Grape Stem Extracts Research Articles

Green Extraction Strategy Using Bio-Based Aqueous Biphasic Systems for Polyphenol Valorization from Grape By-Product.

Polyphenols are natural compounds with enhanced antioxidant properties. They are present in relatively high concentrations in fruit/vegetable by-products. Therefore, there is a need for the development of efficient and cost-effective methods for the separation and purification of these valuable compounds. Traditional extraction with organic solvents needs to be switched to novel methods that are more efficient, with reduced extraction times and low consumption of organic solvents. Aiming at developing sustainable processes for the separation and purification of phenolic compounds, we used three model compounds, namely resveratrol, quercetin, and gallic acid, to investigate ionic liquid-based aqueous biphasic systems (IL-ABSs) formed by cholinium-based IL in combination with polypropylene glycol with a molecular mass of 400 g/mol (PPG400). The ABS composition in the two-phase region was selected according to a previously determined phase diagram. Extraction studies indicated the preferential partition of resveratrol and quercetin toward the hydrophobic PPG-rich phase that is mainly dominated by its hydrophobic nature and the strong salting-out effect of ILs. On the other hand, due to its considerably hydrophilic nature, gallic acid preferentially migrates toward the IL phase. The achieved results from grape stem extract demonstrated high extraction efficiencies of cholinium dihydrogen phosphate (~99% for resveratrol for the PPG phase and 78% for gallic acid for the IL phase), with considerable selectivity, demonstrating promising outcomes for potential applications.

Biologically valuable components of grape stems

The current problem of recycling winemaking waste is largely determined by the lack of technological cycles and waste-free technology schemes that can ensure the rational use of natural resources, including grape stems, when creating functionally new composite compositions designed to support human immunity and health. The most effective way to recover raw materials from grape stems is to produce extracts from them. As part of the study, the qualitative and quantitative phenolic composition of grape stem extracts was established. The methodology and technological regimes for the preparation of grape stems, as well as the ranges for varying the content of biologically valuable components in extracts from the stems, have been established. The use of the proposed scheme for obtaining extracts will allow us to separate the process of extracting the components of grape stems from infusion and will allow us to develop a number of technological advantages: targeted regulation of the quality of grape processing products, more complete use of raw materials, and reduction of losses of basic and auxiliary materials.

Revealing the Beauty Potential of Grape Stems: Harnessing Phenolic Compounds for Cosmetics.

Grape stems have emerged as a promising natural ingredient in the cosmetics industry due to their abundance of phenolic compounds, known for their antioxidant and anti-inflammatory properties. These compounds have shown great potential in promoting skin health, fighting signs of aging, and shielding against environmental stressors. With high concentrations of resveratrol, flavonoids, and tannins, grape stems have garnered attention from cosmetic scientists. Research has indicated that phenolic compounds extracted from grape stems possess potent antioxidant abilities, effectively combating free radicals that accelerate aging. Moreover, these compounds have demonstrated the capacity to shield the skin from UV damage, boost collagen production, and enhance skin elasticity. Cosmetic formulations incorporating grape stem extracts have displayed promising results in addressing various skin concerns, including reducing wrinkles, fine lines, and age spots, leading to a more youthful appearance. Additionally, grape stem extracts have exhibited anti-inflammatory properties, soothing irritated skin and diminishing redness. Exploring the potential of grape stem phenolic compounds for cosmetics paves the way for sustainable and natural beauty products. By harnessing the beauty benefits of grape stems, the cosmetics industry can provide effective and eco-friendly solutions for consumers seeking natural alternatives. Ongoing research holds the promise of innovative grape stem-based formulations that could revolutionize the cosmetics market, fully unlocking the potential of these extraordinary botanical treasures.

Implication of the Polymeric Phenolic Fraction and Matrix Effect on the Antioxidant Activity, Bioaccessibility, and Bioavailability of Grape Stem Extracts

The bioaccessibility and bioavailability of phenolics compounds of two grape stem extracts with different composition were studied. High polymeric extract (HPE) presented a higher content of total phenolics (TPC), procyanidins, hemicelluloses, proteins, and ashes, whereas low procyanidin extract (LPE) showed a higher fat, soluble sugars, and individual phenolic compounds content. Corresponding to its higher total phenolics content, HPE possesses a higher antioxidant activity (TEAC value). The digestion process reduced the antioxidant activity of the HPE up to 69%, due to the decrease of TPC (75%) with a significant loss of polymeric compounds. LPE antioxidant activity was stable, and TPC decreased by only 13% during the digestion process. Moreover, a higher antioxidant phenolic compounds bioavailability was shown in LPE in contrast to HPE. This behaviour was ascribed mainly to the negative interaction of polymeric fractions and the positive interaction of lipids with phenolic compounds. Therefore, this study highlights the convenience of carrying out previous studies to identify the better extraction conditions of individual bioavailable phenolic compounds with antioxidant activity, along with those constituents that could increase their bioaccessibility and bioavailability, such as lipids, although the role played by other components, such as hemicelluloses, cannot be ruled out.

Redox Biomarkers Assessment after Oral Administration of Wine Extract and Grape Stem Extract in Rats and Mice

Wine and by-products of the winemaking process, such as grape stems, are rich in bioactive polyphenolic compounds that might be beneficial for animal and human health. In recent years, the administration of dietary polyphenols with strong antioxidant and cytoprotective properties has constituted an emerging line of research interest toward disease prevention. However, in scientific literature, only a limited number of studies have investigated the safety and the toxicological risks of polyphenolic compounds in vivo. Based on the above, the purpose of the present study was two-fold: first, to examine the effects of oral administration of a grape stem extract, derived from the Greek red wine Mavrodaphne, on mice redox biomarkers; and second, to investigate the biological effects of oral administration of a wine extract, derived from the emblematic Greek red wine Xinomavro, on rats. Toward this purpose, body weight, growth rate, hematological, biochemical, and histopathological parameters, as well as a panel of redox biomarkers, were examined. According to our results, the administration of Mavrodaphne grape stem extract in mice induced alterations in redox homeostasis, preventing mice from the adverse effects of lipid peroxidation. Contrariwise, the administration of Xinomavro wine extract induced both beneficial and harmful outcomes on rat redox status determined by the examined tissue. Collectively, our study reports that the Mavrodaphne grape stem extract, a serious pollutant when disposed in environmental matrices, is an important source of bioactive polyphenolic compounds that could protect from oxidative damage and improve animal and human health. Finally, the Xinomavro wine extract exerts tissue-specific changes in redox balance, which are indicative of the complexity that characterizes the biological systems.

Evaluation of grape stems and grape stem extracts for sulfur dioxide replacement during grape wine production

Sulfur dioxide (SO2), the main preservative in wine, may affect the sensory properties of the wines, as well as cause allergic reactions and headaches in sensitive people. The aim of this work was to evaluate the replacement of SO2 in Tempranillo wines with Mazuelo grape stem products. Five Tempranillo red wines were elaborated: positive control (60 mg/L SO2); negative control with no preservatives; Mazuelo extract (200 mg/L); Mazuelo extract combined with SO2 (100 mg/L + 20 mg/L); and Mazuelo stem (400 mg/L). The oenological parameters, antioxidant capacity, total phenolic (TP), total flavonoids (TF) and total anthocyanins (TA) contents were determined. Additionally, individual phenols were analyzed by HPLC-DAD-FLD. The spectrophotometric analyses showed that the wines had similar antioxidant capacities and concentrations of TP and TF. However, TA was more affected by the lack of SO2 as anthocyanins presented higher concentrations in positive control samples. The concentrations of individual phenols followed a similar path in all samples. Wines containing sulfites were more similar than the other treatments. However, these similarities were not reflected on the sensory analysis performed, as triangle test did not show differences between the wine with extract addition and the positive control wine. Therefore, Mazuelo stem extract could be a possible strategy for SO2 replacement. Nevertheless, further studies are necessary to confirm the potential of grape stem extracts as wine preservative.

Redefining the Use of Vinification Waste By-Products in Broiler Diets

In this study, the use of vinification by-products in broiler diets, as a sustainable and promising way of exploiting them, was examined. In particular, the potential use of ground grape pomace (GGP), wine lees extract (WYC) and grape stem extract (PE) in broiler diets was examined. Growth performance parameters, the weight of selected internal organs, meat quality traits, fatty acid profiles of breast meat and selected haematological parameters were determined. Two hundred and forty one-day-old broilers were assigned to four treatments with four replicate pens of fifteen broilers. There was one control treatment (CON), fed a basal diet, and the GGP, WYC and PE treatments, fed a basal diet supplemented with 25 g/kg GGP, 2 g/kg WYC and 1 g starch including 100 mg pure stem extract/kg PE, respectively. The duration of the experiment was 42 days. The average body weight gain during the starter, grower and finisher stages did not differ among treatments. Similarly, the feed intake, FCR and carcass yield did not show a significant difference. The weight of the internal organs was also similar among treatments. Some positive differences were observed in colour traits of meat and in haematological parameters. In the GGP group, saturated (SFAs) and unsaturated fatty acids (USFAs) were lower and higher, respectively, compared to the CON, WYC and PE groups. Vinification by-products seem to be a promising feed additive in broiler diets providing a sustainable approach to grape waste management without affecting broiler performance.

Combination of Pulsed Electric Field and Ultrasound in the Extraction of Polyphenols and Volatile Compounds from Grape Stems

Increasing the yield of extraction of bioactive compounds from plants is of high importance. Grape stems are widely discarded during the wine-making process, despite their high content in many valuable compounds. The aim of this work was to examine whether the use of pulsed electric field (PEF) treatment of the stems could increase the yield of polyphenol and volatile compounds in the extracts. For this reason, a relatively low-energy consuming PEF process was employed (low-electric field strength, 1 kV/cm) for a short time (30 min) at the grape stems. In addition, the effect of different solvents during this pretreatment step was examined. With the use of Folin–Ciocalteu assay, the extracts were compared with the respective control samples (not pretreated with PEF). Moreover, extracts were prepared to assess whether changes occur to the volatile profile of the extracts. The results were conclusive that not only PEF can increase the yield of polyphenols (up to 35% increase recorded), but also that the solvent used during PEF pretreatment can affect the process. Furthermore, a 234% increase in the total content of volatile compounds was recorded, when PEF was used as a pretreatment step. Therefore, the combination of PEF and ultrasound-assisted extraction is highly promising to obtain grape stem extracts with a higher content of bioactive compounds.

Study on the Chemical Composition and the Biological Activities of Vitis vinifera Stem Extracts.

Vitis vinifera (V. vinifera) is a herbaceous plant, cultivated worldwide and known for its biological benefits. The aim of this study is the investigation of the chemical composition as well as the determination of the biological potential of different grape stem extracts obtained by maceration and accelerated solvent extraction (ASE). The HPLC analysis of the tested extracts led to the identification of 28 compounds of which 17 were identified for the first time in grape plants, in addition to seven revealed in the stem part for the first time. Twenty-nine volatile molecules have been detected by GC-MS in the grape stem part; among them seven were identified for the first time in the grape plant. For the biological analysis, the ethyl acetate extract (EtOAc) obtained by maceration showed a significant potential regarding antioxidant activity (IC50 = 42.5 µg/mL), anti-Alzheimer (IC50 = 14.1 µg/mL), antidiabetic (IC50 = 13.4 µg/mL), cytotoxic with HCT-116 (IC50 = 12.5 µg/mL), and anti-inflammatory (IC50 = 26.6 µg/mL) activities, as well as showing the highest polyphenol content (207.9 mg GAE/g DW).

Biological effects of grape stem extracts on human cancer cell lines

Grapes are rich in polyphenolic compounds, which are known for their beneficial effects on human health. Grape stems are byproducts of the winemaking procedure. They exert antioxidant effects; however, they can also become pollutants when discarded without control into the environment due to their high organic content. The main aim of the present study was to examine the potential prooxidant/anticancer effects of grape stem extracts, promoting the rationale of the scientific exploitation of such compounds. Therefore, three grape stem extracts derived from the native Greek vine varieties, Mavrodaphne, Muscat and Rhoditis were examined for their ability to alter the redox status [i.e., endogenous levels of reduced glutathione and reactive oxygen species (ROS)] of HeLa and HepG2 human cancer cell lines. The results revealed that the extracts from Muscat and Rhoditis exerted prooxidant effects on the tested cell lines, whereas the extract of Mavrodaphne did not exert any such effects. The fact that the extracts functioned as prooxidants appears to be detrimental for the cancer cells, since they are more susceptible to high concentrations of ROS, contrary to healthy cells that possess more robust antioxidant defense mechanisms. On the whole, as demonstrated in the present study, it appears that the Muscat and Rhoditis extracts may prove to be promising agents against cancer cells in the specific <em>in vitro</em> model. However, further studies are required to confirm these findings, in <em>in vivo</em> settings.

Impact of the Phenolic Matrix in Terms of Phenolic Polymerization on the Bioaccessibility and Bioavailability of the Low Molecular Phenolic Compounds, and the Antioxidant Activity, of Pressurized Liquid Grape Stem Extracts

Impact of the Phenolic Matrix in Terms of Phenolic Polymerization on the Bioaccessibility and Bioavailability of the Low Molecular Phenolic Compounds, and the Antioxidant Activity, of Pressurized Liquid Grape Stem Extracts

Immune-Related Gene Expression Profiling of Broiler Chickens Fed Diets Supplemented with Vinification Byproducts: A Valorization Approach II.

Simple SummaryThe valorization of grape byproducts appears to be a sustainable bioeconomic strategy that could promote the substitution of synthetic with natural antioxidant compounds in the food and feed industry. The nutritional physiology of broiler chickens requires special attention to the interactions between nutrients and antioxidant mechanisms since the stressor signals of factory farming could impair the immune status, resulting in detrimental effects on broilers’ performance. The objective of this study was to assess the inclusion of grape byproducts (grape pomace, wine lees, and stem extract) on the transcriptional profiling of genes regulating the immune system in the liver, bursa of Fabricius, and spleen. The dietary supplementation of grape byproducts rich in polyphenolic compounds decreased the mRNA levels of the predominant pro-inflammatory receptor in the liver, while in the spleen, the stem extract diet upregulated the aforementioned receptor. Upregulation of interleukin 8 was observed in the bursa of Fabricius and spleen of the stems extract-fed broilers. Although grape byproducts depicting a sustainable source of bioactive compounds with vast antioxidant potential, there were unveiled preliminary insights for immune stimulation at the transcriptional level.The valorization of vinification byproducts portrays a promising bioprocess for the enrichment of animals’ diet with bioactive compounds, such as polyphenols, which could regulate the immune response. Therefore, the impact of dietary grounded grape pomace (GGP), wine lees extract (WYC), and grape stem extract (PE) on the relative transcript level of immune related genes of broiler chickens were examined. Two hundred forty, one-day-old as hatched (male/female) chicks (Ross 308) were allocated to four dietary groups, with four replicate pens each with 15 birds. Birds were fed either a basal diet (CON) or the basal diet supplemented with 2.5% GGP, or 0.2% WYC, or 0.1% PE for 42 d. The relative expression of immune-related genes was investigated using a real-time PCR platform. The mRNA levels of Toll-like Receptor 4 (TLR4) were downregulated (p = 0.039) in the liver of broilers fed the GGP-containing diet compared to the CON, while in the spleen of PE-fed broilers, TLR4 was significantly upregulated (p = 0.043). The mRNA levels of interleukin 8 (IL8) tended to upregulate (p = 0.099) in the bursa of Fabricius and were significantly increased (p = 0.036) in the spleen of broilers fed the PE diet. Vinification byproducts depict a promising sustainable source of polyphenols for the poultry feed industry, but more research is needed under field conditions.

Phenolic Composition of Grape Stems from Different Spanish Varieties and Vintages.

Grape stems are a by-product from the wine industry that has been underused to date despite having great potential for the agro-food and cosmetic industries. The aim of the present work was to characterize grape stem extracts obtained from different grape varieties from two vintages (2016 and 2018). Both spectrophotometric and chromatographic methods were used for sample characterization. The results showed that there exist significant differences in antioxidant activity, total phenolic content (TPC) and total flavonoid content (TF) among grape stems from different varieties in each vintage and from different vintage for the same variety. Catechin was the most abundant phenolic compound in all extracts from both vintages. In general, Mazuelo presented higher concentration values of the different phenolic compounds than Garnacha and Tempranillo. It was observed than extreme temperatures and accumulated precipitations, which were higher in the 2016 vintage, had an impact on the polyphenol synthesis. Therefore, grape stems from the 2018 vintage presented higher TPC and TF values than their counterparts from the 2016 vintage. In addition, the statistical analysis revealed that the influence of environmental factor such as light, temperature and precipitations have different impact on the synthesis of polyphenols depending on the family of the specific compound.

Antioxidant Status of Broiler Chickens Fed Diets Supplemented with Vinification By-Products: A Valorization Approach.

Vinification by-products display great potential for utilization as feed additives rich in antioxidant compounds. Thus, the effect of dietary ground grape pomace (GGP), wine lees extract rich in yeast cell walls (WYC), and grape stem extracts (PE) on the relative expression of several genes involved in liver oxidative mechanisms and the oxidative status of the blood and breast muscle of broiler chickens was investigated. In total, 240 one-day-old as hatched chicks (Ross 308) were assigned to four treatments, with four replicate pens and 15 birds in each pen. Birds were fed either a basal diet (CON) or a basal diet supplemented with 25 g/kg GGP, or 2 g/kg WYC, or 1 g starch including 100 mg pure stem extract/kg (PE) for 42 days. The polyphenolic content of vinification by-products was determined using an LC-MS/MS library indicating as prevailing compounds procyanidin B1 and B2, gallic acid, caftaric acid, (+)-catechin, quercetin, and trans-resveratrol. Body weight and feed consumption were not significantly affected. The relative transcript level of GPX1 and SOD1 tended to increase in the liver of WYC-fed broilers, while NOX2 tended to decrease in the PE group. SOD activity in blood plasma was significantly increased in WYC and PE compared to the CON group. The total antioxidant capacity measured with FRAP assay showed significantly higher values in the breast muscle of PE-fed broilers, while the malondialdehyde concentration was significantly decreased in both WYC- and PE-fed broilers compared to the CON group. The exploitation of vinification by-products as feed additives appears to be a promising strategy to improve waste valorization and supply animals with bioactive molecules capable of improving animals’ oxidative status and products’ oxidative stability.

Effect of winery by-product extracts on oxidative stability, volatile organic compounds and aroma profile of cooked pork model systems during chilled storage

Grape stem and vine-shoot extracts have been studied in cooked pork model system as alternative preservatives to prevent oxidation reactions. After cooking, samples were stored in refrigeration and analyzed at 0, 10 and 20 d. Winery extracts addition (3 g/100 g) preserved better redness loss and reduced lipid and protein oxidation during chilled storage, being more effective than the traditional additive sodium ascorbate. A significant increase of total phenolics content and catechins, and the subsequent greater antioxidant capacity, were observed in samples added with winery extracts, being particularly noticeable in those treated with vine-shoot extract. Furthermore, volatile organic compounds (VOCs) concentration derived from lipid oxidation during chilled storage were lessen inhibited thanks to the extracts addition. Nonanal, some unsaturated aldehydes and octanoic acid showed high odor activity values (OAVs) in control samples after storage, evoking rancid odors. In this sense, winery by-products samples did not exhibit these flavors whereas distinguished pleasant sensorial features described as “herbaceous” or “woody” were found.

Grape Stem Extracts with Potential Anticancer and Antioxidant Properties.

The application of plant extracts for therapeutic purposes has been used in traditional medicine because plants contain bioactive compounds with beneficial properties for health. Currently, the use of these compounds that are rich in polyphenols for the treatment and prevention of diseases such as cancer, diabetes, and cardiovascular diseases, many of them related to oxidative stress, is gaining certain relevance. Polyphenols have been shown to have antimutagenic, antioxidant, and anti-inflammatory properties. Therefore, the objective of the present work was to study the potential effect of grape stem extracts (GSE), rich in phenolic compounds, in the treatment of cancer, as well as their role in the prevention of this disease associated with its antioxidant power. For that purpose, three cancer lines (Caco-2, MCF-7, and MDA-MB-231) were used, and the results showed that grape stem extracts were capable of showing an antiproliferative effect in these cells through apoptosis cell death associated with a modification of the mitochondrial potential and reactive oxygen species (ROS) levels. Additionally, grape stem extracts showed an antioxidant effect on differentiated intestinal cells that could protect the intestine from diseases related to oxidative stress. Therefore, grape extracts contain bioactive principles with important biological properties and could be used as bio-functional food ingredients to prevent diseases or even to improve certain aspects of human health.

Encapsulated Bioactive Ingredients of grape by‐products applicate in fresh‐cut fruit and juices diminished the ochratoxins

Various fruits are involved in food models, including fresh-cut fruit, fruit salad, and juices. Toxigenic fungi in horticulture have attracted interest in order to the food safety requirements and their illnesses relation. This study aimed to apply grape by-products (Gbps) that contain bioactive compounds to reduce mycotoxin and limit toxigenic fungal-activity in fresh-cut fruit and juice. The Gbps were collected and extracted using ultra-sonication. Phenolic, flavonoids, antioxidants, and antifungal activities of extracts were evaluated. Grape stem and leaf extracts were micro capsulated to apply as bio-preservatives in food. The stems extract showed higher contents of p-coumaric and Ferulic acids. Leaves extract showed higher contents of epicatechin, quercetin, while rutin was high in both extracts. Stems extract showed high phenolic contents and more antifungal activity than leaves extract. Microcapsules of stem extract provided a greater ochratoxin reduction than that achieved by leaves microcapsules when they applied to juices or fruit salads. Practical Applications This work aims to extend shelf life and increase the safety of some horticultural products that relatively consumed quickly, such as fresh-cut fruits, fruit salad, and juices. Those products traded in supermarkets as slides or kept deep in solutions. Results showed that; utilization of grape by-product extracts as bioactive capsules; formed a film on the product; had potency in the reduction of contamination and mycotoxin possibility, in horticultural products. This application will increase horticultural time availability in markets and facilitate their handling without the risk of contamination increases. In addition, it assists reducing mycotoxins if it was available in raw materials.

Reducing SO2 Doses in Red Wines by Using Grape Stem Extracts as Antioxidants.

SO2 is a very important wine preservative. However, there are several drawbacks associated with the use of SO2 in wine. The aim of this work is to evaluate the effect of the partial substitution of SO2 in the Tempranillo wine by a Mazuelo grape stem extract and by a commercial vine wood extract (Vinetan®). The results were compared with a control sample (with no addition of any extract). After 12 months of storage in a bottle, total anthocyanin content, together with total polyphenol and flavonoid content were slightly higher for control wines than for those treated with extracts. These differences were of little relevance, as no differences in antioxidant activity were found between any of the wines at the end of the study. The sensory analysis revealed that the use of both extracts as partial substitutes of SO2 could lead to wines with good organoleptic properties, similar or even better to the control ones.

Study of white frangipani flower and bitter grape stem ethanol extract combination on antibacterial and antioxidant activities

Frangipani flower (Plumeria acuminata) and bitter grape (Tinospora crispa L. Miers) stem extract alone shows antimicrobial and antioxidant activities. However, there is a limited report about the actions from the combination of both extracts. Combinations of ethanol extract of white frangipani flower (EFF) and ethanol extract of the bitter grape stem (EBS), each of 0, 1, 2, and 3% were tested for inhibition against Staphylococcus aureus growth and DPPH (1,1-diphenyl,2-picrylhydrazyl) free radicals. A yield of 3.17 and 2.62 g of EFF and EBS, respectively, were resulted from 100 g of dried powdered of the white frangipani flower and bitter grape stem using 200 mL of absolute ethanol. The antimicrobial test was assayed using a 10% stock solution of extract diluted in water. The combination of EFF and EBS showed a synergistic effect on antimicrobial activity, but it proved an antagonistic effect on antioxidant activity. The combination of EFF 3% and EBS 3% showed the highest inhibition index on the S. aureus growth , i.e. 2.02±0.06, which is higher than the inhibition index of Amoxycillin 2%, i.e. 1.85±0.09. The highest antioxidant activity showed by 1% EFF alone (57.5 ± 0.60%), while the lowest was from the combination of EFF 1% and EBS 3% (23.4±0.30%).

Stability of Phenolic Compounds in Grape Stem Extracts.

Grape stem is rich in phenolic compounds, especially stilbenes. These antioxidants can be degraded during the storage of grape stem extracts for long periods of time. The aim of this work was to analyze the stability of Mazuelo stem extracts during storage at 25 and 40 °C, in two different light conditions (amber and transparent vials). The stability of the antioxidants was studied after 2, 4 and 6 months of conservation. Gallic acid and the quercetin derivative concentration were stable throughout the storage period. In contrast, catechin disappeared from all the extracts in just two months of storage. Anthocyanins were significantly affected by temperature, and light enhanced their degradation when the extracts were kept at 40 °C. Resveratrol and viniferin showed a similar behavior. Their concentration decreased from the beginning of storage, and in both cases, they were significantly affected by both temperature and light.