•ICP-MS could be an useful tool to classify wines according to multi-element contents.•Dilution/digestion sample treatments and internal/external calibrations were assayed.•The minor and trace ...elements did not present differences between these four methods.•However, the best method was digestion with internal calibration for major elements.•Sr, Ca, Mg, Mn, Ba, Ni, Cu, Cs, Pb, Zn, and Na were the wine discriminant elements.
Wines from different grape varieties, geographical zones, soil types, foliar N application, SO2 addition and oak ageing were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). For this purpose, ICP-MS methodology was optimized. The elements which allowed differentiate wines from studied grape varieties were Sr, Ca, Mg and Mn. Geographical zones were classified according to Sr, Ba, Ni, and Cu. Cs and Pb were the main elements to discriminate the wines from the 3 soil types. Wines from several N foliar doses application were classified by Pb, Ni, Mn and Zn. The content of Cs, Mg, Cu and Pb in wines characterized the SO2 addition. Finally, wines storage in barrels were differentiate by Na and Cs concentration. The discriminant functions classify 100% of the wines, with the exception of grape variety (97.0%) and oak ageing (95.8%). Consequently, ICP-MS can be applied to classified wines according to viticultural and oenological factors.
•Foliar application of urea and phenylalanine modified grape phenolic content.•Anthocyanins and flavonols were the phenolic compounds most affected by the foliar treatments.•In general, application ...of urea and phenylalanine improved grape quality.•These practices may help to obtain grapes of higher quality.
Grapevines may require the input of nitrogen to grow and to guarantee an appropriate grape composition. Recently there has been a growing interest in foliar fertilization, which entails a fast and efficient assimilation of the products. The aim of this work was to study the influence of foliar applications of phenylalanine and urea, at two different doses, on grape anthocyanins, flavonols, flavan-3-ols, phenolic acids, and stilbenes. All treatments were applied at veraison and one week later at doses of 0.9 and 1.5kgN/ha. The results showed that the synthesis of phenolic compounds was favoured by foliar applications of phenylalanine and urea. The application of the lowest dose of urea was the most effective treatment, increasing the content of several anthocyanins and flavonols. Moreover, none of the foliar treatments worsened the grape phenolic composition. In conclusion, foliar application of phenylalanine and especially urea, could be an interesting management tool for improving grape quality and their health-promoting properties.
Nitrogen compounds play a key role on grape and wine quality. Their composition in grapes depends mainly on variety, viticultural management, and terroir, and affects fermentation kinetics and the ...volatile compound formation. The aim of this work was to study grape and wine amino acid composition of ungrafted or grafted onto cv. País Carignan grapevines growing under rainfed conditions in ten sites of the Maule Valley (Chile). The results showed that proline was the most abundant amino acid in grapes and wines. In general, Carignan noir grapevines grafted over País showed lower grape amino acid content respect to ungrafted vines. Cool night index (CI) was inversely correlated to several amino acids, showing that their plant synthesis or accumulation increased with lower minimum temperatures during the last month before harvest. Truquilemu (Tru) and Ciénaga de Name (Cdn) sites showed the highest concentration for several amino acids and total amino acid content in grapes, which led to a faster alcoholic fermentation.
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•First study about grape and wine amino acid composition in terms of Valley•Tru and Cdn sites showed high content in grapes which improved fermentation kinetics.•Low night Ts (°C) in the month prior to harvest allowed a high amino acid synthesis.•Grapes from Carignan noir vines grafted with País showed low grape amino acid content.•Carignan noir grapevines behaved as proline accumulator variety.
•β-Carotene and lutein were the most abundant carotenoids in all the grapes.•N and elicitor applications had high impact on grape chlorophyll and carotenoids.•Garnacha were less affect by the ...treatments than were Tempranillo and Graciano varieties.•Tempranillo was the variety most influenced by the foliar treatments.
Photosynthetic pigments, including carotenoids are important secondary metabolites, which play a key role in photosynthesis. There is little information about the effects of nitrogen and elicitor applications on chlorophyll and carotenoid concentrations in grapes. The aim of this work was therefore to study the effects of the foliar application of nitrogen sources and elicitors to Tempranillo, Garnacha and Graciano (Vitis vinifera L.) grapevines on chlorophyll and carotenoid contents. The results showed that β-carotene and lutein were the most abundant carotenoids in all the samples, ranging from 1336 and 227 to 7054 and 1382 μg/g, respectively. The applied treatments had greater impact on chlorophyll and carotenoid contents in Tempranillo grapes than in Graciano and Garnacha varieties. The content of chlorophyll was determined by the variety factor, while the concentration of carotenoids was influenced by the interaction of variety and treatment factors, depending on the type of foliar application.
Light is an energy source and key environmental factor for plants. Out of the different light wavelengths, blue-light is one of the most relevant spectral regions because of its relation to ...anthocyanins biosynthesis. Among the compounds present in grapes, anthocyanins determine their main organoleptic and healthy properties; while a minimum concentration of ammonium and amino acids is necessary for a desirable development of the alcoholic fermentation. Moreover, amino acids are precursors of several volatile compounds synthetized during the fermentation. The aim of this study was to assess the influence of riboflavin (vitamin B2) applications, at harvest and one week later,to grapevine leaves in combination with post-harvest blue-light irradiation on Tempranillo (Vitis vinifera L.) grape anthocyanins and amino acidscomposition. The combination of blue-light irradiation and two riboflavin doses as well as theseindividual factors affected both grape anthocyanins and amino acidsconcentrations. After one week of storage, anthocyanins concentration diminished when clusters were irradiated with blue-light; while for amino acids content, the trend to increase or decrease is dependent on the riboflavin dose applied in vines and the storage time.
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•The 2 doses of riboflavin (0.5 and 1 mM) applied in vines increased grape amino acid concentration.•At harvest, the content of five anthocyanins was affected by riboflavin application.•Grape anthocyanins content decreased after one week of blue-light irradiation.
BACKGROUND AND AIMS: The antiseptic effect of the addition of colloidal silver (CAgC) alone or in combination with a small quantity of sulfur dioxide (SO₂) was examined in both vinification and ...storage of red wines. METHODS AND RESULTS: Four treatments of grapes and wines with SO₂ and CAgC alone or in combination with a small quantity of SO₂ were established. All treatments of grapes provided similar control of yeast and lactic acid bacteria, however, the three treatments with CAgC were more effective in the control of acetic acid bacteria. The addition of CAgC did not affect fermentation, and the wines had physicochemical, aromatic and sensory characteristics similar to that of the control, but a lower alcohol content. None of the treatments maintained control of bacteria during storage. After 1 month of stabilisation and 4 months of storage, the wines produced with CAgC had a higher colour intensity and a lower concentration of both anthocyanins and total polyphenols. Moreover, the final wines showed little difference in volatile and biogenic amine composition, which affected neither their quality nor their sensory characteristics. CONCLUSIONS: Under the conditions studied, addition of SO₂ could be reduced or replaced by CAgC. Overall, wines elaborated with CAgC showed no microbiological problems, and moreover, they had a higher colour intensity and similar aromatic composition and biogenic amines concentration to that of the control; their sensory characteristics were well rated. SIGNIFICANCE OF THE STUDY: Colloidal silver could be a promising antiseptic in the elaboration and storage of young wines.
•The effect of elicitation on grape volatile composition had been little studied.•3 elicitors were assayed: methyl jasmonate-MeJ, chitosan-CHT, a yeast extract-YE.•Sum of terpenes, ...C13-norisoprenoids, benzenoids and esters was the lowest in MeJ and CHT.•Total C6 compounds content in grapes treated with MeJ and CHT was the highest.•YE application scarcely affected volatile compounds respect to control samples.
Elicitors play a key role against pathogen infestation, becoming as an alternative to chemical pesticides by the improving secondary metabolites synthesis. Their effect on grape volatile compounds has been little investigated. This field trial aimed to study the foliar application of methyl jasmonate (MeJ), chitosan (CHT), and a yeast extract (YE) on grape volatile compounds by HS-SPME-GC–MS. The results showed that, in general, foliar elicitor application decreased the synthesis of grape volatile compounds. Depending of the treatment, MeJ and CHT showed the lowest total amounts of terpenoids, C13 norisoprenoids, benzenoids, and esters, together with the highest levels of C6 compounds. YE treatment applied to the grapevines barely affected the synthesis of volatile compounds in grapes. The importance of this work is to add information about the effects of elicitors on grape volatile composition in Tempranillo grapevines.
The effects of foliar application of methyl jasmonate and methyl jasmonate plus urea on the amino acids content of Tempranillo grapes were evaluated during two seasons (2019 and 2020). In 2019, the ...foliar treatments favored an increase in ammonium nitrogen (N), amino N and yeast assimilable N when compared to the control grapes; whereas, in 2020, treatments did not affect N parameters in grapes. In 2019, foliar application of both treatments was effective in improving amino acids content in grapes, being significantly higher the effect of methyl jasmonate plus urea treatment than methyl jasmonate treatment. However, in 2020, the effect of both treatments on amino acid content was minor. The different effect among seasons could be explained by environmental conditions and by the differences in N content in grapevines. A multifactorial analysis and discriminant study were carried out, showing that both treatments enhanced amino acid content in grapes. The effect of methyl jasmonate plus urea was stronger than the effect of methyl jasmonate treatment. Also, a great effect of season on amino acids composition was observed.
A study in order to differentiate Tempranillo and Tempranillo blanco grapes and wines from A.O.C. Rioja (Spain) has been carried out. The three most important groups of chemical compounds in grapes ...and wines were determined: nitrogen and phenolic compounds by HPLC–DAD, and volatile compounds by GC–MS. A machine learning approach was carried out to achieve the most important chemical parameters to differentiate Tempranillo and Tempranillo blanco grapes and wines based on the Kruskal–Wallis test, F-score feature selector, and support vector machine classification. Four importance levels were established for both grape and wine discrimination. The first level is composed of variables that can differentiate Tempranillo and Tempranillo blanco grapes and wines by analyzing the chemical concentrations. The second, third, and fourth level of importance is composed of a variable set that can correctly classify the samples, each one determined according to the F-score importance ranking and the SVM discriminations. Some chemical compounds demonstrated to be good predictors to wine and grape discriminations, whereas some chemicals are only a good predictor to one discrimination approach.
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