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1.
Front Plant Sci ; 14: 1142139, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36938056

RESUMO

Obtaining new grapevine varieties with unique aromas has been a long-standing goal of breeders. Norisoprenoids are of particular interest to wine producers and researchers, as these compounds are responsible for the important varietal aromas in wine, characterized by a complex floral and fruity smell, and are likely present in all grape varieties. However, the single-nucleotide polymorphism (SNP) loci and candidate genes genetically controlling the norisoprenoid content in grape berry remain unknown. To this end, in this study, we investigated 13 norisoprenoid traits across two years in an F1 population consisting of 149 individuals from a hybrid of Vitis vinifera L. cv. Muscat Alexandria and V. vinifera L. cv. Christmas Rose. Based on 568,953 SNP markers, genome-wide association analysis revealed that 27 candidate SNP loci belonging to 18 genes were significantly associated with the concentrations of norisoprenoid components in grape berry. Among them, 13 SNPs were confirmed in a grapevine germplasm population comprising 97 varieties, including two non-synonymous mutations SNPs within the VvDXS1 and VvGGPPS genes, respectively in the isoprenoid metabolic pathway. Genotype analysis showed that the grapevine individuals with the heterozygous genotype C/T at chr5:2987350 of VvGGPPS accumulated higher average levels of 6-methyl-5-hepten-2-one and ß-cyclocitral than those with the homozygous genotype C/C. Furthermore, VvGGPPS was highly expressed in individuals with high norisoprenoids concentrations. Transient overexpression of VvGGPPS in the leaves of Vitis quinquangularis and tobacco resulted in an increase in norisoprenoid concentrations. These findings indicate the importance of VvGGPPS in the genetic control of norisoprenoids in grape berries, serving as a potential molecular breeding target for aroma.

2.
Foods ; 12(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36900598

RESUMO

As one of the most promising wine regions in China, the eastern foothills of the Helan Mountain (EFHM) in the Ningxia Hui Autonomous Region has attracted great attention recently. Geographically, EFHM is divided into six sub-regions, namely Shizuishan, Xixia, Helan, Qingtongxia, Yongning and Hongsipu. However, there have been few reports on the character and differences between wines in the six sub-regions. In this experiment, a total of 71 commercial Cabernet Sauvignon wines from six sub-regions were collected, and their phenolic compounds, visual properties and mouthfeel were investigated. The results showed that wines from the six sub-regions of EFHM showed distinctive phenolic profiles and could be distinguished through the OPLS-DA mode using 32 potential markers. In terms of color, Shizuishan wines showed higher a* values and lower b* values. The sensory evaluation showed that Hongsipu wines had higher astringency strength and lower tannin texture. The overall results implied that the phenolic compounds of wines in different sub-regions were affected by terroir conditions. To the best of our knowledge, this is the first time that a wide coverage of phenolic compounds has been analysed for wines from the sub-regions of EFHM, which could provide valuable information in deciphering the terroir of EFHM.

3.
Food Res Int ; 149: 110660, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600662

RESUMO

A cross-modal interaction may exist between the perception of saltiness and the pungency elicited by Sichuan pepper oleoresin (Spo). Thirty-one hypersensitive panelists were selected to participate in this study. Spo solutions dissolved in different NaCl concentrations, ranging from 1.25 g/L to 167.9 g/L, were used as the test samples. The rated difference from control, the generalized labeled magnitude scale (gLMS), and the time-intensity (TI) method were used to determine the detection threshold (DT), the recognition threshold (RT), the intensity, and the dynamic perception of pungent sensation. The results revealed that the pungency thresholds increased significantly (p < 0.01) in the solution with a high NaCl (167.9 g/L) concentration. Furthermore, high NaCl solutions suppressed the pungency intensity at all Spo concentrations except for 0.02 g Spo/L in water (p < 0.05). The TI and principal component analysis (PCA) results showed that an increase in the Spo concentration prolonged the duration of the pungency sensation. However, the maximum intensity, the time to reach maximum intensity, the decay time of perception, and the end time of perception of the Spo solutions ranging from 2.13 g/L to 4.69 g/L were significantly reduced at medium (42.95 g/L) and high NaCl concentrations. Since the salty and pungency sensations exhibited by NaCl and Spo are common flavor combinations in food products and dishes, studying the influence of saltiness on the dynamic perception of pungent sensation not only aids the development of oral cleaners during pungency evaluation but also presents significant theoretical and practical value in creating pungent food and cuisine based on consumer preferences.


Assuntos
Sensação , Cloreto de Sódio , Percepção , Extratos Vegetais , Verduras
4.
Food Sci Biotechnol ; 29(12): 1641-1653, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33282431

RESUMO

Berries of six Vitis davidii Foex (spine grape) cultivars ('Baiputao', 'Gaoshan 1', 'Gaoshan 2', 'Seputao', 'Miputao', and 'Tianputao') were harvested from a commercial vineyard in Hunan Province in China. Free and bound volatile compounds and fatty acids were analyzed by GC-MS, and amino acids were analyzed by HPLC. 'Tianputao' and 'Miputao' were characterized by relatively higher concentrations of aromatic amino acids and lower concentrations of branched-chain amino acids. The major free volatile compounds of spine grapes were hexanal, (E)-2-hexenal, 1-hexanol, (E)-2-hexenol, (E)-ß-damascenone, and benzeneacetaldehyde. The major glycosidically bound volatile compounds identified were 1-hexanol, menthol, nerol, 1-butanol, 3-methyl-3-butenol, benzenemethanol, ß-phenylethanol, eugenol, and guaiacol. (E)-ß-damascenone, benzeneacetaldehyde, guaiacol, and eugenol had odor activity values (OAVs) > 1 in all cultivar grapes. Partial least squares discriminant analysis (PLS-DA) revealed 'Tianputao' to be distinct from the other cultivars due to its relatively higher concentrations of major terpenoids, norisoprenoids, higher alcohols, and aromatic amino acids.

5.
Food Chem ; 287: 186-196, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30857688

RESUMO

Freezing-thawing events contribute to the unique aroma profile of icewines. Differences in key odor-active volatile compounds between 'Beibinghong' (Vitis amurensis × V. vinifera) icewines and dry wines were investigated by gas chromatography-olfactometry and gas chromatography-mass spectrometry. Acceptable agreement between the olfactometric and quantitative results was obtained. 'Beibinghong' icewine was characterized by high concentrations of volatile phenols, lactones, (E)-ß-damascenone, and phenylacetaldehyde, which were associated with on-vine freezing-thawing events in grape. Low concentrations of higher alcohol acetates and ethyl esters of fatty acids were attributed to hyperosmotic stress during fermentation. The overall aroma of icewine could be mimicked by reconstitution containing 44 identified volatiles. Partial least squares regression analysis demonstrated that the concentrations of these volatile compounds determined the distinct sensory profiles of icewines, which have higher intensities of honey/sweet, smoky, caramel, dried fruit, apricot/peach, and floral aromas, and lower intensities of fresh fruity and herbaceous notes in comparison with dry wines.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Olfatometria , Vinho/análise , Ésteres , Fermentação , Manipulação de Alimentos/métodos , Congelamento , Frutas/química , Humanos , Análise dos Mínimos Quadrados , Norisoprenoides , Paladar , Vitis/química , Compostos Orgânicos Voláteis/análise
6.
J Food Sci ; 83(1): 30-38, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29210459

RESUMO

To develop a robust tool for Chinese commercial wines' varietal, regional, and vintage authentication, phenolic compounds in 121 Chinese commercial dry red wines were detected and quantified by using high-performance liquid chromatography triple-quadrupole mass spectrometry (HPLC-QqQ-MS/MS), and differentiation abilities of principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA) were compared. Better than PCA and PLS-DA, OPLS-DA models used to differentiate wines according to their varieties (Cabernet Sauvignon or other varieties), regions (east or west Cabernet Sauvignon wines), and vintages (young or old Cabernet Sauvignon wines) were ideally established. The S-plot provided in OPLS-DA models showed the key phenolic compounds which were both statistically and biochemically significant in sample differentiation. Besides, the potential of the OPLS-DA models in deeper sample differentiating of more detailed regional and vintage information of wines was proved optimistic. On the basis of our results, a promising theoretic design for wine authentication was further proposed for the first time, which might be helpful in practical authentication of more commercial wines. PRACTICAL APPLICATION: The phenolic data of 121 Chinese commercial dry red wines was processed with different statistical tools for varietal, regional, and vintage differentiation. A promising theoretical design was summarized, which might be helpful for wine authentication in practical situation.


Assuntos
Fenóis/análise , Vinho/análise , Bebidas Alcoólicas/análise , China , Cromatografia Líquida de Alta Pressão/métodos , Análise Discriminante , Análise dos Mínimos Quadrados , Espectrometria de Massas/métodos , Análise de Componente Principal , Espectrometria de Massas em Tandem , Vinho/classificação
7.
J Sci Food Agric ; 98(1): 104-112, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28543285

RESUMO

BACKGROUND: Monosaccharides, organic acids and amino acids are the important flavour-related components in wines. The aim of this article is to develop and validate a method that could simultaneously analyse these compounds in wine based on silylation derivatisation and gas chromatography-mass spectrometry (GC-MS), and apply this method to the investigation of the changes of these compounds and speculate upon their related influences on Cabernet Sauvignon wine flavour during wine ageing. This work presented a new approach for wine analysis and provided more information concerning red wine ageing. RESULTS: This method could simultaneously quantitatively analyse 2 monosaccharides, 8 organic acids and 13 amino acids in wine. A validation experiment showed good linearity, sensitivity, reproducibility and recovery. Multiple derivatives of five amino acids have been found but their effects on quantitative analysis were negligible, except for methionine. The evolution pattern of each category was different, and we speculated that the corresponding mechanisms involving microorganism activities, physical interactions and chemical reactions had a great correlation with red wine flavours during ageing. CONCLUSION: Simultaneously quantitative analysis of monosaccharides, organic acids and amino acids in wine was feasible and reliable and this method has extensive application prospects. © 2017 Society of Chemical Industry.


Assuntos
Ácidos/química , Aminoácidos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monossacarídeos/química , Vinho/análise , Humanos , Odorantes/análise , Olfato , Fatores de Tempo
8.
Int J Mol Sci ; 18(12)2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29261101

RESUMO

C6 volatiles are synthesized through lipoxygenase-hydroperoxide lyase (LOX-HPL) pathway and these volatiles play important roles in the aromatic quality of grape berries. This study investigated the evolution of both C6 volatiles and the key genes in the LOX-HPL pathway in different table grape cultivars during the berry development period, and further assessed the correlation between the accumulation of C6 volatiles and the expression of these genes in these cultivars. Results showed that hexanal, (E)-2-hexenal, (E)-2-hexen-1-ol and (Z)-3-hexen-1-ol were found to be the dominant C6 volatiles in these ripened grape cultivars under two consecutive vintages, and their flavor notes were incorporated in the overall aroma of these cultivars. The cultivar "Xiangfei" showed the most abundant level of C6 aldehydes and C6 acid, whereas the cultivar "Tamina" and "Moldova" possessed the highest C6 alcohol content. The "Muscat of Alexandria" cultivar was found to contain the highest level of C6 esters. C6 volatiles were grouped into three evolutionary patterns in these cultivars during berry development, and their evolution was consistent with the evolution of the LOX-HPL pathway genes' expression. Pearson's correlation analysis indicated that the LOX-HPL-pathway-related genes were correlated to the accumulation of C6 volatiles in these cultivars, and VvLOXA appeared to be an important gene that regulated the synthesis of all C6 volatiles.


Assuntos
Aldeído Liases/genética , Sistema Enzimático do Citocromo P-450/genética , Lipoxigenase/genética , Óleos Voláteis/metabolismo , Proteínas de Plantas/genética , Vitis/genética , Aldeído Liases/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Regulação da Expressão Gênica de Plantas , Lipoxigenase/metabolismo , Proteínas de Plantas/metabolismo , Vitis/enzimologia , Vitis/metabolismo
9.
Food Chem ; 228: 125-135, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28317704

RESUMO

The conditions of sample pretreatments and HS-SPME for extracting volatile compounds from raisins were optimized, and the method was validated in the study. Free and glycosidically bound volatile compounds in three different fragrance intensities raisins were analysed using this method. There were 91 compounds identified, and 72, 26 and 8 of these compounds came from fresh grapes, the auto-oxidation of unsaturated fatty acids (UFAO) and the Maillard reaction, respectively. The aroma profiles of Thompson Seedless raisins (TSRs) and Centennial Seedless raisins (CSRs) were similar, while the floral, fruity, green and roasted aromas of CSRs were higher than those of TSRs due to the contributions of benzeneacetaldehyde, 2-pentylfuran, (E)-2-nonenal and 3-ethyl-2,5-dimethyl pyrazine. Decanal, rose oxide, geraniol, linalool and ß-damascenone made the floral and fruity aromas of Zixiang Seedless raisins (ZSRs) greater than those in TSRs and CSRs, but the green and roasted aroma intensities of ZSRs were lower.


Assuntos
Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Vitis/química , Glicosídeos , Odorantes , Compostos Orgânicos Voláteis/análise
10.
Molecules ; 22(1)2016 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-28036078

RESUMO

A nitrogen deficiency always causes bog bilberry syrup wine to have a poor sensory feature. This study investigated the effect of nitrogen source addition on volatile compounds during bog bilberry syrup wine fermentation. The syrup was supplemented with 60, 90, 120 or 150 mg/L dibasic ammonium phosphate (DAP) before fermentation. Results showed that an increase of DAP amounts accelerated fermentation rate, increased alcohol content, and decreased sugar level. Total phenol and total flavonoid content were also enhanced with the increase of DAP amounts. A total of 91 volatile compounds were detected in the wine and their concentrations were significantly enhanced with the increase of DAP. Ethyl acetate, isoamyl acetate, phenethyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, isobutanol, isoamyl alcohol, levo-2,3-butanediol, 2-phenylethanol, meso-2,3-butanediol, isobutyric acid, hexanoic acid, and octanoic acid exhibited a significant increase of their odor activity value (OAV) with the increase of DAP amounts. Bog bilberry syrup wine possessed fruity, fatty, and caramel flavors as its major aroma, whereas a balsamic note was the least present. The increase of DAP amounts significantly improved the global aroma attributes, thereby indicating that DAP supplementation could promote wine fermentation performance and enhance the sensory quality of bog bilberry syrup wine.


Assuntos
Aromatizantes/análise , Odorantes/análise , Fosfatos/química , Vinho/análise , Aldeídos/análise , Antocianinas/análise , Ésteres/análise , Fermentação , Flavonoides/análise , Cetonas/análise , Fenóis/análise , Vaccinium myrtillus , Compostos Orgânicos Voláteis/análise
11.
Int J Mol Sci ; 17(11)2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27886056

RESUMO

Variety is one of the major factors influencing grape and wine aromatic characteristics. Green leaf volatiles (GLVs), derived from lipoxygenase-hydroperoxides lyase (LOX-HPL) pathway, are important components for the aromatic quality of grapes and wines. However, the varietal difference regarding GLVs accumulation and related gene expression are poorly studied. This work exhibited that the accumulation of various GLVs and the expression of LOX-HPL pathway genes in four Vitis vinifera wine grape cultivars: Syrah, Muscat Tchervine, Gewürztraminer and Chardonnay. The results showed a variety dependence of GLVs profile. Muscat Tchervine harvested grapes contained less C6 aldehydes and the most abundant esters, which corresponded to very low VvLOXA and VvHPL1 expression abundance as well as high VvAAT transcript in this variety. High expression level of both VvLOXA and VvHPL1 paralleled with higher level of C6 aldehydes together with higher alcohols in Syrah grape. Gewürztraminer and Chardonnay grapes had high aldehydes and alcohols as well as low esters, which were resulted from their higher expression level of VvLOXA or VvHPL1 and lower VvAAT. From these above corresponding relations, it is concluded that VvLOXA, VvHPL1 and VvAAT in the LOX-HPL pathway are targets for altering GLVs composition in the grape varieties.


Assuntos
Aldeído Liases/genética , Sistema Enzimático do Citocromo P-450/genética , Frutas/genética , Regulação da Expressão Gênica de Plantas , Lipoxigenase/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Vitis/genética , Álcoois/metabolismo , Aldeído Liases/metabolismo , Aldeídos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Análise Discriminante , Aromatizantes/metabolismo , Frutas/metabolismo , Variação Genética , Lipoxigenase/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Especificidade da Espécie , Vitis/classificação , Vitis/metabolismo , Vinho/análise
12.
Food Chem ; 212: 172-82, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27374521

RESUMO

The evolution of free and glycosidically bound volatile compounds in 'Beibinghong' (Vitis vinifera×Vitis amurensis) grape berries throughout on-vine over-ripening and freezing processes was studied in two vintages. The aroma profiles of 'Beibinghong' icewine berries were characterized by C6 compounds, higher alcohols and terpenoids in free fractions and carbonyl compounds, higher alcohols, C6 alcohols and terpenoids in bound fractions. With regard to free volatile compounds, there was a decrease in the concentration of C6 compounds, terpenols and norisoprenoids and an increase of terpene oxides during over-ripening process. A striking alteration of volatile profile occurred at sub-zero temperatures, particularly for the free fractions such as C6 alcohols, higher alcohols and oxidative terpene derivatives. These changes were attributed to a series of reactions (biotransformation, oxidation and anaerobic metabolism) induced by water loss and especially freeze-thaw cycles. PCA revealed temperature and rainfall affected the accumulation of volatile compounds during over-ripening processes.


Assuntos
Vitis/química , Compostos Orgânicos Voláteis/química , China , Temperatura Baixa
13.
Rapid Commun Mass Spectrom ; 30(13): 1619-26, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27321850

RESUMO

RATIONALE: To develop a reliable and accurate method for the identification of anthocyanins and their subsequent derivatives formed during red grape fermentation and wine maturation. METHODS: By using a Poroshell 120 EC-C18 column in a high-performance liquid chromatography/triple-quadrupole tandem mass spectrometry (HPLC/QqQ-MS/MS) system, combined with multiple reaction monitoring (MRM), it was possible to establish and validate a method for the determination of anthocyanin and a range of complex reaction products. A selected range of six 3-O-glucosidic anthocyanins were used as standards. A database was established from these results. Then various red wines were examined and quantified by this method. RESULTS: With the range of accuracy and precision being 86.97-111.39% and 0.09-4.32%, respectively, the HPLC/QqQ-MS/MS method was found to be a reliable method for anthocyanin detection. By using this HPLC/QqQ-MS/MS method combined with the inclusive database, accurate identification of 95 anthocyanin compounds of different families from various wine samples was systematically achieved in 29 min. CONCLUSIONS: By combining this analytical system with an inclusive database, it was possible to determine a wide range of anthocyanins and related complex derivatives for the first time. We consider that it should be possible to extend this method further to include more complex anthocyanins, and to other complex compounds. Copyright © 2016 John Wiley & Sons, Ltd.

14.
Molecules ; 20(11): 19865-77, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26556321

RESUMO

Phenolic compounds determine the color quality of fruit wines. In this study, the phenolic compound content and composition, color characteristics and changes during 6 months of bottle aging were studied in wines fermented with bog bilberry syrup under three different pHs. The total anthocyanins and total phenols were around 15.12-16.23 mg/L and 475.82 to 486.50 mg GAE/L in fresh wines and declined 22%-31% and about 11% in bottle aged wines, respectively. In fresh wines, eight anthocyanins, six phenolic aids and 14 flavonols, but no flavon-3-ols were identified; Malvidin-3-O-glucoside, petunidin-3-O-glucoside and delphinium-3-O-glucoside were the predominant pigments; Chlorogentic acid was the most abundant phenolic acid, and quercetin-3-O-galactoside and myricetin-3-O-galactoside accounted for nearly 90% of the total flavonols. During 6 months of bottle storage, the amounts of all the monomeric anthocyanins and phenolic acids were reduced dramatically, while the glycosidyl flavonols remained constant or were less reduced and their corresponding aglycones increased a lot. The effects of aging on blueberry wine color were described as the loss of color intensity with a dramatic change in color hue, from initial red-purple up to final red-brick nuances, while the pH of the fermentation matrix was negatively related to the color stability of aged wine.


Assuntos
Polifenóis/química , Vaccinium myrtillus/química , Vinho/análise , Antocianinas/química , Fermentação , Flavonóis/química , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/química , Fenóis/química , Pigmentos Biológicos/análise
15.
Plant Physiol Biochem ; 89: 123-33, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25769137

RESUMO

Volatile compounds are considered important for plants to communicate with each other and interact with their environments. Most wine-producing regions in China feature a continental monsoon climate with hot-wet summers and dry-cold winters, giving grapes markedly different growing environments compared to the Mediterranean or oceanic climates described in previous reports. This study focused on comparing the volatile profiles of Vitis vinifera L. cv. Cabernet Sauvignon berries from two regions with distinct climate characteristics: Changli has a warm and semi-humid summer, and Gaotai has a cool-arid summer and a cold winter. The relationship between meteorological metrics and the concentrations of grape volatiles were also examined. In harvested grapes, benzyl alcohol, phenylethyl alcohol, 1-hexanol and 1-octen-3-ol were more abundant in the Changli berries, while hexanal, heptanal, 2-methoxy-3-isobutylpyrazine, and (E)-ß-damascenone presented higher levels in the Gaotai berries. The fluctuation in the accumulation of volatile compounds observed during berry development was closely correlated with variations in short-term weather (weather in a week), especially rainfall. The concentration of some volatiles, notably aliphatic aldehydes, was significantly related to diurnal temperature differences. The variability during berry development of concentrations for compounds such as C6 volatile compounds, 2-methoxy-3-isobutylpyrazine and (E)-ß-damascenone strongly depended upon weather conditions. This work expands our knowledge about the influence of continental monsoon climates on volatile compounds in developing grape berries. It will also improve the comprehension of the plant response to their surrounding environments through the accumulation of volatiles. The results will help growers to alter viticultural practices according to local conditions to improve the aromatic quality of grapes.


Assuntos
Clima , Frutas/metabolismo , Óleos Voláteis/metabolismo , Vitis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Tempo (Meteorologia) , Vinho , China , Regulação da Expressão Gênica de Plantas , Estações do Ano
16.
Food Chem ; 177: 346-53, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25660896

RESUMO

Volatile compounds in air-dried raisins from Turpan, China were analysed, with 77 volatiles identified in Flame Seedless, Thompson Seedless, and Crimson Seedless raisins, 37 of which had never been reported as raisin volatiles. Odour activity values (OAVs) of these volatiles were calculated; 20 compounds had OAVs above 1. The aroma characters of the three varieties were quite similar except for some differences in the intensity of each aroma character. The main free-form volatiles were ethyl acetate, hexanoic acid, (E,E)-2,4-heptadienal and geraniol, with ß-damascenone, 3-ethyl-2,5-dimethylpyrazine, 1-octen-3-ol and hexanal making the highest contribution to the aroma. Fruity and floral were the main characteristics of the free-form aromas in raisins. The main bound-form volatiles were benzyl alcohol and acetoin, with ß-damascenone contributing most to the bound-form aromas, enhancing the floral, fruity and fatty aroma.


Assuntos
Vitis/química , Compostos Orgânicos Voláteis/química , Benzenossulfonatos , China , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/isolamento & purificação
17.
Int J Mol Sci ; 15(12): 21992-2010, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25470020

RESUMO

Monoterpenoids are a diverse class of natural products and contribute to the important varietal aroma of certain Vitis vinifera grape cultivars. Among the typical monoterpenoids, linalool exists in almost all grape varieties. A gene coding for a nerolidol/linalool (NES/LINS) synthase was evaluated in the role of linalool biosynthesis in grape berries. Enzyme activity assay of this recombinant protein revealed that it could convert geranyl diphosphate and farnesyl diphosphate into linalool and nerolidol in vitro, respectively, and thus it was named VvRILinNer. However, localization experiment showed that this enzyme was only localized to chloroplasts, which indicates that VvRILinNer functions in the linalool production in vivo. The patterns of gene expression and linalool accumulation were analyzed in the berries of three grape cultivars ("Riesling", "Cabernet Sauvignon", "Gewurztraminer") with significantly different levels of monoterpenoids. The VvRILinNer was considered to be mainly responsible for the synthesis of linalool at the early developmental stage. This finding has provided us with new knowledge to uncover the complex monoterpene biosynthesis in grapes.


Assuntos
Frutas/enzimologia , Hidroliases/metabolismo , Monoterpenos/metabolismo , Plastídeos/enzimologia , Sesquiterpenos/metabolismo , Vitis/enzimologia , Vitis/crescimento & desenvolvimento , Monoterpenos Acíclicos , Sequência de Aminoácidos , Eletroforese em Gel de Poliacrilamida , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Fluorescência Verde/metabolismo , Hidroliases/química , Hidroliases/genética , Anotação de Sequência Molecular , Dados de Sequência Molecular , Filogenia , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Frações Subcelulares/enzimologia , Vitis/genética
18.
Plant Physiol Biochem ; 84: 45-56, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25240263

RESUMO

Flavonoids make a very important contribution to the organoleptic qualities of grapes and wines. In this work these were analyzed in Cabernet Sauvignon grown in Changli, Hebei Province in east China and Gaotai, Gansu Province in west China. These regions have distinctly different climates contributing to their different 'terroir'. RNA sequencing was performed to trace transcriptome changes in Cabernet Sauvignon berries at pea size, veraison and ripening, corresponding to E-L 31, 35 and 38. The accumulation of flavonols, flavan-3-ols and anthocyanins together with the expression of relevant genes were analyzed and compared between the two regions. The biosynthesis patterns were similar between two regions, but more flavonols, anthocyanins, and tri-hydroxylated flavonoids accumulated in grapes from Gaotai before berry harvest, possibly due to the higher transcript levels of the genes that encode biosynthetic enzymes and their potential candidate transcription factors. The lower levels of flavan-3-ols, mainly (-)-epigallocatechin, in the pre-veraison grapes from Changli, might be due to limited flow of carbon to the F3'5'H branch pathway, as the ratio of F3'5'H to F3'H was lower in these berries from Changli. It is suggested that the combination of climatic factors profoundly affect the flavonoid pathway in grapes from China, providing regionally specific metabolism patterns.


Assuntos
Flavonoides/metabolismo , Frutas/metabolismo , Proteínas de Plantas/metabolismo , Vitis/metabolismo , Antocianinas/metabolismo , China , Regulação da Expressão Gênica de Plantas
19.
Food Chem ; 163: 6-15, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24912689

RESUMO

A rapid HPLC method has been developed for the simultaneous determination of 23 amino acids, 10 biogenic amines and the ammonium ion in wine. Samples were pre-column derivatised with diethyl ethoxymethylenemalonate and separated using reversed-phase HPLC within 30 min. The matrix effect was evaluated when measuring samples taken from different stages of fermentation. Most compounds showed no obvious matrix effect, whereas proline, ethanolamine and spermine had remarkably different responses to variable concentrations of sugar. High concentrations of sugar affected the pH of the derivatisation reaction system; proline, ethanolamine and spermine derivatives were sensitive to this effect. Matrix-matched calibration was used for the quantification of these compounds. Validation of the method showed that it was accurate, reproducible and efficient for the simultaneous determination of amino acids and biogenic amines in wines during fermentation. As a specific application of the method, red wine samples taken from different stages of fermentation were analysed.


Assuntos
Aminoácidos/análise , Aminas Biogênicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Fermentação , Vinho/análise , Malonatos/química
20.
Food Chem ; 154: 217-29, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24518336

RESUMO

The influence of pre-fermentation cold maceration (CM) on Cabernet Sauvignon wines fermented in two different industrial-scale fermenters was studied. CM treatment had different effects on wine aroma depending on the types of fermenter, being more effective for automatic pumping-over tank (PO-tank) than automatic punching-down tank (PD-tank). When PO-tank was used, CM-treated wine showed a decrease in some fusel alcohols (isobutanol and isopentanol) and an increase in some esters (especially acetate esters). However, no significant changes were detected in these compounds when PD-tank was used. Ethyl 2-hexenoate and diethyl succinate were decreased, while geranylacetone was increased by the CM treatment in both fermenters. ß-Damascenone was increased by the CM treatment in PO-tank fermented wines but decreased in PD-tank fermented wines. The fruity, caramel and floral aroma series were enhanced while chemical series were decreased by the CM treatment in PO-tank fermented wines. The content of (Z)-6-nonen-1-ol in the final wines was positively correlated to CM treatment.


Assuntos
Microbiologia Industrial/métodos , Odorantes/análise , Vitis/química , Compostos Orgânicos Voláteis/análise , Vinho/análise , Reatores Biológicos/microbiologia , Fermentação , Microbiologia Industrial/instrumentação , Vitis/metabolismo , Vitis/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Vinho/microbiologia , Leveduras/metabolismo
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