Aging of red wines made from hybrid grape cv. BRS Violeta: Effects of accelerated aging conditions on phenolic composition,color and antioxidant activity

Aging is an enological technique usually employed with Vitis vinifera wines for improving and stabilizing wine sensory attributes like red wine color. However, red wines made from non-vinifera grape cultivars are considered not suitable for classic wine aging because they are prone to color loss during processing and storage, mainly due to the major occurrence of non-acylated anthocyanidin 3,5-diglucosides. The recently developed hybrid grape cv. BRS Violeta gives rise to deep red-purplish colored wines characterized by an important contribution of p-coumaroylated anthocyanidin 3,5-diglucosides. In this work, Violeta red wines were subjected to control (storage at 15 °C) and accelerated (storage at 25, 35 and 50 °C) aging for 120 days. Total phenolic content was only significantly decreased by 23% in accelerated aged wines at 50 °C, whereas antioxidant capacity was mainly reduced in the first 20 days of aging (around 35% for all the wines, except for 45% for wine aged at 50 °C) and then remained almost stable. In contrast, total anthocyanin content decreased following expected first-order kinetics and the variation of rate constants with regard to temperature fitted well with an Arrhenius-type equation. The calculated activation energy for disappearance of anthocyanins (47 kJ/mol) was close to the lower limit of the range of values reported for thermal degradation of anthocyanidin 3-glucosides. In addition, half-life values for p-coumaroylated anthocyanidin 3,5-glucosides of Violeta wine aged at 50 °C almost doubled those of their corresponding non-acylated derivatives. The latter result is suggested to be the main reason behind the relatively high resistance of Violeta wine towards the disappearance of anthocyanin under accelerated aging conditions. Finally, chromatic characteristics of Violeta wines did not significantly change their C* values during aging but L* and h* values increased as expected, the latter mainly due to higher increases of the yellow color component (b*) over lower decreases of the red color component (a*). These color changes were more drastic in the accelerated aged wines and the wine aged at 25 °C still maintained interesting color characteristics close to those of the control aged wine that did not change very much.     

Effect of high pressure treatments on the physicochemical properties of a sulphur dioxide-free red wine

The application of high hydrostatic pressure (HHP) in winemaking for substitution of the use of sulphur dioxide is still at a very early stage of development, since knowledge about the effect on physicochemical and sensorial characteristics of the wine during storage is very scarce. In this work, the evolution of colour, antioxidant activity and total phenolic compounds of SO₂-free red wines treated by HHP and aged in bottles was followed for 12 months. The pressurised wines were compared with wine samples prepared with addition of 40 ppm of SO₂ and without any of these two treatments. After 12 months, the pressurised wines presented higher values of CIELab parameters (a^∗, b^∗, and L^∗) and a lower monomeric anthocyanin content (45–61%) when compared to the unpressurised ones. The pressurised wines showed also a better global sensorial assessment, with the pressure treatments imparting aged-like characteristics to the wines. The wine deposits of pressurised wines had higher total phenolic content, namely proanthocyanidins (3- to 10-fold). The results demonstrate that HHP can influence long term red wine physicochemical and sensorial characteristics, hypothesised to be due to an increase of condensation reactions of phenolic compounds, forming compounds with higher degree of polymerisation that became insoluble in wine along storage.     

Improvement of winemaking process using pulsed electric fields at pilot-plant scale. Evolution of chromatic parameters and phenolic content of Cabernet Sauvignon red wines

The influence of the application of a continuous pulsed electric fields treatment (PEF treatment) to grape pomace on the evolution of colour and phenolic content of Cabernet Sauvignon red wines has been investigated. Wine from grape treated by PEF presented at the end of alcoholic fermentation higher colour intensity (CI), total polyphenol index (TPI) and total anthocyanic content (TAC) than control wine. This effect was observed even although maceration time for PEF wine was 48 h shorter than for control. Differences remained during malolactic fermentation and maturation. After 4 months of aging in bottle, CI, TPI and TAC of PEF wine were 38%, 22% and 11% higher respectively than the control. HPLC phenolic profiles of wines were qualitatively similar, without detecting a selective effect on any phenol. No significant differences in sensory attributes between wines were detected. Results indicate that PEF is a promising technology in red winemaking for reducing the maceration time and increasing colour and phenolic extraction.     

Influence of the temperature and oxygen exposure in red Port wine: A kinetic approach

Although phenolics are recognized to be related with health benefits by limiting lipid oxidation, in wine, they are the primary substrates for oxidation resulting in the quinone by-products with the participation of transition metal ions. Nevertheless, high quality Port wines require a period of aging in either bottle or barrels. During this time, a modification of sensory properties of wines such as the decrease of astringency or the stabilization of color is recognized to phenolic compounds, mainly attributed to anthocyanins and derived pigments.The present work aims to illustrate the oxidation of red Port wine based on its phenolic composition by the effect of both thermal and oxygen exposures. A kinetic approach toanthocyanins degradation was also achieved. For this purpose a forced red Port wine aging protocol was performed at four different storage temperatures, respectively, 20, 30, 35 and 40 °C, and two adjusted oxygen saturation levels, no oxygen addition (treatment I), and oxygen addition (treatment II). Three hydroxycinnamic esters, three hydroxycinnamic acids, three hydroxybenzoic acids, two flavan-3-ols, and six anthocyanins were quantitated weekly during 63 days, along with oxygen consumption. The most relevant phenolic oxidation markers were anthocyanins and catechin-type flavonoids, which had the highest decreases during the thermal and oxidative red Port wine process. Both temperature and oxygen treatments affected the rate of phenolic degradation. In addition, temperature seems to influence mostly the phenolics kinetic degradation.     

Sensory changes during bottle storage of Spanish red wines under different initial oxygen doses

Sixteen commercial Spanish red wines selected to cover a wide range of sensory properties were stored at 25 °C for 6 months in air-tight containers under different oxygen doses (0–30 mg L^− 1) mimicking real and extreme bottling situations. The 16 initial samples (before storage) and the 80 stored samples (16 wines × 5 oxygen doses) were submitted to sensory analysis. Sensory changes related to post-bottling storage and initial oxygen dose were evaluated by means of discriminant and characterisation sensory strategies.Significant increases in black fruits, dried fruits, woody, lactic and stronger increases in cooked vegetables and spicy notes reveal a general pattern of aroma evolution. Remarkable departures to this general pattern have been observed, which can be related to the initial sensory properties of the wines and to their basic polyphenolic composition. The effect of post-bottling storage in bitterness is wine dependent, while global decreases in both global intensity and persistence evaluated in mouth are observed. Discrete increases in astringency are observed for wines with the lowest initial astringent scores. Important sensory interactions between aroma attributes (herbal and spicy) and bitterness and between roasted and astringency perception are shown. Little impact of the initial oxygen dose in the in-mouth sensory properties is reported. These results are relevant for wine experts in that they help understanding the evolution of wine sensory properties in the bottling stage. This study may help them to develop strategies for managing this winemaking stage with objective criteria.     

High hydrostatic pressure treatment: An artificial accelerating aging method which did not change the region and variety non-colored phenolic characteristic of red wine

The effect of high hydrostatic pressure (HHP) treatment on the region and variety non-colored phenolic characteristics of red wine was investigated in this study. After HHP treatment, many changes occurred in the non-colored phenolic compounds in red wines. Changes in total phenolic acids and the contents of eleven phenolic acids among different regions and varieties varied and showed an overall upward trend, while chlorogenic acid decreased in several wines. The total flavan-3-ols and five flavan-3-ols largely decreased among the different regions and different varieties, while EGC slightly increased. In addition, HHP treatment did not change the grape variety and grape geographic origin discrimination based on phenolic acids and flavan-3-ols, which suggests that HHP treatment had no effect on the region and variety of non-colored phenolic characteristics of red wine. These results could expedite the use of HHP processing in the wine industry.Industrial relevanceHHP is an important technology which could simulate the traditional aging process in wine industry and could shorten a lot of time and save great economic costs. However, no HHP-treated wine has been introduced in the market throughout the world so far. This is due, in large part, to the lack of correlation studies. In this study, we proved that HHP didn't change grape variety and grape geographic origin phenolic characteristics, hence it could be used in geographic indication wines and varietal wines. With these results, we hope HHP technology could be successfully used in wine industry as early as possible.     

Effects of high hydrostatic pressure on the quality and shelf-life of jujube (Ziziphus jujuba Mill.) pulp

This study evaluated the effects of high hydrostatic pressure (HHP) on the microbial counts, physicochemical properties, bioactive compounds, and antioxidant capacity of jujube pulp. Additionally, this study compared the shelf life of jujube pulp following HHP (600 MPa/20 min) and thermal treatment (100 °C/10 min) during 40 days of storage at 4 °C and 15 °C. The microbial count of HHP-treated jujube pulp (≥ 400 MPa/20 min) was below the detection limit. Total soluble solids and total sugars were not significantly affected by HHP processing, and > 90% ascorbic acid was retained in HHP-treated samples. HHP slightly reduced pH and browning degree and increased total phenolic content, flavonoid content, and antioxidant capacity. HHP can be used as an alternative to thermal pasteurization of freshly squeezed jujube pulp.Industrial relevanceEffects of high hydrostatic pressure (HHP) processing and thermal treatment (TT) on microbiological quality, physicochemical properties, bioactive compounds and antioxidant activity in jujube pulp were investigated. Greater inhibition of microorganisms and better retention of ascorbic acid, total phenolics, flavonoid and antioxidant capacity were observed after HHP-treatment. The available data could be used to design the HHP parameters for high quality jujube juice. Further, this research would provide a useful method for preservation of jujube products and potential technical support for jujube commercial production.     

Enological tannins affect acetaldehyde evolution,colour stability and tannin reactivity during forced oxidation of red wine

The addition of enological tannins is a practice admitted and widely used to improve wine phenolic compositions. Although wine ageing is an oxidative process involving phenolic compounds and acetaldehyde production and consumption, the effect of enological tannins on the acetaldehyde and chromatic and phenolic changes of a red wine during oxidation is still not known. In this study, three enological tannins preparations containing gallotannins GT, ellagitannins ET and condensed tannins CT were added to a young commercial Lambrusco red wine in order to obtain wines with three different phenolic compositions. Samples were then treated with hydrogen peroxide to trigger oxidation. All added tannins have determined a production of acetaldehyde greater than control. Acetaldehyde was then consumed in 30 days. The samples treated with CT and ET showed, after oxidation, an increase in colour intensity, determined as the sum of 420, 520 and 620 nm absorbances. A simultaneously increase in polymeric pigments was detected. No significant variation of the Saliva Precipitation Index (SPI), an index useful to give an indirect measure of wine astringency, was observed after 30 days of treatment of CT and ET samples. Results highlight that the addition of CT and ET can help to stabilise colour without affecting wine reactivity towards salivary proteins. A significant role of acetaldehyde has been even detected. These are the first data showing the effect of different enological tannins on the production and consumption of acetaldehyde formation during an oxidation process.     

Effect of high hydrostatic pressure (HHP) on crystal structure of palm stearin emulsions

High hydrostatic pressure (HHP) treatment was used to control the crystallization behavior of solid lipid nanoparticles stabilized with sodium caseinate (SC) and soy lecithin Phospholipon 80H (80H). Samples were pressurized at 100 and 500 MPa, at 10, 20 and 40 °C for 15 min. The stability of emulsions was analyzed by visual observation for gelation, and the change in the droplet size distribution using light scattering measurements after HHP treatment and storage for 28 days at 4 °C. The crystal micro-structure (i.e., solid lipid content and crystal morphology) were evaluated from differential scanning calorimetry (DSC) thermograms for melting enthalpies and temperatures. Initial droplet size (0.199 μm for 80H and 0.182 μm for SC) was not affected significantly (p > 0.05) either by HHP processing or storage. DSC results showed that pressure has a significant effect (p < 0.05) on the crystal polymorphs contents. Change in polymorphic content due to HHP treatment was approximately 50% at the first day of storage for all samples. Storage time was also found to be significantly effective (p < 0.05) on polymorphic structure and the change in polymorphic content was approximately 46% throughout the storage period. It was shown that HHP treatment can be used to control the crystal morphology of crystalline lipid droplets, which can serve as potential encapsulation systems for bioactive molecules.     

The impact of high voltage electrical discharge plasma on the chromatic characteristics and phenolic composition of red and white wines

The cold plasma is an emerging electrotechnology for the improvement of food safety without loss of physicochemical or sensory properties. The purpose of this study was to evaluate the effects of plasma treatments on the chromatic characteristics and phenolic composition of red and white wines. The red wine Cabernet Sauvignon and white wine Graševina were treated with high voltage electrical discharge plasma considering the variations in frequency (60, 90 and 120 Hz) and processing time (3, 5 and 10 min). Total phenolics, total anthocyanins, total tannins and chromatic characteristics were analyzed by spectrophotometry while free anthocyanins, phenolic acids and flavan-3-ols by the HPLC-UV/Vis. Obtained results illustrated that plasma treatments have influenced the stability of phenolic compounds in wines without major changes in color parameters. Also, among two different processing parameters, the duration time was the most significant factor inducing changes on wines.Industrial relevanceHigh voltage electrical discharge plasma has been shown to affect the stability of wine phenols without any significant change in the color. An increase in the concentration of certain phenolic compounds in white wine suggest that this technique could be used in the wine industry as an alternative technique for enhancing the oxidative stability of wine and consequently the wine quality during the aging process.     

Determination of phenolic composition and antioxidant capacity of native red wines by high performance liquid chromatography and spectrophotometric methods

A reversed-phase high performance chromatographic method for simultaneous determination of 14 phenolic compounds in native red wines was developed in this study. The identified compounds contained gallic acid, (+)-catechin, 3,4-dihydroxybenzoic acid, chlorogenic acid, (?)-epicatechin, 4-hydroxybenzoic acid, syringic acid, caffeic acid, p-coumaric acid, rutin, resveratrol, myricetin, quercetin and kaempferol. The method includes liquid–liquid extraction of acidic pH with ethylacetate. The analysis used a Zorbax Eclipse XDB-C18 column (5 μm, 4.6 mm × 250 mm). The chromatographic separation of these compounds performed in a single run by using the mobile phase gradient elution of methanol water mixture (% 0.2 formic acid) at room temperature, with flow rate at 1 mL/min. Detection was carried out by UV–vis and fluorescence detector. Each analysis required an equilibration period of 10 min and a run time of 14 min for completion. The optimized chromatographic method was carefully validated for precision and accuracy. Our findings indicated that the developed HPLC method was precise, accurate, specific and sensitive for simultaneous determination of phenolic compounds. Consequently, the described method was applied to the analysis of six wines from Malatya and Elaz??. Gallic acid was dominant phenolic acid in red wines. (+)-catechin, (?)-epicatechin and p-coumaric acid were the next most abundant phenolics. The highest level of trans-resveratrol among the red wines was found Buzba?? (Bogazkere–Öküzgözü). The red wines were analyzed for total polyphenol content (TP) by Folin–Ciocalteu (FC) method, using gallic acid as standard. Antioxidant activities (AA) of the red wines were measured using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. There was a very high correlation between AA and TP in all of the wines tested.     

Chemical and sensory characterization of oxidative behavior in different wines

In wine making, the redox phenomena are responsible for profound changes in the wine’s chemical composition. Twenty wines set has been selected trying to cover a wide range of behaviors against to oxidation–reduction phenomenon. Free SO₂ level was adjusted to the maximum level found to avoid its influence from the wine oxidative trend. Samples of this set of wines were submitted to extreme conditions during 1 month. Samples were taken in different days for sensorial and chemical analysis. It is proved that red wines oxidation velocity is much higher than white wines. Aldehydes were quantified by gas chromatography–negative ion mass spectrometry (GC–NCI–MS) using a previous derivatization procedure. In conclusion, it can be said that the speed at which the sensory characteristics of wine changes are loosely related to the production of relevant odor active aldehydes, particularly to levels of methional and phenylacetaldehyde. In general, red wines produce those aldehydes during oxidation at a much higher speed than white wines, which is in agreement with the observed changes in sensory properties. However, it was not possible to find good correlations between sensory changes and aldehyde production within the red or white subsets.     

Effects of high hydrostatic pressure on physicochemical properties,enzymes activity,and antioxidant capacities of anthocyanins extracts of wild Lonicera caerulea berry

Wild Lonicera caerulea berries were subjected to five different high hydrostatic pressure (HHP) treatments (which resemble the conditions of active component extraction and commercial sterilization). The content of anthocyanins and total phenolics increased by 6.84% and 14.35% (p < 0.05), respectively after treatment at 200 MPa for 5 and 10 min. As HHP increased, a higher loss of active component was observed. The total phenolic contents did not differ significantly between the control and the 400 MPa/20 min treated group (p > 0.05); HHP processing demonstrated better sterilization effect but severely destroyed enzymes. Polyphenol oxidase (PPO) and peroxidase (POD) activity were activated at lower HHP, such as 200 MPa, and decreased at 400–600 MPa. Superoxide dismutase (SOD) maintained good stability under HHP processing. The antioxidant capacities of anthocyanins extracts of wild L. caerulea berry were evaluated by 3 different methods (DPPH assay, oxygen radical absorbance capacity assay, and cellular antioxidant activity assay).Industrial RelevanceFactors such as color, luster, and nutrition often affect consumer choice in food. However, the color and nutrition of foods tend to be destroyed during processing and storage. The demand for healthier and more nutritious food while retaining the color and flavor after processing highlights the need to develop novel and gentler technologies for fruit processing. Recently, high hydrostatic pressure (HHP) technologies have been used in different branches of the food industry. In the present study, the content of active component in blue honeysuckle fruit pulps such as anthocyanins and polyphenols showed tendency to increase and then decrease with increasing pressure at room temperature. Five different HHP treatment groups (resembling the conditions of active component extraction conditions and commercial sterilization) were compared to the control (fresh fruit) and heat-treated group to determine the effects of HHP processing on L. caerulea berry pulps. The aim of this study was to investigate the changes in active component particularly the content and composition of anthocyanins under different high-pressure treatment at room temperature; the color and physicochemical indexes were also analyzed at the same conditions. Low HHP for a long period of time (400 MPa/20 min) demonstrated better results than that with high HHP for a short time (600 MPa/10 min), as indicated by the higher contents of anthocyanins and phenols and stronger antioxidant capacities. Therefore, Low HHP conditions can be used as an auxiliary means of active component extraction. The conditions of HHP processing at low HHP for a long period of time (400 MPa/20 min) can be altered to retain active components during food processing.     

Inhibition of the decrease of volatile esters and terpenes during storage of a white wine and a model wine medium by caffeic acid and gallic acid

Caffeic acid and gallic acid were tested as inhibitors of the decrease of volatile acetate esters, ethyl esters and terpenes during storage of a white wine and a model wine medium. Wine and model wine samples were analysed by SPME along with GC–MS. At t = 0, no effect on the concentration of any volatile was observed as a result of adding each phenolic acid in any of wine or model wine samples. Many esters, such as isoamyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, and linalool decreased during storage of Debina-white wine for up to 20 months. Caffeic acid and gallic acid at 60 mg/L inhibited the decrease of these volatiles. Isoamyl acetate, ethyl hexanoate and linalool decreased during storage of the model wine medium containing 0, 20 or 40 mg/L SO₂. Caffeic acid and gallic acid inhibited the decrease of three volatiles; SO₂ inhibited the decrease of isoamyl acetate and ethyl hexanoate. In some cases, SO₂ increased the inhibitory action of two phenolic acids. The inhibitory action of caffeic acid and gallic acid was dose dependent in the range 0–60 mg/L. Caffeic acid was active at 7.5 mg/L while gallic acid at 15 mg/L.Present results indicate that caffeic acid and gallic acid may be taken into account as potent inhibitors of the disappearance of aromatic volatile esters and terpenes in wines at concentrations similar to those existing in wines.     

Characteristics and in vitro anti-inflammatory activities of protein extracts from pre-germinated black soybean [Glycine max (L.)] treated with high hydrostatic pressure

We investigated the influence of high hydrostatic pressure (HHP) and pre-germination on black soybean protein and peptide characteristics. Black soybean was germinated (2 or 4 d) and subjected to HHP (0.1–150 MPa; 24 h), followed by preparation of extracts and testing for anti-inflammatory activity. The highest soluble protein content (815.85 mg/g) was in soybeans subjected to HHP (100 MPa) after germination (4 d). Germination and HHP caused the degradation of high molecular weight proteins; we detected the highest content of < 3 and < 10 kDa peptides (60.46 and 88.47 mg) and free amino acids (65.70 mg) in extracts from pre-germinated soybeans that received HHP (150 MPa). Pre-germinated (4 d) soybean extracts treated with HHP (150 MPa) significantly inhibited LPS-induced expression of inflammatory markers, nitric oxide (25.01%), TNF-α (76.78%), IL-1β (58.99%), and IL-6 (84.48%) by RAW 264.7 macrophages. These results suggest that peptides derived from black soybeans subjected to HHP and pre-germination may mediate anti-inflammatory activity.     

The effects of high hydrostatic pressure at subzero temperature on the quality of ready-to-eat cured beef carpaccio

We compared the application of high hydrostatic pressure (HHP) on unfrozen carpaccio (HHP at 20 °C) and on previously-frozen carpaccio (HHP at − 30 °C). HHP at 20 °C changed the color. The pressure increase from 400 to 650 MPa and the time increment from 1 to 5 min at 400 MPa increased L* and b*. a* decreased only with 650 MPa for 5 min at 20 °C. The prior freezing of the carpaccio and the HHP at − 30 °C minimized the effect of the HHP on the color and did not change the shear force, but increased expressible moisture as compared to the untreated carpaccio. HHP at 20 °C was more effective in reducing the counts of microorganisms (aerobic total count at 30 °C, Enterobacteriaceae, psychrotrophs viable at 6.5 °C and lactic acid bacteria) than HHP at − 30 º C. With HHP at 20 °C, we observed a significant effect of pressure and time on the reduction of the counts.     

Effects of high hydrostatic pressure on rheological and thermal properties of chickpea (Cicer arietinum L.) flour slurry and heat-induced paste

Thermorheological changes in high hydrostatic pressure (HHP)-treated chickpea flour (CF) slurries were studied as a function of pressure level (0.1, 150, 300, 400, and 600 MPa) and slurry concentration (1:5, 1:4, 1:3, and 1:2 flour-to-water ratios). HHP-treated slurries were subsequently analyzed for changes in properties produced by heating, under both isothermal and non-isothermal processes. Elasticity (G′) of pressurized slurry increased with pressure applied and concentration. Conversely, heat-induced CF paste gradually transformed from solid-like behavior to liquid-like behavior as a function of moisture content and pressure level. The G′ and enthalpy of the CF paste decreased with increasing pressure level in proportion with the extent of HHP-induced starch gelatinization. At 25 °C and 15 min, HHP treatment at 450 and 600 MPa was sufficient to complete gelatinization of CF slurry at the lowest concentration (1:5), while more concentrated slurries would require higher pressures and temperature during treatment or longer holding times.Industrial relevanceDemand for chickpea gel has increased considerably in the health and food industries because of its many beneficial effects. However, its use is affected by its very difficult handling. Judicious application of high hydrostatic pressure (HHP) at appropriate levels, adopted as a pre-processing instrument in combination with heating processes, is presented as an innovative technology to produce a remarkable decrease in thermo-hardening of heat-induced chickpea flour paste, permitting the development of new chickpea-based products with desirable handling properties and sensory attributes.     

Adaptability of some French red grape varieties cultivated at two different Portuguese terroirs: Comparative analysis with two Portuguese red grape varieties using physicochemical and phenolic parameters

In the last year's, several French grape varieties have been introduced in different world wine regions, increasing their representation in the world. Consequently, it is important to analyze the adaptability of several red grape varieties from French origin to the other specific ‘terroirs’ and compare their characteristics with native grape varieties. Thus, the aim of this study was to evaluate the physicochemical and phenolic composition of five French red grape varieties and two Portuguese red grape varieties grown at two different Portuguese wine regions. In general, French (except ‘Alicante Bouschet’ grape variety) and Portuguese red grape varieties collected in the vineyard located in ‘Dão’ wine region had higher positive physicochemical characteristics, especially for estimated alcohol degree and titratable acidity. Regarding the phenolic composition, French grape varieties showed significantly higher values of total phenols and flavonoid compounds, especially for the grape samples collected in the vineyard located in ‘Dão’ region. Thus, for example ‘Alicante Bouschet’ grape variety showed the highest values for total phenolic (global average value from 0.636 to 0.894 mg g^− 1 of berry) and flavonoid compounds (global average value from 0.584 to 0.834 mg g^− 1 of berry). However, for total anthocyanins it was clear that the two Portuguese grape varieties studied (‘Touriga Nacional’ and ‘Tinta Roriz’) showed significantly highest values independently of the wine region considered (global average value ranged from 0.603 to 0.785 mg g^− 1 of berry). Similar tendency was also confirmed by significantly highest global average values for the sum of the glycosylated derivatives, where the values ranged from 0.389 to 0.539 mg g^− 1 of berry, for the two Portuguese grape varieties considered.