M. Figueiredo-González

The phenolic chemistry and spectrochemistry of red sweet wine-making and oak-aging.

A natural sweet wine (NSW) was made with dried grapes from Vitis vinifera L. cv Garnacha Tintorera. A fortified sweet wine (FSW) was also obtained: the maceration-alcoholic fermentation of Garnacha Tintorera must was stopped by addition of ethanol 96% (v/v). UV/Vis spectrophotometry and HPLC/DAD-ESI/MS were applied to determine, respectively, the evolution of colour and phenolic compounds in Garnacha Tintorera based-sweet wines during aging. In sweet wines, aging decreased a(∗) (red/green), colour saturation and lightness and increased b(∗) (yellow/blue), and hue angle. Most of the phenolic compounds determined, such as anthocyanins, esters of hydroxycinnamic acids, flavan-3-ols monomers, oligomers and polymers decreased in both sweet wines during aging. On the contrary, hydroxybenzoic and hydroxycinnamic acids and vitisins increased after one year of aging. Despite that both terminal and extension subunit compositions show very small changes, mean degree of polymerisation of proanthocyanidins decline slightly as aging progressed in both sweet wines.

Garnacha Tintorera-based sweet wines: chromatic properties and global phenolic composition by means of UV-Vis spectrophotometry.

Valdeorras (the N.W. corner of Spain) wants to promote the production and marketing of new sweet wines. The present work represents the first study on sweet wines manufactured with red grapes Vitis vinifera L. Garnacha Tintorera, a teinturier cultivar. Two different red sweet wines were elaborated: the first one was made with dried grapes; Vitis vinifera L. Garnacha Tintorera has excellent potential to produce wines from raisined grapes; the second one, a fortified sweet wine aged in oak barrels. Different red Garnacha Tintorera-based wines (a dry base wine, GBW; a naturally sweet wine, GNSW; and a fortified sweet wine, GFSW) were characterized. Chromatic characteristics and phenolic compounds were established by spectrophotometric methods in order to assess the technology of Garnacha Tintorera-based sweet wines. High molecular weight brown polymers, produced during the grape drying process and isolated from sweet wines by the dialysis process, were responsible for the brown colour of sweet wines. As a consequence, yellowness of sweet wines was also higher which was confirmed by colorimetric indexes. With respect to phenolic content, GFSW presented the lowest content because the maceration-alcoholic fermentation was stopped through the addition of alcohol before the diffusion of red pigments from skins to must was complete. GNSW presented the highest phenolic content due to the concentration effect resulting from evaporation of water from the grapes. Anthocyanins of sweet wines were polymerised in great extent. The percentage of polymerised tannins was sufficient to guarantee the aging process of sweet wines.

Garnacha Tintorera-based sweet wines: detailed phenolic composition by HPLC/DAD-ESI/MS analysis.

Sweet wines are traditionally elaborated in Galicia (the N.W. corner of Spain). The denomination of origin (DO) Valdeorras, one of the five DOs in Galicia, wants to promote the production and marketing of new sweets wines. The first one is made with dried red grapes Vitis vinifera L. Garnacha Tintorera (GNSW); this cultivar is a teinturier cultivar which has excellent potential to produce wines from raisined grapes. The second one, a fortified sweet wine aged in oak barrels (GFSW). Additionally a dry young wine (GBW) was produced from the same variety. Their aroma profiles and chromatic characteristics (determined by simple spectrophotometric methods) have been previously established. Now, proanthocyanidins, flava-3-ol monomers, anthocyanins, phenolic acids, flavonols and resveratrol were determined by HPLC, for the same three wines. The highest concentration of total proanthocyanidins (PAs) was evaluated in the GBW (525mgL(-1)), which was about 2-fold the concentration in the GNSW (236mgL(-1)) and about more 10-fold the concentration in the GFSW (44mgL(-1)). No apparent difference in the aDP (mean degree of polymerisation) was observed for the GBW (1.9) and the GNSW (2.1), whereas a slightly lower value was obtained for the GFSW (1.5). Total anthocyanin concentration was described as follow as GBW: 390mgL(-1)≫GNSW: 57mgL(-1)>GFSW: 25mgL(-1), which indicates that sweet wines were polymerised in great extent. Only vitisin A and B were found the main concentration in GFSW when compared to GBW by the ageing process. In sweet wines, phenolic acids (hydroxybenzoic and hydroxycinnamic acids) and flavonols were lowest when compared to GBW and resveratrol not was found in sweet wines.

Evolution of colour and phenolic compounds during Garnacha Tintorera grape raisining.

The off-vine drying is one of the most important steps in the production of a high quality naturally sweet wine. However, only few studies have analyzed the changes in colour and phenolic compounds of the grapes throughout the process. In this work, UV/Vis spectrophotometry and HPLC/DAD-ESI/MS were applied to determine, respectively, the evolution of colour and phenolic compounds in the red grapes of Garnacha Tintorera during the raisining process. The total water loss in 83 days was about 62% and the sugar concentration rose from 225 to 464 g L(-1). Browning and low-medium molecular weight compounds increase during the dehydration process. In CIELab coordinates, raisining decreases a(*) (red/green) and lightness and increases b(∗) (yellow/blue), colour saturation and hue angle. In general, most of the phenolic compounds determined (anthocyanins, flavonols, esters of hydroxycinnamic acids, flavan-3-ol monomers and proanthocyanidins) increase but to a lesser extent than expected because of the water loss of the grapes during drying. The lower increase was observed for esters of hydroxicinnamic acids suggesting these compounds could undergo strong enzymatic degradation. Despite this, both the terminal and the extension subunit compositions show little changes, while the mean degree of polymerization of proanthocyanidins decreases as raisining progresses.

Evolution of flavonoids in Mouratón berries taken from both bunch halves

Galicia (N.W. Spain) is a Spanish region with several old-traditional winegrowing areas. There are autochthonous grapevine varieties, such as Vitis vinifera L. cv. Mouratón, considered a biodiversity resource in viticulture and an opportunity for Galician sustainable wine production. Therefore, it is necessary to assess the potential of traditional cultivars to produce quality red wines. In this work, anthocyanin and flavonol evolution was followed in red berries from V. vinifera L. cv. Mouratón. The novelty of this study is that grapes were separately collected from two different positions (tips and shoulders) within the cluster, over ripening to examine the effects of berry position within the fruit cluster on the flavonoid compounds. Derivatives of five anthocyanins (malvidin, peonidin, petunidin, delphinidin and cyanidin) and derivatives of six flavonols (quercetin, myricetin, kaempherol, laricitrin isorhamnetin and syringetin) were detected in both positions within the cluster. Dynamic of anthocyanins (from 819 mg/kg to 1206 mg/kg in tips; and from 786 mg/kg to 1077 mg/kg in shoulders) and dynamic of flavonols (from 25mg/kg to 41 mg/kg in tips; and from 18 mg/kg to 21 mg/kg in shoulders) confirmed their upward trends over ripening. Grapes located inside the shoulder bunch receive less sunlight radiation than those located inside the tip bunch and this fact could explain the different accumulation observed for both positions. These results can be useful for winemakers in order to obtain different final red wine quality.

State of the Art on Functional Virgin Olive Oils Enriched with Bioactive Compounds and Their Properties

Virgin olive oil, the main fat of the Mediterranean diet, is per se considered as a functional food—as stated by the European Food Safety Authority (EFSA)—due to its content in healthy compounds. The daily intake of endogenous bioactive phenolics from virgin olive oil is variable due to the influence of multiple agronomic and technological factors. Thus, a good strategy to ensure an optimal intake of polyphenols through habitual diet would be to produce enriched virgin olive oil with well-known bioactive polyphenols. Different sources of natural biological active substances can be potentially used to enrich virgin olive oil (e.g., raw materials derived from the same olive tree, mainly olive leaves and pomaces, and/or other compounds from plants and vegetables, mainly herbs and spices). The development of these functional olive oils may help in prevention of chronic diseases (such as cardiovascular diseases, immune frailty, ageing disorders and degenerative diseases) and improving the quality of life for many consumers reducing health care costs. In the present review, the most relevant scientific information related to the development of enriched virgin olive oil and their positive human health effects has been collected and discussed.

Effect of Two Anti-Fungal Treatments (Metrafenone and Boscalid Plus Kresoxim-methyl) Applied to Vines on the Color and Phenol Profile of Different Red Wines

The effect of two anti-fungal treatments (metrafenone and boscalid + kresoxim-methyl) on the color and phenolic profile of Tempranillo and Graciano red wines has been studied. To evaluate possible modifications in color and phenolic composition of wines, control and wines elaborated with treated grapes under good agricultural practices were analyzed. Color was assessed by Glories and CIELab parameters. Color changes were observed for treated wines with boscalid + kresoxim-methyl, leading to the production of wines with less color vividness. Phenolic profile was characterized by HPLC analysis. Boscalid + kresoxim-methyl treatment promoted the greatest decrease on the phenolic content in wines.

Nutraceutical Potential of Phenolics from ′Brava′ and ′Mansa′ Extra-Virgin Olive Oils on the Inhibition of Enzymes Associated to Neurodegenerative Disorders in Comparison with Those of ′Picual′ and ′Cornicabra′

The increasing interest in the Mediterranean diet is based on the protective effects against several diseases, including neurodegenerative disorders. Polyphenol-rich functional foods have been proposed to be unique supplementary and nutraceutical treatments for these disorders. Extra-virgin olive oils (EVOOs) obtained from ′Brava′ and ′Mansa′, varieties recently identified from Galicia (northwestern Spain), were selected for in vitro screening to evaluate their capacity to inhibit key enzymes involved in Alzheimer′s disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (5-LOX)), major depressive disorder (MDD) and Parkinson′s disease (PD) (monoamine oxidases: hMAO-A and hMAO-B respectively). ′Brava′ oil exhibited the best inhibitory activity against all enzymes, when they are compared to ′Mansa′ oil: BuChE (IC50 = 245 ± 5 and 591 ± 23 mg·mL−1), 5-LOX (IC50 = 45 ± 7 and 106 ± 14 mg·mL−1), hMAO-A (IC50 = 30 ± 1 and 72 ± 10 mg·mL−1) and hMAO-B (IC50 = 191 ± 8 and 208 ± 14 mg·mL−1), respectively. The inhibitory capacity of the phenolic extracts could be associated with the content of secoiridoids, lignans and phenolic acids.

The involvement of phenolic-rich extracts from Galician autochthonous extra-virgin olive oils against the α-glucosidase and α-amylase inhibition

Brava and Mansa de Figueiredo extra-virgin olive oils (EVOOs) are two varieties identified from north-western Spain. A systematic phenolic characterization of the studied oils was undertaken by LC-ESI-IT-MS. In addition, the role of dietary polyphenols from these EVOOs has been evaluated against the inhibition of key enzymes (α-glucosidase and α-amylase) in the management of diabetes mellitus (DM). Oleuropein and ligstroside derivatives comprised 83% and 67% of the total phenolic compounds in Brava and Mansa de Figueiredo EVOOs, respectively. The main secoiridoids from oleuropein were DOA (3,4-DHPEA-EDA, 59 and 22u202fmgu202fkg-1, respectively) and the main isomer of OlAgl (3,4-DHPEA-EA, 74 and 23u202fmgu202fkg-1). The main secoiridoids from ligstroside were D-LigAgl (p-HPEA-EDA or oleocanthal, 23 and 167u202fmgu202fkg-1) and the main isomer of LigAgl (p-HPEA-EA, 214 and 114u202fmgu202fkg-1). For α-glucosidase, both EVOO extracts displayed stronger inhibitory activity (IC50 values of 60u202f±u202f8 and 118u202f±u202f9u202fμgu202fmL-1, respectively) than the commercial inhibitor acarbose (IC50u202f=u202f356u202f±u202f21u202fμgu202fmL-1). Nevertheless, for α-amylase, only Brava extracts showed anti-α-amylase capacity. A daily VOO intake lower than the requirements of EFSA seem to be enough to reach both 50% for α-glucosidase and 25% for α-amylase inhibition. These findings support the potential health benefits derived from Galician EVOOs that might be probably linked to the outstanding high concentration levels of phenolic acids and flavonoids.