sweet rice wine were further enhanced. These findings provide valuable theoretical insights for the development of high-quality whole-grain foods. Full article

Huangjiu is a traditional alcoholic beverage in China, but because of the differences in fermentation conditions and raw materials, how to optimize the flavor quality of Huangjiu is facing challenges. This study used high-throughput sequencing (HTS) to investigate microbial diversity in Huangjiu brewed from glutinous rice from five regions in China. Metabolic pathway annotation, electronic senses, and metabolite analysis elucidated the relationships between rice variety, microbial communities, flavor profiles, and metabolic characteristics of Huangjiu. Statistically significant differences in microbial community structure and flavor profiles were observed across Huangjiu samples (p < 0.05), with ten dominant microbial genera identified. Lactic acid bacteria (LAB) enriched in Guizhou and Hubei were positively correlated with higher organic acid (12.36 and 12.30 mg/mL, respectively) and lower amino acid levels (2985 and 2920 mg/L, respectively), contributing to a more pronounced sourness in these Huangjiu. Conversely, Huangjiu from Zhejiang, Guangxi, and Jilin exhibited higher concentrations of Saccharopolyspora, Saccharomonospora, Saccharomyces, and Bacillus, associated with elevated amino acid (3706, 3695, and 3700 mg/L, respectively) and reduced organic acid levels (10.11, 9.92 and 10.10 mg/mL, respectively), resulting in sweetness and bitterness. These findings provide valuable insights for optimizing Huangjiu flavor and quality through targeted microbial and fermentation management. Full article

As a traditional rice wine, sweet fermented rice (SFR) is widely loved because of its unique flavor and high nutritional value. However, the physicochemical properties, microbial community composition, and metabolic pathway changes during the fermentation process of sweet wine have not been evaluated, and these changes can lead to unstable SFR quality. In this study, we used high-throughput sequencing technology to analyze and elucidate the dynamic changes in the microbial community, metabolic pathways, and carbohydrate enzyme functions in traditional SFR fermentation broth. The results revealed that Rhizopus abundance = 160,943.659 and Wickerhamomyces abundance = 241,660.954 were the predominant fungal genera in the fermentation process from the beginning (A0) to the end (A43) of SFR fermentation. The results of the diversity analysis revealed that the structure and composition of the microbial communities first increased but then decreased. Metabolic pathway analysis showed that energy production and conversion, carbohydrate transport, and amino acid transport were the most active metabolic pathways in fermentation. Moreover, the three primary functions of glycosyltransferases (GTs), glycoside hydrolases (GHs), and carbohydrate-binding modules (CBMs) in carbohydrate enzyme analysis were involved in the whole fermentation process. This study only provides some insight into the dynamic changes in the microbial population of SFR single samples prepared under fixed conditions. It provides a reference for optimizing the physicochemical properties of SFR fermentation broth, controlling the microbial community structure, optimizing fermentation conditions, and improving product quality. Full article

As a probiotic strain isolated from Hongqu rice wine (a traditional Chinese fermented food), Limosilactobacillus fermentum FZU501 (designated as Lf) demonstrates exceptional gastric acid and bile salt tolerance, showing potential application as a functional food. The aim of this study was to investigate the protective effect of dietary Lf intervention on alcohol-induced liver injury (ALI) in mice. The results demonstrated that oral administration of Lf effectively ameliorated alcohol-induced lipid metabolism disorders by reducing the serum levels of TC, TG and LDL-C and increasing the serum levels of HDL-C. In addition, oral administration of Lf effectively prevented alcohol-induced liver damage by increasing the hepatic activities of antioxidant enzymes (CAT, SOD, GSH-Px) and alcohol-metabolizing enzymes (ADH and ALDH). Interestingly, 16S amplicon sequencing showed that oral administration of Lf increased the number of Prevotella, Lachnospiraceae_NK4A136_group and Lactobacillus, but decreased the proportion of Faecalibaculum, Adlercreutzia and Alistipes in the intestines of mice that consumed excessive alcohol, which was highly associated with improved liver function. As revealed by liver untargeted metabolomics studies, oral Lf clearly changed liver metabolic profiles, with the signature biomarkers mainly involving purine metabolism, taurine metabolism, tryptophan, alanine, aspartic acid and glutamate metabolism, etc. Additionally, Lf intervention regulated liver gene transcription in over-drinking mice for cholesterol metabolism, bile acid metabolism, fatty acid β-oxidation, alcohol metabolism and oxidative stress. Taken together, the above research results provide solid scientific support for the biological activity of Lf in ameliorating alcohol-induced liver metabolism disorder and intestinal microbiota imbalance. Full article

Foodborne diseases are a growing public health problem worldwide, and chemical foodborne disease outbreaks (FBDOs) often have serious consequences. This study aimed to explore the epidemiological characteristics of chemical FBDOs in Zhejiang Province, China, and propose targeted prevention and control measures. Descriptive statistical methods were used to analyze chemical FBDO data collected from the Foodborne Disease Outbreaks Surveillance System in Zhejiang Province from 2011 to 2023. From 2011 to 2023, 74 chemical FBDOs were reported in Zhejiang Province, resulting in 461 cases, 209 hospitalizations, and one death. In contrast to other types of FBDOs, the percentage of hospitalized cases in chemical FBDOs was the highest (45.34%) (chi-square = 1047.9, p < 0.001). Outbreaks caused by nitrite accounted for the largest percentage (56.76%), followed by lead (17.57%). Outbreaks caused by nitrite occurred mainly in households (27), followed by restaurants (6), street stalls (5), and work canteens (3). Among all nitrite-related outbreaks, 59.52% (25/42) were caused by cooking food where it was used as a common seasoning, 26.19% (11/42) by eating pickled vegetables, 7.14% (3/42) by eating cooked meat products, and 4.76% (2/42) by eating grain products. Outbreaks caused by the misuse of nitrite in cooking mainly occurred in households (68%, 17/25), street stalls (16%, 4/25), work canteens (8%, 2/25), and restaurants (8%, 2/25). Outbreaks caused by eating pickled vegetables occurred mainly in households (90.91%, 10/11), and one outbreak occurred in a work canteen. Outbreaks caused by lead (n = 13) occurred in households, and liquor was involved in 12 outbreaks where they were caused by residents consuming yellow rice wine stored in tin pots. In view of the frequent outbreaks of chemical foodborne diseases in our province from 2011 to 2023, a variety of prevention and control measures were proposed based on the research results of the temporal and regional distribution, food and food establishments involved, and the etiological agents of the chemical FBDOs. However, the effectiveness of these recommendations needs to be further verified and studied. In general, public health institutions should further strengthen the surveillance and health education of the population. Individuals should store toxic chemicals, such as nitrates, pesticides, and rodenticides correctly to avoid poisoning by ingestion. In view of the chemical FBDOs caused by food in the catering and distribution links, relevant departments should strengthen targeted supervision. Full article

Seventy-eight autochthonous strains of Rhizopus arrhizus were isolated from rice wine starter samples across twenty-nine regions in China to evaluate their potential in traditional rice wine fermentation. Strains were assessed for enzyme activity, antioxidant properties, amino acid production, and volatile flavour compounds. Significant variation in enzyme activities was observed, with acidic protease activity ranging from 280 to 1023 U/g, amylase from 557 to 1681 U/g, and esterase from 370 to 2949 U/g. Strains W17 and W42 exhibited the highest enzyme activities and antioxidant capacities, with a total phenolic content of 828 mg/L, total flavonoids of 215 μg/L, and an ABTS scavenging rate of 96.3%. They also produced high levels of glutamic acid (up to 3083 mg/L), enhancing the flavour profile. Histamine levels were low, ranging from 8 to 205 μg/L, ensuring product safety. Analysis of volatile compounds identified 80 substances, including 16 key aroma-active compounds, contributing to a complex flavour profile. These results provide a basis for selecting R. arrhizus strains to optimise rice wine fermentation, addressing market demand for diverse and functional products. Full article

Fumonisins, a class of mycotoxins predominantly produced by Fusarium species, represent a major threat to food safety and public health due to their widespread occurrence in staple crops including peanuts, wine, rice, sorghum, and mainly in maize and maize-based food and feed products. Although fumonisins occur in different groups, the fumonisin B series, particularly fumonisin B1 (FB1) and fumonisin B2 (FB2), are the most prevalent and toxic in this group of mycotoxins and are of public health significance due to the many debilitating human and animal diseases and mycotoxicosis they cause and their classification as by the International Agency for Research on Cancer (IARC) as a class 2B carcinogen (probable human carcinogen). This has made them one of the most regulated mycotoxins, with stringent regulatory limits on their levels in food and feeds destined for human and animal consumption, especially maize and maize-based products. Numerous countries have regulations on levels of fumonisins in foods and feeds that are intended to protect human and animal health. However, there are still gaps in knowledge, especially with regards to the molecular mechanisms underlying fumonisin-induced toxicity and their full impact on human health. Detection of fumonisins has been advanced through various methods, with immunological approaches such as Enzyme-Linked Immuno-Sorbent Assay (ELISA) and lateral flow immunoassays being widely used for their simplicity and adaptability. However, these methods face challenges such as cross-reactivity and matrix interference, necessitating the need for continued development of more sensitive and specific detection techniques. Chromatographic methods, including HPLC-FLD, are also employed in fumonisin analysis but require meticulous sample preparation and derivitization due to the low UV absorbance of fumonisins. This review provides a comprehensive overview of the fumonisin family, focusing on their biosynthesis, occurrence, toxicological effects, and levels of contamination found in foods and the factors affecting their presence. It also critically evaluates the current methods for fumonisin detection and quantification, including chromatographic techniques and immunological approaches such as ELISA and lateral flow immunoassays, highlighting the challenges associated with fumonisin detection in complex food matrices and emphasizing the need for more sensitive, rapid, and cost-effective detection methods. Full article

Enzymatic degradation of the carcinogen ethyl carbamate (EC) and its precursor urea is a promising method for controlling EC levels in alcoholic beverages. However, limited enzymes with EC-hydrolyzing activity and low ethanol or acid tolerance hinder their practical application. Here, a new urease with urea- and EC-hydrolyzing activities from Providencia sp. LBBE was characterized. The enzyme displayed considerable ethanol tolerance, retaining 42.4% activity after 1 h of incubation with 30% (v/v) ethanol at 37 °C. It exhibited broad pH tolerance (pH 3.0–8.0), with optimal pH 7.0 for EC and 7.5 for urea. After treatment at pH 4.5 and 5.0, it retained 41.3% and 59.4% activity, respectively. The K_m and V_max for EC and urea at pH 4.5 were 515.6 mM, 33.9 µmol/(min⸱mg) and 32.0 mM, 263.6 µmol/(min⸱mg), respectively. Using 6000 U/L purified enzyme at 30 °C for 9 h, 49.8% and 81.6% of urea was removed from rice wine (pH 4.5 and 7.0), respectively. No appreciable reduction in EC was observed under identical conditions, which may be ascribed to the minimal EC affinity. This study contributes to the future realization of the effective control of EC content in alcoholic beverages. Full article