Variation and fractionation of δ2H, δ18O, and δ17O stable isotopes from irrigation water to soil, grapes, and wine for the traceability of geographical origins.

To investigate the variation and fractionation of stable isotopes from irrigation water to soil, grapes, and wine, δ2H, δ18O, and δ17O in different samples from 10 regions in China were determined using a water isotope analyser. The values were significantly different among regions according to the chemometric analysis. All isotopes were significantly and positively correlated with irrigation water-soil and grape-wine. A significant water isotopic fractionation effect was observed from the irrigation water to the soil, grapes, and wine. Stable isotope distribution characteristics correlated with longitude, latitude, altitude, temperature, precipitation, station pressure and wind speed. The linear discriminant analysis (LDA), random forest (RF), support vector machine (SVM), and feed-forward neural network (FNN) models 58.33-100 %, 80-100 %, 53.33-100 %, and 73.33-100 % accurate for distinguishing the geographical origins of all samples from training and test data, respectively. These findings provide a theoretical basis for authenticating the geographic origin of Chinese wines using stable isotope analysis.

Mechanism of Polygonum hydropiper reducing ethyl carbamate in Chinese rice wine (Huangjiu) brewing.

Polygonum hydropiper (PH) is a rich source of active compounds and serves as a pivotal ingredient in Chinese rice wine (Huangjiu) production. This study investigates the impact of PH and Polygonum hydropiper extract (PHE) on ethyl carbamate (EC) production during Huangjiu fermentation. Our findings reveal that PH enhances the relative abundance of Bacillus subtilis in Huangjiu fermentation, thereby facilitating its interaction with Saccharomyces cerevisiae. Furthermore, PH modulates the urea metabolism of S. cerevisiae. In the PH-B. subtilis-S. cerevisiae fermentation system, the expression of DUR1,2 and DUR3 genes in S. cerevisiae is upregulated. This augmentation leads to increased urea uptake and metabolism by S. cerevisiae in the fermentation broth, subsequently reducing the urea concentration in the fermentation medium (The EC content in the CK group was approximately 355.55 % and 356.05 % higher than those in the PH and PHE groups, respectively). Consequently, PH demonstrates promise in reducing the EC concentration of Huangjiu, offering a novel approach to enhance the safety of Huangjiu consumption.

Enhancing nutritional composition and aroma characteristics of kiwifruit wines through indigenous non-Saccharomyces yeast extracellular extract treatment.

To unlock the potential of strains for further enhancing the aromatic complexity of kiwifruit wines while avoiding undesirable flavors, indigenous non-Saccharomyces yeast extracellular extract treatment for fermentation was established. The extracellular extract from Zygosaccharomyces rouxii, Pichia kudriavzevii, and Meyerozyma guilliermondii were prepared and supplemented individually or in pairs to the kiwifruit wine fermentation system. Subsequently, the changes in physicochemical properties, antioxidants, and volatile characteristics of kiwifruit wines produced by different protocols were comprehensively evaluated, and the major aroma descriptors affecting sensory acceptability were analyzed by sensory evaluation and partial least squares regression. The results showed that extracellular extract treatment significantly improved the organic acids and monomeric phenols content, antioxidant capacity, and volatiles of kiwifruit wines. Compared to Sc, the increase in esters and alcohols, along with the decrease in aldehydes and acids in Pk-Zr and Mg-Zr, enhanced the aromatic complexity while reduce grassy and fungal flavors, resulting in higher sensory acceptability.

Metagenomics reveals the differences in flavor quality of rice wines with Hongqu and Maiqu as the fermentation starters.

Chinese rice wine (CRW) is an alcoholic beverage made mainly from rice or grain through saccharification and fermentation with Jiuqu (starter). Jiuqu makes an important contribution to the formation of the flavor characteristics of rice wine. Hongqu and Maiqu are two kinds of Jiuqu commonly used in CRW brewing. This study compared the microbial community, biogenic amines (BAs), and volatile flavor components (VFCs) of two types of rice wine brewed with Hongqu and Maiqu as fermentation agents. The results showed that the amino acid content of rice wine fermented with Maiqu (MQW) was significantly lower than that of rice wine fermented with Hongqu (HQW). On the contrary, the majority of BAs in MQW were significantly higher than those in HQW, except for putrescine. Multivariate statistical analysis indicated that most of the VFCs detected were enriched in HQW, while ethyl 3-phenylpropanoate and citronellol were enriched in MQW. The results of metagenomic analysis showed that Weissiella, Enterobacter, Leuconostoc, Kosakonia, Saccharomyces, Aspergilus and Monascus were identified as the predominant microbial genera in HQW brewing process, while Saccharopolyspora, Lactococcus, Enterobacter, Leuconostoc, Kosakonia, Pediococcus, Pantoea, Saccharomyces, Aspergillus, Lichtheimia and Nakaseomyces were the predominant microbial genera in MQW brewing. In addition, some VFCs and BAs were strongly correlated with dominant microbial genera in HQW and MQW brewing. Bioinformatics analysis showed that the abundance of genes involved in BAs synthesis in MQW brewing was much higher than that in HQW brewing, while the abundances of genes related to metabolic pathway of characteristic VFCs in HQW brewing were obviously higher than those in MQW, which explained the differences in flavor quality between HQW and MQW from the perspective of microbial genes. Collectively, these findings provide scientific evidence for elucidating the contribution of different microbial genera to the formation of flavor quality of CRW, and is helpful for screening beneficial microbes to enhance flavor quality and drinking comfort of CRW.

Multi-omics framework to reveal the molecular determinants of fermentation performance in wine yeast populations.

BACKGROUND: Connecting the composition and function of industrial microbiomes is a major aspiration in microbial biotechnology. Here, we address this question in wine fermentation, a model system where the diversity and functioning of fermenting yeast species are determinant of the flavor and quality of the resulting wines. RESULTS: First, we surveyed yeast communities associated with grape musts collected across wine appellations, revealing the importance of environmental (i.e., biogeography) and anthropic factors (i.e., farming system) in shaping community composition and structure. Then, we assayed the fermenting yeast communities in synthetic grape must under common winemaking conditions. The dominating yeast species defines the fermentation performance and metabolite profile of the resulting wines, and it is determined by the initial fungal community composition rather than the imposed fermentation conditions. Yeast dominance also had a more pronounced impact on wine meta-transcriptome than fermentation conditions. We unveiled yeast-specific transcriptomic profiles, leveraging different molecular functioning strategies in wine fermentation environments. We further studied the orthologs responsible for metabolite production, revealing modules associated with the dominance of specific yeast species. This emphasizes the unique contributions of yeast species to wine flavor, here summarized in an array of orthologs that defines the individual contribution of yeast species to wine ecosystem functioning. CONCLUSIONS: Our study bridges the gap between yeast community composition and wine metabolite production, providing insights to harness diverse yeast functionalities with the final aim to producing tailored high-quality wines. Video Abstract.

Isolation, identification, and technological characteristics analysis of yeast strains from Pyracantha fortuneana fruits fermentation liquid.

Pyracantha fortuneana (P. fortuneana), as a medicinal and edible plant resource, is rich in nutrients. In order to screen the high quality yeast used in Firebone fruit wine, 12 strains of yeast were isolated and purified from P. fortuneana fermentation broth by traditional pure culture method. They were identified by molecular biology as Pichia kudriavzevii (P. kudriavzevii) and Saccharomyces cerevisiae (S. cerevisiae), respectively. Strain HJ-2 could grow normally at 30℃, alcohol content 15%, SO2 mass concentration 360 mg/L, pH 3.2, sucrose mass concentration 400 g/L and glucose mass concentration 250 g/L. Strain HJ-6 could grow normally at 30℃, alcohol content 3%, SO2 concentration 360 mg/L, pH 3.2, sucrose concentration 250 g/L, glucose concentration 300 g/L. Based on the technological characteristics of fruit wine, S. cerevisiae HJ-2 has the potential of brewing P. fortuneana fruit wine. P. kudriavzevii HJ-6 has a low tolerance to ethanol and is suitable for the production of fermented beverages such as low-alcohol wine or beer.

Isolation and identification of epiphytic Pichia kudriavzevii from loquat peels and investigation of its fermentation characteristics for liquor production.

During the process of fruit wine production, yeast plays a crucial role in influencing the taste, flavor, and overall quality of the wine. This study aims to enhance the flavor and quality of loquat wine by isolating strains of Pichia kudriavzevii (P. kudriavzevii) with desirable winemaking characteristics from loquat fruit fermentation broth. A total of 12 strains of P. kudriavzevii were isolated and subjected to morphological and molecular biological identification. Their fermentation performance, ethanol production, ester production, hydrogen sulfide production, killer activity, and tolerance were evaluated. The results revealed that strains Q-2, Q-9, Q-10, Q-12, Q-20, and Q-42 exhibited robust growth and strong tolerance under conditions of 40 °C temperature, 12% ethanol concentration, 350 g/L glucose concentration, and pH 2.8. Strain Q-42 demonstrated the strongest gas production capacity, killer activity, and good ester and ethanol production. As a highly active fermentation strain with excellent wine making characteristics, P. kudriavzevii Q-42 provides a valuable yeast resource for the industrial production of loquat wine and offers technical support for improving the overall quality of loquat wine.

The Use of Ultra-Fast Gas Chromatography for Fingerprinting-Based Classification of Zweigelt and Rondo Wines with Regard to Grape Variety and Type of Malolactic Fermentation Combined with Greenness and Practicality Assessment.

In food authentication, it is important to compare different analytical procedures and select the best method. The aim of this study was to determine the fingerprints of Zweigelt and Rondo wines through headspace analysis using ultra-fast gas chromatography (ultra-fast GC) and to compare the effectiveness of this approach at classifying wines based on grape variety and type of malolactic fermentation (MLF) as well as its greenness and practicality with three other chromatographic methods such as headspace solid-phase microextraction/gas chromatography-mass spectrometry with carboxen-polydimethylosiloxane fiber (SPME/GC-MS with CAR/PDMS fiber), headspace solid-phase microextraction/gas chromatography-mass spectrometry with polyacrylate fiber (SPME/GC-MS with PA fiber), and ultra performance liquid chromatography-photodiode array detector-tandem mass spectrometry (UPLC-PDA-MS/MS). Principal Component Analysis (PCA) revealed that fingerprints obtained using all four chromatographic methods were suitable for classification using machine learning (ML). Random Forest (RF) and Support Vector Machines (SVM) yielded accuracies of at least 99% in the varietal classification of Zweigelt and Rondo wines and therefore proved suitable for robust fingerprinting-based Quality Assurance/Quality Control (QA/QC) procedures. In the case of wine classification by the type of MLF, the classifiers performed slightly worse, with the poorest accuracy of 91% for SVM and SPME/GC-MS with CAR/PDMS fiber, and no less than 93% for the other methods. Ultra-fast GC is the greenest and UPLC-PDA-MS/MS is the most practical of the four chromatographic methods.

Comparison of Flavor Differences between the Juices and Wines of Four Strawberry Cultivars Using Two-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry and Sensory Evaluation.

Fruit wine production is a practical approach for extending the shelf life and enhancing the value of strawberries (Fragaria × ananassa). Fruit cultivars and juices are important sources of volatile organic compounds (VOCs) that determine fruit wine sensory quality. In this study, VOCs in the juices and wines of four strawberry cultivars were identified using two-dimensional gas chromatography-time-of-flight mass spectrometry, and a sensory analysis of the wines was performed. A total of 1028 VOCs were detected. PCA and OPLS-DA distinguished the four cultivars from which the juices and wines were made. Six VOCs with variable importance in projection values greater than one were the main aroma and flavor components of strawberry wines. ZJ wine had the highest sensory scores for coordination (9.0) and overall evaluation (8.9) among the 18 descriptors of strawberry wine evaluated. Overall, the ZJ wine had the highest alcohol content (13.25 ± 0.59%, v/v) and sensory evaluation score, indicating that the ZJ cultivar is more suitable for fermentation. This study reflects the differences between wines made from four strawberry cultivars and provides a reference for brewing fruit wines.

Regional aroma characteristics of spontaneously fermented Cabernet Sauvignon wines produced from seven sub-regions in Shangri-La of China.

Shangri-La is a promising wine region in China, which has great potential for producing high-quality wines with distinctive regional characteristics. In this work, the aroma properties of spontaneously fermented Cabernet Sauvignon wines produced from seven sub-regions of Shangri-La (Adong, Liutongjiang, Sinong, Xidang, and Nitong from Lancang River basin; Benzilan and Dari from Jinsha River Basin) were comprehensively analyzed using the headspace micro-extraction with gas chromatography-mass spectrometry, odor activity values, and olfactory evaluation. Results showed that a total of 59 volatiles belonging to seven groups were identified and quantified in all regional wines, with alcohols constituting the most abundant group, followed by esters and volatile fatty acids. Based on their odor activity values, six alcohols, seven esters, two terpenes, one C13-norisoprenoids, and three volatile fatty acids were identified as key volatiles which significantly contribute to the aroma of these wines. Principal component analysis showed the distinct compositions of these 19 key volatiles among the seven regional wines. Olfactory evaluation revealed certain differences in aroma profiles, particularly "Tropical fruit", "Dried fruit", "Vegetal", and "Sweet" among them. This study enhances our understanding on the unique terroir flavors of Shangri-La wines and is helpful for further producing high-quality wines with regional characteristics.

The Potential Effects of Red Wine and Its Components on Neurocognitive Disorders: A Narrative Review.

BACKGROUND: The aging population is associated with a net increase in the incidence and prevalence of chronic-degenerative diseases, particularly neurocognitive disorders. Therefore, the identification of preventative strategies to restrain the burden of such chronic conditions is of key relevance. Red wine and its components have accumulated evidence regarding their positive effects in terms of neurological pathologies associated with neurocognitive symptoms. METHODS: Based on this background, the present narrative review aims to summarize the state-of-the-art evidence on the effects of red wine and its components on neurocognitive disorders in both preclinical and clinical settings. RESULTS: The main findings highlight a protective effect of wine polyphenols present in red wine on dementia in different preclinical models of cognitive decline. The current translational clinical evidence remains uncertain, especially considering the risk-to-benefit ratio of alcohol consumption on brain health. CONCLUSIONS: Given the overall health risks associated with red wine consumption and consistent with the prevailing guidelines in the literature, there is insufficient evidence to support light-to-moderate red wine consumption as an effective strategy for preventing these diseases. However, the largely preclinical findings on polyphenols derived from red wine remain of significant interest in this context.

Old Wine in New Bottles: The Technological Promise of Biorefinery In Historical Perspective.

Biorefineries are often lauded as revolutionary, sustainable new sources of power. This article critically examines biorefineries from historical and environmentalist perspectives, highlighting flaws such narratives. It proposes an alternative to the biorefinery paradigm that draws on critical environmentalist scholarship, French political ecology and the German tradition of sanfte Chemie (soft chemistry). History, the article argues, is crucial for identifying technological dead ends.

Impact of fermented wine lees on gut microbiota and metabolic responses in Guanling crossbred cattle.

BACKGROUND: The addition of wine lees to diets can make up for the deficiencies caused by traditional forages in beef cattle farming. However, the effects of different wine lees ratios on average daily weight, gastrointestinal microbial community structure and metabolites in Guanling crossbred cattle have been rarely studied. This study assessed the effects of feeds containing wine lees on weight gain, gastrointestinal microbial community structure, and metabolites in Guanling crossbred cattle and elucidated the metabolic responses induced by wine lees. Eighteen cows were randomly assigned to receive fed concentrate (C group), feed containing 15% wine lees (group A), or feed containing 30% wine lees (group B) for 60 days. RESULTS: The average daily weight gain of group A and group B increased by 76.75% and 57.65%, respectively, compared with group C. Microbial community analysis showed that wine lees increased the abundance of Prevotella_1 in the rumen, decreased the abundance of Ruminococcaceae UCG 011 and Lachnospiraceae_FCS020_group in the rumen, and increased the abundance of Tyzzerella_4, Family_Xlll_AD3011_group, Granulicella, and Eisenbergiella in the cecum. Metabolomics analyses showed that wine lees decreased the concentrations of indole-3-ethanol in the rumen, and complexity cecal metabolism. Notably, linoleic acid metabolism was significantly enriched in both the rumen and cecum. Mantel test analyses indicated that the adverse effects of WL were reduced by stimulating the metabolism of linoleic acid, α-linolenic acid, and tryptophan, and these changes were mediated by intestinal microorganisms. The Guanling cattle cecum was enriched for several unfavorable metabolic pathways when wine lees concentrations reached 30%, which increased the likelihood of intestinal lesions. CONCLUSION: This study shows that WL supplementation alters gut microbiota and metabolic pathways, improving cattle growth and health. Moderate WL levels (15%) enhance gut health and beneficial pathways (e.g., linoleic and alpha-linolenic acid metabolism). However, higher WL inclusion (30%) may activate adverse pathways, raising the risk of intestinal damage. To maximize benefits and minimize risks, WL levels should be carefully managed.

Exploring fermentative metabolic response to varying exogenous supplies of redox cofactor precursors in selected wine yeast species.

The use of non-Saccharomyces yeasts in winemaking is gaining traction due to their specific phenotypes of technological interest, including their unique profile of central carbon metabolites and volatile compounds. However, the lack of knowledge about their physiology hinders their industrial exploitation. The intracellular redox status, involving NAD/NADH and NADP/NADPH cofactors, is a key driver of yeast activity during fermentation, notably directing the formation of metabolites that contribute to the wine bouquet. The biosynthesis of these cofactors can be modulated by the availability of their precursors, nicotinic acid and tryptophan, and their ratio by that of thiamine. In this study, a multifactorial experiment was designed to assess the effects of these three nutrients and their interactions on the metabolic response of various wine yeast species. The data indicated that limiting concentrations of nicotinic acid led to a species-dependent decrease in intracellular NAD(H) concentrations, resulting in variations of fermentation performance and production of metabolic sinks. Thiamine limitation did not directly affect redox cofactor concentrations or balance, but influenced redox management and subsequently the production of metabolites. Overall, this study identified nicotinic acid and thiamine as key factors to consider for species-specific modulation of the metabolic footprint of wine yeasts.

Molecular Insights into the Aroma Difference between Beer and Wine: A Meta-Analysis-Based Sensory Study Using Concentration Leveling Tests.

Beer and wine are popular beverages with clearly different aroma characters, the molecular background of which has not yet been systematically investigated. A comprehensive literature survey returned 14 845 concentration values obtained from 160 beer and 904 wine samples, covering 42 basic beer and 42 basic wine odorants, among which 40 were common to both beverages. Based on mean concentrations and a comparison with threshold data, 29 beer and 32 wine odorants were finally selected to build aroma base models that reflected the basic olfactory difference between beer and wine. Orthonasal concentration leveling tests applied to groups of odorants with similar odor characteristics finally revealed the crucial role of fruity smelling compounds. When 11 fruity compounds, predominantly esters, in the beer aroma base model were adjusted to the respective concentration levels in the wine aroma base model, the sensory panel no longer described the sample as beer-like but as wine-like.

Wine, Polyphenols, and the Matrix Effect: Is Alcohol Always the Same?

While the number of publications on wine and health is steadily increasing, ranging from a molecular level to epidemiological studies, often with contradictory results, little attention has been given to a holistic approach to research, starting from the molecular level to arrive at pharmacological and medical conclusions. In this review, some unusual concepts are considered, such as the phytocomplex, the vehicle, and the Matrix effect. The concept of the phytocomplex is discussed, specifically the biological activities of Tyrosol, Hydroxytyrosol, and Resveratrol; indeed, the interactions among different molecules in herbal matrices provide a specific response. This is often markedly different from the response evoked by single constituents in the modulation of microbial populations in the gut, in intestinal stability and bioaccessibility, and, obviously, in inducing biological responses. Among the many alcoholic beverages which contain these molecules, wine has the most peculiar Matrix effect, which can heavily influence the bioavailability of the phytocomplex obtained by the fermentation processes that produce this beverage. Wine's Matrix effect plays an instrumental role in improving the beneficial compounds' bioavailability and/or in inhibiting alcohol metabolites' carcinogenicity. Underestimation of the wine Matrix effect could lead to deceiving results, as in the case of dealcoholized wine or wine-compound-based nutritional supplements; alternatively, this can occur in the emphasis of a single component's toxic activity, in this case, alcohol, ignoring the specific molecular-level protective action of other compounds (polyphenols) that are present in the same matrix. The dark side of the Matrix effect is also discussed. This review confirms the research recommendations made by the WHO Scientific Group, which suggests it is important "to investigate the possible protective effects of ingredients other than alcohol in alcoholic beverages", considering that most recent studies seem not only relevant but also capable of directing future research towards innovative points of view that have so far been too neglected.

A New Approach for CRISPR/Cas9 Editing and Selection of Pathogen-Resistant Plant Cells of Wine Grape cv. 'Merlot'.

Grape is one of the most economically significant berry crops. Owing to the biological characteristics of grapes, such as the long juvenile period (5-8 years), high degree of genome heterozygosity, and the frequent occurrence of inbreeding depression, homozygosity during crossbreeding leads to loss of varietal characteristics and viability. CRISPR/Cas editing has become the tool of choice for improving elite technical grape varieties. This study provides the first evidence of a decrease in the total fraction of phenolic compounds and an increase in the concentration of peroxide compounds in grape callus cells upon the addition of chitosan to the culture medium. These previously unreported metabolic features of the grape response to chitosan have been described and used for the first time to increase the probability of selecting plant cells with MLO7 knockout characterised by an oxidative burst in response to the presence of a pathogen modulated by chitosan in the high-metabolite black grape variety 'Merlot'. This was achieved by using a CRISPR/Cas9 editing vector construction with the peroxide sensor HyPer as a reporter. This research represents the first CRISPR/Cas9 editing of 'Merlot', one of the most economically important elite technical grape varieties.

The Influence of Quercus alba Geographical Location and Aging Time on the Chemical and Sensory Quality of Tempranillo Wines.

The changes produced during the aging of wines in oak barrels are strongly dependent on the oak's geographical origin and aging time. This paper analyzes the effect of Quercus alba oak from four different geographical locations in four states in the USA, namely Missouri (Mo), Ohio (Oh), Kentucky (Kt), and Pennsylvania (Py), during 24 months of aging. Oak origin had a higher effect on the wine's aromatic composition than the polyphenolic one. Mo and Oh barrels enhanced coconut, spicy, and sweet notes for 12 months of aging, while Kt barrels achieved higher extraction of wood-related compounds at longer aging (24 months). Py wines showed the lowest contents of most volatile compounds at both aging times, as well as hydroxycinnamic acids, flavanols, anthocyanins, flavonols, stilbenes, and ellagitannins, attributed to their higher porosity. At 12 months of aging, Kt wines showed the highest content of ellagitannins, and Mo wines had the highest content of anthocyanins, but Oh wines had the highest concentrations at 24 months. In the sensory analysis, Kt wines were preferred at both aging times. Kt and Mo wines achieved the highest punctuations for the olfactory phase at 12 months of aging and Kt wines kept it after 24 months. These findings are essential for producers to achieve the sensory characteristics of their wines through strategic barrel aging.

Seed morphometrics unravels the evolutionary history of grapevine in France.

The cultivation of grapevines has spanned millennia, leading to thousands of varieties through exchanges, mutations, and crosses between genotypes, as well probably as gene flow from wild populations. These varieties are typically categorized by regional origin and primary use, either for wine production or fruit consumption. France, within the Western European group, hosts many of the world's renowned wine grape varieties. However, the historical development of cultivated grapevines in France and in the world remains poorly understood. This study applies morphometry on 19,377 charred and waterlogged archaeological grape pips to investigate the evolutionary history of grapevine in France over the last 10,000 years. The study compares seed outlines and lengths, corrected for taphonomic distortions, with a reference collection of 80 wild and 466 modern domestic grapevine accessions. Findings reveal a shift from wild grapevine exploitation to the expansion of domestic varieties around 600-500 BCE, coinciding with Mediterranean cultural influences and the introduction of eastern grape types. The identification of the East-Table group, a group of varieties of eastern origin for fruit consumption, indicates that grapes were also grown for food, especially in Mediterranean regions and near urban areas, alongside wine production. Early French viticulture featured a notable presence of Western European wine-type grapevines. The abundance of pips with wild-like morphology suggests early cultivation involved plants at an initial domestication stage and gene flow between introduced and wild grapevines. As viticulture spread northward, wild and Eastern morphotypes declined, leading to the dominance of Western European wine types in inner France during the Middle Ages.