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1.
J Sep Sci ; 47(9-10): e2400142, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38726732

RESUMO

Catechins, renowned for their antioxidant properties and health benefits, are commonly present in beverages, particularly tea and wine. An efficient and cost-effective salting-out assisted liquid-liquid extraction (SALLE) method has been developed and validated for the simultaneous determination of six catechins and caffeine in tea and wine samples using high-performance liquid chromatography-ultraviolet (HPLC-UV). This method demonstrates outstanding performance: linearity (1-120 µg/mL, r2 > 0.999), accuracy (96.5%-103.4% recovery), and precision (≤14.7% relative standard deviation), meeting validation requirements set by the US Food and Drug Administration. The reduced sample size (0.1 g) minimizes matrix interferences and costs without compromising sensitivity. All analytes were detected in Camellia sinensis teas, with green tea displaying the highest total catechin content (47.5-100.1 mg/mL), followed by white and black teas. Analysis of wine samples reveals the presence of catechin in all red and white wines, and epigallocatechin gallate in all red wine samples, highlighting the impact of winemaking processes on catechin content. The SALLE-HPLC-UV approach represents a green alternative by eliminating organic waste, surpassing conventional dilution methods in specificity and sensitivity for catechin determination. AGREEprep assessment emphasizes the strengths of the SALLE procedure, including material reusability, throughput efficiency, minimal sample requirements, low energy consumption, and the absence of organic waste generation.


Assuntos
Cafeína , Catequina , Extração Líquido-Líquido , Chá , Vinho , Cromatografia Líquida de Alta Pressão/métodos , Vinho/análise , Cafeína/análise , Catequina/análise , Chá/química , Extração Líquido-Líquido/métodos , Espectrofotometria Ultravioleta , Raios Ultravioleta
2.
Molecules ; 29(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731406

RESUMO

The effects of canopy treatment with chitosan and the effects of the vineyard location on the quality parameters, volatile and non-volatile profiles, and sensory profile of Pinot Noir wines from South Tyrol (Italy) were studied. Multivariate statistical analysis was applied to identify the most relevant compounds associated with the variability in phenolics and anthocyanins (analyzed by UHPLC-MS), volatile components (HS-SPME-GCxGC-ToF/MS), and basic enological parameters. A clear separation of low-altitude wines (350 m.a.s.l.), which had a high concentration of most of the identified volatile compounds, compared to high-altitude wines (800 and 1050-1150 m.a.s.l.) was pointed out. Low altitude minimized the concentration of the most significant anthocyanins in wines from a valley bottom, presumably due to reduced sun exposure. Wines obtained from chitosan-treated canopies, and, more particularly, those subjected to multiple treatments per year showed a higher amount of the main non-volatile phenolics and were sensorially described as having "unpleasant flavors" and "odors", which might suggest that grape metabolism is slightly altered compared to untreated grapevines. Thus, optimization of the treatment with chitosan should be further investigated.


Assuntos
Antocianinas , Quitosana , Fenóis , Vitis , Compostos Orgânicos Voláteis , Vinho , Antocianinas/análise , Quitosana/química , Vinho/análise , Vitis/química , Fenóis/análise , Compostos Orgânicos Voláteis/análise , Itália , Cromatografia Líquida de Alta Pressão
3.
Molecules ; 29(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731535

RESUMO

Pre-fermentation treatment has an important impact on the color, aroma, taste, and other characteristics of fruit wine. To discover suitable pre-treatment techniques and conditions that yield strawberry wine of excellent quality, the influences of juice fermentation, pulp maceration, thermovinification, and enzymatic hydrolysis pre-treatments on the basic chemical composition, color, antioxidant capacity, and volatile organic compounds in strawberry wines were investigated. The results showed that the color, antioxidant properties, and volatile aroma of strawberry wines fermented with juice were different from those with pulp. Strawberry wines fermented from juice after 50 °C maceration had more desirable qualities, such as less methanol content (72.43 ± 2.14 mg/L) compared with pulp-fermented wines (88.16 ± 7.52 mg/L) and enzymatic maceration wines (136.72 ± 11.5 mg/L); higher total phenolic content (21.78%) and total flavonoid content (13.02%); enhanced DPPH (17.36%) and ABTS (27.55%) free radical scavenging activities; richer essential terpenoids and fatty acid ethyl esters, such as linalool (11.28%), ethyl hexanoate (14.41%), ethyl octanoate (17.12%), ethyl decanoate (32.49%), and ethyl 9-decenoate (60.64%); pleasant floral and fruity notes compared with juice-fermented wines macerated at normal temperatures; and a lighter color. Overall, juice thermovinification at 50 °C is a potential pre-treatment technique to enhance the nutrition and aroma of strawberry wine.


Assuntos
Antioxidantes , Fermentação , Fragaria , Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Compostos Orgânicos Voláteis/análise , Fragaria/química , Antioxidantes/análise , Antioxidantes/química , Odorantes/análise , Fenóis/análise , Flavonoides/análise , Frutas/química , Cor
4.
J Agric Food Chem ; 72(19): 11051-11061, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38698723

RESUMO

Multiple analytical methodologies allow quantitation of H2S and methanethiol (MeSH) in wine, but confirmation that the determined concentrations are related to perceived off-aromas, or "reductive" faults, is yet to be provided. Fifty white wines underwent sensory evaluation and measurement of free and salt-treated H2S and MeSH concentrations by gas chromatography with sulfur chemiluminescence detection and/or gas detection tubes. The determined concentrations were compared across techniques and different analysis laboratories. Sulfhydryl off-odors in the wines were best described by boiled and rotten egg and natural gas/sewerage/durian aroma attributes. The wines with the highest ratings for both aromas had high concentrations of free H2S, free MeSH, and/or salt-treated MeSH but were unrelated to salt-treated H2S. The free sulfhydryl concentrations and their associated aromas appeared to be suppressed by specific Cu fractions in the wines. This study provides evidence of the relevant measures of reductive aroma compounds and their relation to off-odors and Cu fractions.


Assuntos
Cobre , Odorantes , Compostos de Sulfidrila , Vinho , Vinho/análise , Odorantes/análise , Compostos de Sulfidrila/análise , Humanos , Cobre/análise , Cromatografia Gasosa/métodos , Paladar , Sulfeto de Hidrogênio/análise , Feminino , Masculino , Adulto , Oxirredução , Pessoa de Meia-Idade , Olfato , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
5.
An Acad Bras Cienc ; 96(2): e20230373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747835

RESUMO

Bioactive substances can be found in wine lees, a waste from the winemaking industry. This work developed two formulations, a nanoemulsion with coconut oil (NE-OC) and a nanoemulsion with coconut oil and 0.5% of wine lees extract (NE-OC-Ext), to investigate their effect on untreated, bleached, and bleached-colored hair. The oil-in-water (O/W) nanoemulsions were prepared with coconut oil, TweenTM 80, SpanTM 80, AristoflexTM AVC, Conserve NovaMit MFTM, wine lees extract, and deionized water. The hydration measurements were carried out using a Corneometer® CM 825 with the capacitance method. Scanning electron microscopy (SEM) was used to characterize the effect of formulations on hair fibers. Differential Thermal Analysis (DTA) was to assess the thermal stability and compatibility of wine lees and coconut oil in formulations. Compared to NE-OC, NE-OC-Ext showed a greater hydration effect on bleached-colored hair. DTA showed that NE-OC-Ext presented a smaller number of exothermic degradation events than those of NE-OC, suggesting good interaction and compatibility of the wine lees extract in this formulation. This study highlights the value of wine lees, a residue from the winemaking process, and its possibility of use as raw material for the cosmetic hair industry since it shows a greater moisturizing potential in colored hair.


Assuntos
Óleo de Coco , Emulsões , Vinho , Vinho/análise , Óleo de Coco/química , Microscopia Eletrônica de Varredura , Cabelo/química , Cabelo/efeitos dos fármacos , Humanos , Química Verde/métodos
6.
Food Res Int ; 186: 114319, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729690

RESUMO

The "outstanding and unique aged aroma" of Chinese Chenxiang-type baijiu (CXB)-Daoguang 25 (DG25) mainly originates from a "extraordinary storage technology" of Mujiuhai (a wooden container), so it is mysterious and interesting. In this study, an untargeted GC/MS-based metabolomics was used to reveals the volatile differential metabolites for discriminating six different vintages of DG25 combing with chemometrics. A total of 100 volatile metabolites (including unknowns) were extracted and identified, including esters (41%), alcohols (10%) and acids (7%) so on. Finally, 33 differential metabolites were identified as aging-markers. Among them, 25 aging-markers showed a downtrend, including 17 esters such as ethyl acetate, ethyl hexanoate and ethyl palmitate so on. Moreover, it was interesting and to further study that furans showed a significant downtrend. Statistically speaking, ethyl benzoate played an important role in discriminating vintage of 1Y and 3Y, and the other 24 differential metabolites with downtrend discriminating the unstored (0Y-aged) DG25. Eight differential metabolites, such as ethyl octanoate, benzaldehyde, 3-methylbutanol and 1,1-diethoxyaccetal so on increased during aging of DG25, and they played a statistical role in discriminating the 5Y-, 10Y- and 20Y-aged DG25. This study provides a theoretical basis way for the formation mechanism of aging aroma for CXB.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Odorantes , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metabolômica/métodos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Odorantes/análise , Vinho/análise , Bebidas Alcoólicas/análise
7.
Food Res Int ; 186: 114332, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729715

RESUMO

The protein instability with haze formation represents one of the main faults occurring in white and rosé wines. Among the various solutions industrially proposed, aspergillopepsin I (AP-I) supplementation coupled with must heating (60-75 °C) has been recently approved by OIV and the European Commission for ensuring protein stability of wines. This study investigates the impact of AP-I either applied independently or in combination with flash pasteurization on the chemical composition of grape must and wines derived from Sauvignon Blanc and Gewürztraminer. The efficacy on protein stability of a complete treatment combining heat (70 °C) and AP-I (HP) was confirmed through heat test and bentonite requirement, although no differences were observed between must heating and HP treatments. However, high-performance liquid chromatography analysis of unstable pathogenesis-related proteins revealed that AP-I supplementation reduced chitinases and thaumatin-like proteins compared to the non-enzymed samples, with and without must heating. Amino acid increase was reported only in HP musts, particularly in Sauvignon Blanc. The concentration of yeast-derived aroma compounds in Gewürztraminer wines was increased by must heating; compared to controls, flash pasteurization rose the overall acetate esters content of 85 % and HP of 43 %, mostly due to isoamyl acetate. However, heat treatments -with or without AP-I- reduced terpenes up to 68 %. Despite the different aroma profiles, no differences were observed for any descriptor for both varieties in wine tasting, and only a slight decrease trend was observed for the floral intensity and the typicality descriptors in heated wines.


Assuntos
Temperatura Alta , Odorantes , Pasteurização , Vitis , Vinho , Vinho/análise , Pasteurização/métodos , Vitis/química , Odorantes/análise , Manipulação de Alimentos/métodos , Estabilidade Proteica
8.
Food Res Int ; 186: 114337, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729718

RESUMO

A major concern for wineries is haze formation in white wines due to protein instability. Despite its prevalent use, the conventional bentonite method has shortcomings, including potential alteration of color and aroma, slow processing times, and notable wine wastage. Zirconium oxide (ZrO2) effectively removes proteins without affecting wine characteristics. However, producing cost-effective ZrO2 materials with efficient protein removal capabilities poses a significant challenge. This research aims to assess the viability of designing a porous material impregnated with zirconia to remove turbidity-causing proteins effectively. For this purpose, the support material alone (Al2O3) and the zirconia-impregnated support (ZrO2/Al2O3) were subjected to different calcination temperatures. It was observed that high-temperature treatments (750 °C) enhanced wine stability and protein adsorption capacity. The optimal adsorbent achieved a notable reduction in turbidity, decreasing the ΔNTU from 42 to 18, alongside a significant 44 % reduction in the total protein content, particularly affecting proteins in the molecular weight range of 10 to 70 kDa. This result is attributed to modifying the textural properties of ZrO2/Al2O3, characterized by the reduction of acidic sites, augmented pore diameters from 4.81 to 7.74 nm, and the emergence of zirconia clusters across the surface of the porous support. In summary, this study presents the first application of zirconia on the alumina support surface for protein stabilization in white wine. Combining ZrO2/Al2O3 and a high-temperature treatment emerges as a promising, cost-efficient, and environmentally sustainable strategy for protein removal in white wine.


Assuntos
Óxido de Alumínio , Vinho , Zircônio , Vinho/análise , Zircônio/química , Óxido de Alumínio/química , Adsorção , Estabilidade Proteica , Temperatura Alta , Manipulação de Alimentos/métodos
9.
Sensors (Basel) ; 24(9)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38733058

RESUMO

Based on the current research on the wine grape variety recognition task, it has been found that traditional deep learning models relying only on a single feature (e.g., fruit or leaf) for classification can face great challenges, especially when there is a high degree of similarity between varieties. In order to effectively distinguish these similar varieties, this study proposes a multisource information fusion method, which is centered on the SynthDiscrim algorithm, aiming to achieve a more comprehensive and accurate wine grape variety recognition. First, this study optimizes and improves the YOLOV7 model and proposes a novel target detection and recognition model called WineYOLO-RAFusion, which significantly improves the fruit localization precision and recognition compared with YOLOV5, YOLOX, and YOLOV7, which are traditional deep learning models. Secondly, building upon the WineYOLO-RAFusion model, this study incorporated the method of multisource information fusion into the model, ultimately forming the MultiFuseYOLO model. Experiments demonstrated that MultiFuseYOLO significantly outperformed other commonly used models in terms of precision, recall, and F1 score, reaching 0.854, 0.815, and 0.833, respectively. Moreover, the method improved the precision of the hard to distinguish Chardonnay and Sauvignon Blanc varieties, which increased the precision from 0.512 to 0.813 for Chardonnay and from 0.533 to 0.775 for Sauvignon Blanc. In conclusion, the MultiFuseYOLO model offers a reliable and comprehensive solution to the task of wine grape variety identification, especially in terms of distinguishing visually similar varieties and realizing high-precision identifications.


Assuntos
Algoritmos , Vitis , Vinho , Vitis/classificação , Vinho/análise , Vinho/classificação , Aprendizado Profundo , Frutas/química
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124357, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38692110

RESUMO

This study described the preparation of an azide covalent organic framework-embedded molecularly imprinted polymers (COFs(azide)@MIPs) platform for urea adsorption and indirect ethyl carbamate (EC) removal from Chinese yellow rice wine (Huangjiu). By modifying the pore surface of COFs using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, COFs(azide) with a high fluorescence quantum yield and particular recognition ability were inventively produced. In order to selectively trap urea, the COFs(azide) were encased in an imprinted shell layer via imprinting technology. With a detection limit (LOD) of 0.016 µg L-1 (R2 = 0.9874), the COFs(azides)@MIPs demonstrated a good linear relationship with urea in the linear range of 0-5 µg L-1. Using real Huangjiu samples, the spiking recovery trials showed the viability of this sensing platform with recoveries ranging from 88.44 % to 109.26 % and an RSD of less than 3.40 %. The Huangjiu processing model system achieved 38.93 % EC reduction by COFs(azides)@MIPs. This research will open up new avenues for the treatment of health problems associated with fermented alcoholic beverages, particularly Huangjiu, while also capturing and removing hazards coming from food.


Assuntos
Polímeros Molecularmente Impressos , Ureia , Uretana , Vinho , Uretana/análise , Uretana/química , Polímeros Molecularmente Impressos/química , Ureia/análise , Ureia/química , Vinho/análise , Espectrometria de Fluorescência/métodos , Azidas/química , Limite de Detecção , Adsorção , Estruturas Metalorgânicas/química , Impressão Molecular/métodos
11.
J Agric Food Chem ; 72(20): 11606-11616, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38722802

RESUMO

In this work, three MP extracts obtained from Torulaspora delbrueckii were added to red wine, and the changes in phenolic composition, color, and astringency were evaluated by HPLC-DAD-ESI-MS, tristimulus colorimetry, and sensory analysis, respectively. The MP extracts modified wine phenolic composition differently depending on the type of MP. Moreover, two MP extracts were able to reduce wine astringency. The fact that the MP-treated wines showed an increased flavanol content suggests the formation of MP-flavanol aggregates that remain in solution. Furthermore, the formation of these aggregates may hinder the interaction of flavanols with salivary proteins in the mouth. The effect of these MPs might be associated with their larger size, which could influence their ability to bind flavanols and salivary proteins. However, one of the astringent-modulating MPs also produced a loss of color, highlighting the importance of assessing the overall impact of MPs on the organoleptic properties of wine.


Assuntos
Paladar , Torulaspora , Vinho , Vinho/análise , Humanos , Torulaspora/metabolismo , Torulaspora/química , Fenóis/metabolismo , Fenóis/química , Cor , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Cromatografia Líquida de Alta Pressão , Feminino , Masculino , Glicoproteínas de Membrana
12.
J Agric Food Chem ; 72(20): 11617-11628, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38728580

RESUMO

When grapes are exposed to wildfire smoke, certain smoke-related volatile phenols (VPs) can be absorbed into the fruit, where they can be then converted into volatile-phenol (VP) glycosides through glycosylation. These volatile-phenol glycosides can be particularly problematic from a winemaking standpoint as they can be hydrolyzed, releasing volatile phenols, which can contribute to smoke-related off-flavors. Current methods for quantitating these volatile-phenol glycosides present several challenges, including the requirement of expensive capital equipment, limited accuracy due to the molecular complexity of the glycosides, and the utilization of harsh reagents. To address these challenges, we proposed an enzymatic hydrolysis method enabled by a tailored enzyme cocktail of novel glycosidases discovered through genome mining, and the generated VPs from VP glycosides can be quantitated by gas chromatography-mass spectrometry (GC-MS). The enzyme cocktails displayed high activities and a broad substrate scope when using commercially available VP glycosides as the substrates for testing. When evaluated in an industrially relevant matrix of Cabernet Sauvignon wine and grapes, this enzymatic cocktail consistently achieved a comparable efficacy of acid hydrolysis. The proposed method offers a simple, safe, and affordable option for smoke taint analysis.


Assuntos
Frutas , Cromatografia Gasosa-Espectrometria de Massas , Glicosídeo Hidrolases , Glicosídeos , Fenóis , Fumaça , Vitis , Hidrólise , Glicosídeos/química , Glicosídeos/metabolismo , Glicosídeos/análise , Fumaça/análise , Glicosídeo Hidrolases/metabolismo , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Fenóis/química , Fenóis/metabolismo , Vitis/química , Frutas/química , Frutas/enzimologia , Vinho/análise , Incêndios Florestais , Biocatálise
13.
Funct Plant Biol ; 512024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38743838

RESUMO

Soil salinisation is an important abiotic stress faced in grape cultivating, leading to weakened plant vigour and reduced fruit quality. Melatonin as a novel hormone has shown positive exogenous application value. Therefore, this study used wine grape (Vitis vinifera ) 'Pinot Noir' as a test material to investigate the changes of foliar spraying with different concentrations of melatonin on the physiology and fruit quality of wine grapes in a field under simulated salt stress (200mmolL-1 NaCl). The results showed that foliar spraying of melatonin significantly increased the intercellular CO2 concentration, maximum photochemical quantum yield of PSII, relative chlorophyll and ascorbic acid content of the leaves, as well as the single spike weight, 100-grain weight, transverse and longitudinal diameters, malic acid, α-amino nitrogen and ammonia content of fruits, and decreased the initial fluorescence value of leaves, ascorbate peroxidase activity, glutathione content, fruit transverse to longitudinal ratio and tartaric acid content of plants under salt stress. Results of the comprehensive evaluation of the affiliation function indicated that 100µmolL-1 melatonin treatment had the best effect on reducing salt stress in grapes. In summary, melatonin application could enhance the salt tolerance of grapes by improving the photosynthetic capacity of grape plants under salt stress and promoting fruit development and quality formation, and these results provide new insights into the involvement of melatonin in the improvement of salt tolerance in crop, as well as some theoretical basis for the development and industrialisation of stress-resistant cultivation techniques for wine grapes.


Assuntos
Frutas , Melatonina , Fotossíntese , Folhas de Planta , Estresse Salino , Vitis , Vitis/efeitos dos fármacos , Vitis/fisiologia , Vitis/crescimento & desenvolvimento , Melatonina/farmacologia , Melatonina/administração & dosagem , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Estresse Salino/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Clorofila/metabolismo , Ácido Ascórbico/farmacologia , Vinho
14.
Sci Rep ; 14(1): 10124, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698114

RESUMO

Despite the high energetic cost of the reduction of sulfate to H2S, required for the synthesis of sulfur-containing amino acids, some wine Saccharomyces cerevisiae strains have been reported to produce excessive amounts of H2S during alcoholic fermentation, which is detrimental to wine quality. Surprisingly, in the presence of sulfite, used as a preservative, wine strains produce more H2S than wild (oak) or wine velum (flor) isolates during fermentation. Since copper resistance caused by the amplification of the sulfur rich protein Cup1p is a specific adaptation trait of wine strains, we analyzed the link between copper resistance mechanism, sulfur metabolism and H2S production. We show that a higher content of copper in the must increases the production of H2S, and that SO2 increases the resistance to copper. Using a set of 51 strains we observed a positive and then negative relation between the number of copies of CUP1 and H2S production during fermentation. This complex pattern could be mimicked using a multicopy plasmid carrying CUP1, confirming the relation between copper resistance and H2S production. The massive use of copper for vine sanitary management has led to the selection of resistant strains at the cost of a metabolic tradeoff: the overproduction of H2S, resulting in a decrease in wine quality.


Assuntos
Cobre , Fermentação , Sulfeto de Hidrogênio , Metalotioneína , Odorantes , Saccharomyces cerevisiae , Vitis , Vinho , Vinho/análise , Cobre/metabolismo , Vitis/microbiologia , Saccharomyces cerevisiae/metabolismo , Sulfeto de Hidrogênio/metabolismo , Odorantes/análise , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Sulfitos/farmacologia , Controle de Pragas/métodos
15.
Food Res Int ; 183: 114195, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760130

RESUMO

Anthocyanins are polyphenolic compounds that provide pigmentation in plants as reflected by pH-dependent structural transformations between the red flavylium cation, purple quinonoidal base, blue quinonoidal anion, colourless hemiketal, and pale yellow chalcone species. Thermodynamically stable conditions of hydrated plant cell vacuoles in vivo correspond to the colourless hemiketal, yet anthocyanin colour expression appears in an important variety of hues within plant organs such as flowers and fruit. Moreover, anthocyanin colour from grape berries is significant in red winemaking processes as it plays a crucial role in determining red wine quality. Here, nonlinear ordinary differential equations were developed to represent the evolution in concentration of various anthocyanin species in both monomeric (chemically reactive) and self-associated (temporally stable) forms for the first time, and simulations were verified experimentally. Results indicated that under hydrating conditions, anthocyanin pigmentation is preserved by self-association interactions, based on pigmented monomeric anthocyanins experiencing colour loss whereas colour-stable self-associated anthocyanins increase in concentration nonlinearly over time. In particular, self-association of the flavylium cation and the quinonoidal base was shown to influence colour expression and stability within Geranium sylvaticum flower petals and Vitis vinifera grape skins. This study ultimately characterises fundamental mechanisms of anthocyanin stabilisation and generates a quantitative framework for anthocyanin-containing systems.


Assuntos
Antocianinas , Cor , Vitis , Antocianinas/metabolismo , Vitis/química , Cinética , Vinho/análise , Frutas/química , Concentração de Íons de Hidrogênio , Dinâmica não Linear
16.
Food Res Int ; 187: 114391, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763653

RESUMO

This study investigates the intricate relationship between sociodemographic factors, social dominance orientation (SDO), and perceptions of wine in France. Emphasizing the symbolic role of wine in French culture, and employing a survey-based approach, the research explores how societal hierarchies and individual positioning within these structures influence the appraisal of rosé wine. The findings revealed that sociodemographic factors, particularly education level, significantly influence wine appraisal, while social dominance orientation serves as a mediating factor. This research contributes to the understanding of the cultural and social dynamics shaping wine consumption in France, highlighting the fact that wine appraisal is deeply embedded in societal structures.


Assuntos
Predomínio Social , Vinho , Humanos , França , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Fatores Sociodemográficos , Inquéritos e Questionários , Idoso , Adolescente , Cultura , Fatores Socioeconômicos
17.
Food Res Int ; 187: 114414, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763663

RESUMO

Red wine colloids, crucial in determining wine quality and stability, are understudied due to inadequate techniques for studying them effectively in the natural wine environment. Recently, Asymmetrical Flow Field-flow Fractionation (AF4) with online multidetection has emerged as a novel analytical tool for quantifying, fractionating, and characterizing red wine colloids in their native state. This study aimed to characterize the colloidal composition of 24 monovarietal Italian wines produced without filtration, oak contact, fining treatments, malolactic fermentation, macerating enzymes or ageing on yeast lees. AF4 analysis allowed quantification and characterization of wine colloids based on light scattering signal (MALS; gyration radius - Rg), size (hydrodynamic radius - Rh) and absorbance (A280 & A520 nm). The results showed that each wine contained up to five distinct colloids' populations, varying in size and gyration radii. Despite possessing very similar Rh, most colloids exhibited great differences in compactness, as indicated by their varying Rg values. Comparing the A280 signal of whole wines to those of wines containing only species larger than 5 kDa (considered colloids) allowed to calculate the percentage of molecules involved in colloidal particles assembly, ranging from 1 to 44 % of the total A280 absorbing compounds, reflecting the diversity among wines. The A520 signal indicated the presence of polymeric pigments in the colloidal fraction. Notably, colored colloids all had Rg > 20 nm, indicating their association with other colloidal-forming compounds. This observation led to the conclusion that, apart from free anthocyanins and polymeric pigments, the color of red wines is also due to colloidal particles formed by the latter bound to proteins, with their quantity being highly variable across wines of different origin. These findings, which highlight the fundamental role of proteins in shaping the colloidal status of red wines, were utilized to propose an updated hypothetical model for colloidal aggregation in red wine.


Assuntos
Coloides , Fracionamento por Campo e Fluxo , Vinho , Vinho/análise , Coloides/química , Fracionamento por Campo e Fluxo/métodos , Fermentação , Tamanho da Partícula
18.
Food Res Int ; 187: 114411, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763664

RESUMO

Price is one of the most important product-extrinsic factors influencing the consumers' response to, and presumably experience of, wine. This is ironic inasmuch as the research tends to highlight either no, or else even a slightly negative relationship between price and liking in typical consumers when they taste wines blind. Nevertheless, providing price information, especially when it is high leads to enhanced taste ratings, especially for low to mid-priced wines. Similarly, bottle and label information (that makes a wine look cheaper or more expensive) has also been shown to influence the evaluation of wine by regular consumers (i.e., non-experts). Indeed, product-extrinsic information often appears to outweigh the product-intrinsic sensory attributes of wine in people's hedonic (in not necessarily in their sensory-discriminative) ratings. Such findings therefore highlight the importance of cognitive as compared to direct sensory cues in the evaluation of wine. This narrative historical review critically reviews and evaluates the published experimental literature that has examined the impact of price on wine ratings.


Assuntos
Cognição , Comportamento do Consumidor , Paladar , Vinho , Humanos , Comércio , Percepção Gustatória
19.
J Appl Microbiol ; 135(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38621715

RESUMO

AIMS: To compare the species diversity and composition of indigenous yeast communities of hybrid grapes from conventionally and organically cultivated vineyards of an emerging cool-climate wine producing region. METHODS AND RESULTS: Illumina MiSeq sequences from L'Acadie blanc grape musts were processed and filtered to characterize indigenous yeast communities in organic and conventional vineyards of the Annapolis Valley wine region in Nova Scotia, Canada. While cultivation practice was not associated with yeast diversity or species richness, there was a strong effect on yeast community composition, with conventional vineyards characterized by higher proportions of Sporidiobolales and Filobasidium magnum, and organic vineyards supporting Filobasidium species other than F. magnum and higher proportions of Symmetrospora. There was also variation in yeast community composition among individual vineyards, and from year to year. CONCLUSIONS: This is the first comprehensive assessment of yeasts associated with hybrid grapes grown using different cultivation practices in a North American cool climate wine region. Communities were dominated by basidiomycete yeasts and species composition of these yeasts differed significantly between vineyards employing organic and conventional cultivation practices. The role of basidiomycete yeasts in winemaking is not well understood, but some species may influence wine characteristics.


Assuntos
Vitis , Vinho , Leveduras , Vitis/microbiologia , Vinho/microbiologia , Vinho/análise , Leveduras/genética , Leveduras/classificação , Leveduras/isolamento & purificação , Nova Escócia , Fazendas , Agricultura Orgânica
20.
Anal Methods ; 16(18): 2948-2958, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38669009

RESUMO

Herein, a novel type of phosphorus and iron-doped carbon dot (P,Fe-CD) with outstanding peroxidase activity and excellent fluorescence performance was hydrothermally synthesized to colorimetrically and fluorimetrically detect tannic acid (TA). In the presence of 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2, the P,Fe-CDs could oxidize colorless TMB to a blue oxidation product (oxTMB) resulting in an increased value of absorbance. Simultaneously, the fluorescence intensity of P,Fe-CDs at 430 nm could be quenched owing to the fluorescence resonance energy transfer (FRET) between P,Fe-CDs and the generated oxTMB. Meanwhile, after adding the TA to the system containing TMB, H2O2 and P,Fe-CDs, the value of absorbance could be decreased and the fluorescence could be recovered because of the reduction reaction between TA and oxTMB. Therefore, fluorescence intensity and value of absorbance could be applied to quantitatively detect TA with good linearities between the concentration of TA and the fluorescence intensity/value of absorbance (0.997 and 0.997 for the colorimetric signal and fluorimetric one, respectively) and low limits of detection (0.093 µmol L-1 and 0.053 µmol L-1 for the colorimetry and the fluorimetry, respectively), which was successfully applied to the detection of TA in red wines. Moreover, we applied a smartphone-assisted method to the point-of-care detection of TA with accurate results, providing a new technique for TA detection and food quality monitoring.


Assuntos
Carbono , Pontos Quânticos , Taninos , Vinho , Taninos/química , Vinho/análise , Carbono/química , Pontos Quânticos/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Colorimetria/métodos , Peroxidase/química , Peroxidase/metabolismo , Limite de Detecção , Transferência Ressonante de Energia de Fluorescência/métodos , Benzidinas/química , Oxirredução , Polifenóis
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