Characterization of phenolic composition in Carignan noir grapes (Vitis vinifera L.) from six wine-growing sites in Maule Valley, Chile

High-Resolution Mass Spectrometry-Based Metabolomics for Increased Grape Juice Metabolite Coverage

The composition of the juice from grape berries is at the basis of the definition of technological ripeness before harvest, historically evaluated from global sugar and acid contents. If many studies have contributed to the identification of other primary and secondary metabolites in whole berries, deepening knowledge about the chemical composition of the sole flesh of grape berries (i.e., without considering skins and seeds) at harvest is of primary interest when studying the enological potential of widespread grape varieties producing high-added-value wines. Here, we used non-targeted DI-FT-ICR-MS and RP-UHPLC-Q-ToF-MS analyses to explore the extent of metabolite coverage of up to 290 grape juices from four Vitis vinifera grape varieties, namely Chardonnay, Pinot noir, Meunier, and Aligoté, sampled at harvest from 91 vineyards in Europe and Argentina, over three successive vintages. SPE pretreatment of samples led to the identification of more than 4500 detected C,H,O,N,S-containing elemental compositions, likely associated with tens of thousands of distinct metabolites. We further revealed that a major part of this chemical diversity appears to be common to the different juices, as exemplified by Pinot noir and Chardonnay samples. However, it was possible to build significant models for the discrimination of Chardonnay from Pinot noir grape juices, and of Chardonnay from Aligoté grape juices, regardless of the geographical origin or the vintage. Therefore, this metabolomic approach opens access to a remarkable holistic molecular description of the instantaneous composition of such a biological matrix, which is the result of complex interplays among environmental, biochemical, and vine growing practices.

Leaf Removal at Véraison and Foliar K+ Application to Beibinghong Vines Improved Berry Quality under Cold-Climate Conditions

(1) Background: Beibinghong is a grapevine variety that is well distributed in Northeastern China due to its adaptation to extreme cold conditions and vine diseases. Nonetheless, Beibinghong wines are extremely acidic and rich in phenolic compounds. The aim of this research was to study the effects of leaf removal at véraison and foliar K+ applications on Beibinghong vines to reduce the acidity and increase their polyphenol content. (2) Methods: Beibinghong berries were harvested when they reached close to 20 °Brix, and the physicochemical parameters were determined. (3) Results: Leaf removal at véraison plus K+ foliar applications to Beibinghong vines decreased the titratable acidity and increased the total phenolic and phenolic acid contents compared with the control. Moreover, the titratable acidity in the Beibinghong berries was negatively related to their total contents of phenols, proanthocyanidins, and anthocyanins. (4) Conclusions: Leaf removal at véraison performed with foliar K+ applications to vines could be an interesting alternative for Beibinghong production under cold-climate viticulture because it allows for a decrease in the acidity and an increase in the phenolic content of the berries, without incurring the risk of sunburn.

Climate Change Effects on Grapevine Physiology and Biochemistry: Benefits and Challenges of High Altitude as an Adaptation Strategy

Grapevine berry quality for winemaking depends on complex and dynamic relationships between the plant and the environment. Winemakers around the world are demanding a better understanding of the factors that influence berry growth and development. In the last decades, an increment in air temperature, CO₂ concentration and dryness occurred in wine-producing regions, affecting the physiology and the biochemistry of grapevines, and by consequence the berry quality. The scientific community mostly agrees in a further raise as a result of climate change during the rest of the century. As a consequence, areas most suitable for viticulture are likely to shift into higher altitudes where mean temperatures are suitable for grape cultivation. High altitude can be defined as the minimum altitude at which the grapevine growth and development are differentially affected. At these high altitudes, the environments are characterized by high thermal amplitudes and great solar radiations, especially ultraviolet-B (UV-B). This review summarizes the environmental contribution of global high altitude-related climatic variables to the grapevine physiology and wine composition, for a better evaluation of the possible establishment of vineyards at high altitude in climate change scenarios.

Correlations between Total Antioxidant Capacity, Polyphenol and Fatty Acid Content of Native Grape Seed and Pomace of Four Different Grape Varieties in Hungary

Grape pomace is a valuable source of various bioactive compounds such as plant-derived polyphenols and polyunsaturated fatty acids (PUFAs). The commercial demand of grape skin and seed powders as nutraceuticals is still growing. However, no distinction is currently made between unfermented native grape seed and grape seed pomace powders regarding their antioxidant activities. Our aim was to find the relationship between the polyphenol and fatty acid content as well as the antioxidant capacity of native and fermented grape seeds of four different grape varieties harvested in the Villány wine region. According to our results, none of the three investigated polyphenols (resveratrol, rutin, quercetin) could be detected in native grape seed samples in correlation with their significantly lower total antioxidant capacities compared to fermented seed samples. Pinot Noir (PN) grape seed pomace samples with the highest resveratrol and oil content showed significantly higher total antioxidant capacity than Cabernet Sauvignon (CS), Syrah (S) and Blue Portugal (BP) samples. Based on the statistical analysis, positive correlation was found between the fatty acid content and the resveratrol concentration in the pomace samples of different grape varieties. In contrast, rutin concentrations were negatively proportional to the fatty acid content of the fermented samples. No significant correlation was found considering the quercetin content of the samples. According to our findings, grape pomace seems a more promising source in the production of nutraceuticals, since it contains polyphenols in higher concentration and exerts significantly higher antioxidant activity than native grape seeds.

Influence of seaweed foliar application to Tempranillo grapevines on grape and wine phenolic compounds over two vintages

The study of seaweeds is increasing in viticulture due to their implications on plant protection and grape quality. This trial aimed to study the effects of foliar applications of an Ascophyllum nodosum extract at low (0.25%, v v-1) and high (0.50%, v v-1) dosages on grape and wine phenolic compounds in 2017 and 2018. In grapes, seaweed biostimulation increased the content of malvidin-3-glc, myricetin-3-glc and myricetin-3-gal in 2017 season. Moreover, both treatments improved the synthesis of trans-piceid and total stilbenes in both seasons. Sensory analysis revealed that 2017 wines had more color than the 2018 wines, which coincided with color intensity parameters. Therefore, seaweed applications to grapevines improved stilbenes content in grapes independently of the season and its effects on the rest of phenolic compounds in grapes and wines depended strongly of season factor.

Strategies in vineyard establishment to face global warming in viticulture: a mini review

Different technological solutions are developing in the wine industry to mitigate the negative effects of the current global warming to mainly achieve wines with a lower alcohol content. These proposed solutions mostly act at the oenological level and are focused on intervening in the raw material to be transformed; that is, on reducing the concentration of sugar in the must using filtration techniques or also on wine dealcoholizing by physical processes. These techniques are intended to offer solutions and respond to new consumer expectations, but they may be considered too artificial to be widely accepted. In this way, viticultural strategies may offer a natural solution to obtain grapes with low sugar content, maximizing their quality by delaying ripening. This mini review surveys the viticultural strategies that can be applied in the establishment of a vineyard - that is, when it comes to planting of a new vineyard - such as vineyard altitude, latitude, orientation, and slope, as well as rootstock, variety, clone, training system, and row orientation and slope, with the aim to mitigate the negative effects of climate change on grape and wine quality and to delay grape maturation. Finally, we propose a ponderation of the strategies discussed to contextualize its importance to face global warming in viticulture. © 2020 Society of Chemical Industry.

Terroir and vintage discrimination of Malbec wines based on phenolic composition across multiple sites in Mendoza, Argentina

This study evaluated the phenolic profiles of Malbec wines made from grapes of 23 parcels distributed in 12 geographical indications (GIs) from Mendoza, Argentina. Wines were elaborated under standardized winemaking conditions over three consecutive vintages (2016–2018). Data discriminated wines from different GIs and parcels, based on an integrative data analysis by chemometric tools. Vintage effect and specific phenolic compounds were associated with some GIs or parcels. As well, regional climate conditions allowed partial discrimination of the GIs (and also some parcels). A random forest analysis correctly identified 11 out of 23 individual parcels across the different vintages. The most notorious compounds associated with such classification were p-coumaric acid, delphinidin-3-O-glucoside, caffeic acid, quercetin and peonidin-3-O-glucoside. The presented research allows to individualize, through phenolic profiles, parcels with unique characteristics over years. This is the first report characterizing Malbec wines coming from several GIs (and individual parcels) in different vintages. These results are strongly related to terroir features of wines, contributing to a better communication to consumers and to position Argentinean wines.

Extended Harvest Date Alter Flavonoid Composition and Chromatic Characteristics of Plavac Mali (Vitis vinifera L.) Grape Berries

This study delivers a comprehensive flavonoid fingerprint profile, physiochemical and external color characterization of Plavac Mali grapes through four harvest dates at two distinct vineyards (Split and Zadar) in the Eastern Adriatic region. The experimental harvest lasted 56 days, at total soluble solids content from 18.4 to 22.4°Brix in Split and 16.8 to 20.4°Brix in Zadar. Patterns of 27 skin and seed flavonoid compounds at each location indicate unique flavonoid composition of berries at each harvest date. Extended harvest increased six compounds in skin with maximum values of main anthocyanin malvidin-3-O-glucoside in H3 (4406.6 and 6389.5 mg kg⁻¹, Split and Zadar, respectively) followed by a decrease in October. Peak values of seed and skin catechins and galloylated flavan-3-ol subunits are seen in H1 and H2 at Split, while constantly high values are reported in the case of Zadar, with an incoherent pattern of those in skin extracts. Minimal values of epigallocatechin were detected with an extended harvest date at both locations. Berries of extended harvest dates underwent colorimetric improvements, trough decrease in L*, a*, b* and C characteristics and increase in skin color index for red grapes CIRG. The extended harvest date promotes flavonoid composition, and improves the quality of Plavac Mali grape berries.

Oenological potential and health benefits of Chinese non-Vitis vinifera species: An opportunity to the revalorization and to breed new varieties

The wine industry is focused on the producing wine mostly from European grapevine varieties (Vitis vinifera L.). China has experienced a significant growth of the vineyard surface, based on the cultivation of these grapevine varieties. Currently, China has become one of the countries with the largest surface of planted vineyards in the world. In the last years, there has been a trend to oenologically and viticulturally revalorize certain autochthonous grapevine species. China holds a great diversity of Vitis species, which are being the focus of study. This could be an important alternative for the diversification of wine production, providing new products with a strong identity. Additionally, the varietal homogenization has increased the vineyard genetic vulnerability in relation to the emergence of grapevine diseases and their resistance to chemical fungicides. In this way, non-Vitis vinifera species are characterized by having a high resistance to a wide range of biotic and abiotic factors, which can bring an opportunity to breed new varieties. However, there is little available information about the oenological potential of these species, which makes it a current interesting topic. Therefore, this review aims to summarize the oenological potential of non-Vitis vinifera species found in China, discussing their potential effects on human health and thus, to propose some Chinese wild grapes for their use in breeding programs.

Alternative Woods in Enology: Characterization of Tannin and Low Molecular Weight Phenol Compounds with Respect to Traditional Oak Woods. A Review

Wood is one of the most highly valued materials in enology since the chemical composition and sensorial properties of wine change significantly when in contact with it. The need for wood in cooperage and the concern of enologists in their search for new materials to endow their wines with a special personality has generated interest in the use of other Quercus genus materials different from the traditional ones (Q. petraea, Q. robur and Q. alba) and even other wood genera. Thereby, species from same genera such as Q. pyrenaica Willd., Q. faginea Lam., Q. humboldtti Bonpl., Q. oocarpa Liebm., Q. stellata Wangenh, Q. frainetto Ten., Q. lyrata Walt., Q. bicolor Willd. and other genera such as Castanea sativa Mill. (chestnut), Robinia pseudoacacia L. (false acacia), Prunus avium L. and P. cereaus L. (cherry), Fraxinus excelsior L. (European ash) and F. americana L. (American ash) have been studied with the aim of discovering whether they could be a new reservoir of wood for cooperage. This review aims to summarize the characterization of tannin and low molecular weight phenol compositions of these alternative woods for enology in their different cooperage stages and compare them to traditional oak woods, as both are essential to proposing their use in cooperage for aging wine.

Resurgence of minority and autochthonous grapevine varieties in South America: a review of their oenological potential

In contrast with the general trend of producing wine from the most famous grapevine varieties, associated with the French paradigm, such as Cabernet-Sauvignon, Merlot, Pinot Noir, Syrah, Sauvignon Blanc, and Chardonnay, there is a tendency to revalorize and preserve minority or autochthonous grapevine varieties worldwide. The South American wine region, where most of the varieties derived from varieties brought after European colonization, is not exempt from this. This has allowed new wines to be provided with distinctive identities that are markedly different from the current homogeneous wine production. Moreover, varietal homogenization increases vineyard genetic vulnerability in relation to the emergence of grapevine diseases, to which the commonly cultivated varieties are not resistant. This review summarizes the oenological potential of minority or autochthonous grapevine varieties cultivated within the South American wine region, focusing on Argentina, Chile, and Bolivia. © 2019 Society of Chemical Industry.

Optimization of a polyphenol extraction method for sweet orange pulp (Citrus sinensis L.) to identify phenolic compounds consumed from sweet oranges

The consumption of sweet oranges has been linked to several health benefits, many of which are attributed to hesperidin, a flavanone that is present in high amounts in these fruits. However, other phenolic compounds can contribute to the bioactivity of sweet orange. To link those effects to their phenolic profile, the complete characterization of the phenolic profile is mandatory. Although many studies have profiled the phenolic composition of orange juices, their pulps, which retain phenolic compounds, are overlooked. This fact is particularly relevant because dietary guidelines recommend the consumption of whole fruits. Therefore, this study aimed to develop a specific method for the optimal extraction of phenolics from orange pulp and to use this method to characterize these fruits grown at different locations by HPLC-ESI-MS/MS. The extraction conditions that reported the highest total polyphenol content (TPC) and hesperidin contents were 20 mL/g, 55 °C, and 90% methanol. The extraction time and number of sequential steps were further evaluated and optimized as 20 min and two extraction steps, respectively. Although lower extraction rates were achieved when using ethanol as the extraction solvent, high TPC and hesperidin yields were obtained, suggesting the potential use of this methodology to produce phenolic-rich extracts for the food industry. By applying the optimized methodology and analyzing the extracts by HPLC-ESI-MS/MS, geographic cultivation regions were demonstrated to affect the phenolic profiles of oranges. In short, we developed a quick, easy-to-perform methodology that can be used to extract orange phenolics from pulp for their identification and quantification and to evaluate the factors that affect the phenolic profile in sweet orange pulps.

Optimized Extraction by Response Surface Methodology Used for the Characterization and Quantification of Phenolic Compounds in Whole Red Grapes (Vitis vinifera)

Scientific research has focused on the characterization of bioactive polyphenols from grape seeds and skins, and the pulp has often been overlooked. However, since the beneficial properties of grapes are associated with the consumption of whole fruit, a full extraction and posterior characterization of the phenolic compounds in whole grapes is required to identify the involved bioactive compounds. Such methodologies are not currently available for the whole edible parts of red grapes. This study aimed to determine the best polyphenol extraction conditions of whole red grapes, and apply the method to characterize and quantify the polyphenol composition of three different grapes. The optimized conditions were 80 mL/g, 65% methanol (1% formic acid), 72 °C, and 100 min under agitation of 500 rpm. Also, methanol and ethanol were compared as extraction solvents, and methanol achieved statistically higher extraction rates for anthocyanins. The results of this work suggest a higher quantification of phenolic compounds when red grapes are analyzed whole, including the seeds, pulp, and skin.

Volatile composition of Carignan noir wines from ungrafted and grafted onto País (Vitis vinifera L.) grapevines from ten wine-growing sites in Maule Valley, Chile

BACKGROUND

Carignan noir is one of the minor and ancient varieties from the Chilean wine scenario that has had a resurgence as a result of to its rediscovered oenological potential when cultivated under the conditions of the interior dryland area. Under these growing conditions Carignan noir wines stand out as fruit driven and fresh compared to those originating from other growing areas. On the other hand, it is well known that wine aroma composition depends mainly on variety, viticultural management and winemaking. Thus, the present study aimed to investigate the volatile composition of wines from Carignan noir grapes originating from ungrafted and grafted onto País grapevines, in ten sites of the Maule Valley (Chile) during two consecutive vintages.

RESULTS

Higher alcohols were the most abundant volatile compounds, whereas ethyl esters and ß-damascenone were the most odoriferous compounds according to their odorant activity value. The dominant factor in Carignan noir wine volatile composition was season, whereas rootstock did not have a significant effect in differentiating the wines. In terms of climate, cold nights during the month prior to harvest correlated with higher linalool, α-terpineol and trans-3-hexen-1-ol content. The biologically effective degree-days index was inversely correlated with isoamyl acetate and 2-phenylethyl acetate content. Huglin's heliothermal and the average mean temperature of the warmest month indices were inversely correlated with ethyl vanillate, ethyl hexanoate and ethyl octanoate content.

CONCLUSION

Site climate conditions were related to the accumulation of certain wine volatile compounds. This information may be useful for devising new Carignan noir vineyard management strategies when aiming to improve wine quality or adjust site selection approaches to maximize grape/wine volatile composition according to wine style. © 2018 Society of Chemical Industry.

Grape and wine amino acid composition from Carignan noir grapevines growing under rainfed conditions in the Maule Valley, Chile: Effects of location and rootstock

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.