Wine Constituents Research Articles

Resveratrol transformation in red wine after heat treatment

Resveratrol is a well-known wine constituent. Its concentration can vary according to the cultivar choice and the winemaking process. Due to its phenolic structure, resveratrol could be transformed under high temperature or oxidative conditions, leading to the formation of various derivatives including oligomers. Hence, the goal of this study is to investigate the presence of these derivatives in wine. In the first stage, hemisynthesis of oligomeric stilbenes was achieved from resveratrol in ethanol by oxidative coupling using metals. Four de novo synthetized resveratrol derivatives were identified by MS and NMR spectroscopy including two new molecules, oxistilbenin F and oxistilbenin G. In the second stage, analysis of red wine after heat treatment by LC-MS confirmed the presence of some of these compounds in wine. Finally, the anti-inflammatory effects of the compounds were evaluated by studying their ability to prevent lipopolysaccharide (LPS)-induced upregulation of nitric oxide (NO) and reactive oxygen species (ROS) production in RAW 264.7 macrophage cell line.

Wine tannins: Where are they coming from? A method to access the importance of berry part on wine tannins content

Phenolic compounds are important constituents of red wine involved in its sensory properties. Although wine tannins can come from microbial and oak sources, the main sources of polyphenol remains grape skins and seeds. In order to better understand the grape seed and skin tannins contribution to the final wine tannins content, an original approach of winemaking has been set up. Our protocol explains a simple method to determine the percentage of skin and seed tannins extracted in wine all along the winemaking. The advantages of this method are presented below:•This method allows us to describe tannins extraction kinetics in wine according to the berry part (skins and seeds).•Additionally, our protocol allows to specifically determine the percentage of tannins extraction according to the winemaking stages (alcoholic fermentation and post-fermentative maceration) and the berry part (skins and seeds).•To sum up, this method serves to enhance the comprehension of tannins extraction process in wine according to the berry part.

Bovine serum albumin-based nanoparticles containing the flavonoid rutin produced by nano spray drying

Rutin is a flavonoid compound obtained from different vegetables and fruits; specifically, it is found in the seeds of buckwheat and in fruit peels, particularly citrus. It is also an important constituent of red wine. Rutin exhibits various biological properties including antiviral, vasoprotective, anti-inflammatory, and anticarcinogenic activities. However, its antioxidant activity is the most well studied. Despite the potential for in vitro applications, rutin presents low oral bioavailability that affects its biological activities. Nanoparticles composed of polymers, protein, or lipids are of great importance in the pharmaceutical and nutraceutical areas due to their physicochemical properties, which improve the pharmacokinetics of the drug which is loaded within. This study presents the production of bovine serum albumin (BSA) nanoparticles containing rutin by nano spray drying. Nanoparticles were characterized in terms of mean particle size, size distribution, morphology, zeta potential, and drug content; as well as their antioxidant activity. The optimized spray-drying conditions produced spherical particles with a mean size of 316 nm, zeta potential of −32 mV, and encapsulation efficiency around 32%. Moreover, when antioxidant activity toward the ABTS+ radical was assayed, nanoencapsulation increased the IC50 of rutin by 2-fold. The nano spray-drying process proved to be suitable for the production of rutin-loaded BSA nanoparticles with potential antioxidant activity.

Regeneration of Magnetic Nanoparticles Used in the Removal of Pathogenesis-Related Proteins from White Wines.

Protein haze remains a serious problem for the wine industry and requires costly bentonite treatment, leading to significant wine volume loss. Recently developed magnetic separation technology that allows a fast and efficient separation of haze proteins from wine shows promise for the development of an alternative method for white wine fining. The key purpose of this study was to understand the potential of the nanoparticles to be reused in multiple fining and regeneration cycles. Bare and acrylic-acid-based plasma polymer coated magnetic nanoparticles were cleaned with water, 10% SDS/water and acetone/water solution after each adsorption cycle to investigate their restored efficiency in removing pathogenesis-related proteins from three unfined white wines. The concentrations of metals, acids and phenolics were monitored to determine changes in the concentration of these essential wine constituents. The regeneration study verified that the acrylic acid plasma-coated magnetic nanoparticles, which underwent ten successive adsorption-desorption processes, still retained close to the original removal capacity for haze proteins from wines when 10% SDS solution and water were used for surface regeneration. In addition, the concentrations of organic acids and wine phenolic content remained almost unchanged, which are important indicators for the retention of the original wine composition.

Effects of diammonia phosphate addition on the chemical constituents in lychee wine fermented with Saccharomyces cerevisiae

This study evaluated the effects of diammonia phosphate (DAP) on the non-volatile and volatile compounds of lychee wine fermented with Saccharomyces cerevisiae, when added in two different quantities (0.5 mmol/L and 1.5 mmol/L). It was found that DAP supplementation improved the utilization of ammonia and inhibited the consumption of proline and valine, which regulated the production of α-ketoglutaric, succinic and fatty acids. The addition of 0.5 mmol/L DAP improved the rate of sugar catabolism by slightly increasing yeast growth, thus inducing a higher production of glycerol than of ethanol. Additionally, more odor-active terpene derivatives (trans-β-damascenone, o-cymene, δ-guaiene) in lychee juice were retained after the fermentation added with 0.5 mmol/L DAP. However, the addition of 1.5 mmol/L DAP slowed rates of sugar metabolism and glycerol production, and significantly enhanced the production of acetic acid. Furthermore, with the exception of limonene, the higher DAP addition did not retain more terpene derivatives. These findings, therefore, suggest that a moderate addition of DAP could enhance the flavorful character of lychee wine.

A UFLC-MS/MS method for the simultaneous determination of eight bioactive constituents from red wine and dealcoholized red wine in rat plasma: Application to a comparative pharmacokinetic study.

To explore whether alcohol has an effect on the pharmacokinetic behavior of phenolic acids, the main bioactive constituents in red wine, a highly sensitive and simple ultra-fast liquid chromatography coupled with triple quadrupole mass spectrometry (UFLC-MS/MS) method was developed for simultaneous quantitation of eight phenolic acids in plasma samples. Plasma samples were extracted by liquid-liquid extraction and the chromatographic separation was achieved on a Zorbax SB-C18 column within 7.0 min. Results of the validated method revealed that all of the calibration curves displayed good linear regression (r > 0.99). The intra- and inter-day precisions of the analytes were <14.0% and accuracies ranged from -8.5 to 7.3%. The extraction recoveries of the analytes were from 71.2 to 110.2% and the matrix effects ranged from 86.2 to 105.5%. The stability of these compounds under various conditions satisfied the requirements of biological sample measurement. The method was successfully applied to a comparative pharmacokinetic study of phenolic acids in rat plasma. For gallic acid and gentisic acid, the parameters AUC0-t and AUC0-∞ increased remarkably (p < 0.05) after oral administration of red wine, which suggested that alcohol might enhance their absorption. This is the first report to compare the pharmacokinetic behavior of phenolic acids in red wine and dealcoholized red wine.

Characterization of bulk and surface properties of anion-exchange membranes in initial stages of fouling by red wine

Electrodialysis finds broader use in reagent-free pH correction and tartrate stabilization of wines. The efficiency of these processes strongly depends on longevity of employed anion-exchange membranes. We report a comprehensive study of bulk and surface properties of a homogeneous Neosepta AMX-Sb and a heterogeneous MA-41P anion-exchange membranes after its contact with a red wine for 3, 10 and 72 h. The ion-exchange capacity, conductivity, thickness, as well as surface roughness (AFM and optical microscopy), local surface and bulk pH (by color indicator), surface chemical structure (ATR FTIR), contact angle and surface charge are measured. In addition, the AMX-Sb membrane is characterized by voltammetry and pH-metry. It is found that polyphenols act an important role in membrane fouling. Initially, it is relatively small and mobile anthocyanins, which penetrate inside the membrane; then they are followed by larger and slower tannins and/or anthocyanin-tannin complexes. Polyphenols together with polysaccharides and other wine constituents form colloidal aggregates, which fill the membrane pores and are deposited by islets on the surface as a foulant layer. The appearance of this layer increases hydrophilicity of the surface while reducing its charge. The membrane conductivity decreases with increasing the duration of membrane contact with wine. However, the effect of this contact on the limiting current density, ilim, overlimiting transfer and water splitting is unexpected. In early stages of fouling, ilim of the AMX-Sb membrane increases and water splitting is found suppressed, electroconvection is essentially enhanced. The latter should be due to the isle-type structure of the foulant layer: surface electrical heterogeneity promotes electroconvection. However, the contact of the membrane with wine for several tens of hours results in formation of all-over foulant layer stimulating water splitting and reducing electroconvection.

Mechanism of resveratrol-induced relaxation of the guinea pig fundus

BackgroundResveratrol is a polyphenolic compound that can be isolated from plants and also is a constituent of red wine. Resveratrol induces relaxation of vascular smooth muscle and may prevent cardiovascular diseases. PurposeImpaired gastric accommodation plays an important role in functional dyspepsia and fundic relaxation and is a therapeutic target of functional dyspepsia. Although drugs for fundic relaxation have been developed, these types of drugs are still rare. The purpose of this study was to investigate the relaxant effects of resveratrol in the guinea pig fundus. Study DesignWe studied the relaxant effects of resveratrol in the guinea pig fundus. In addition, we investigated the mechanism of resveratrol-induced relaxation on the guinea pig fundus by using tetraethylammonium (a non-selective potassium channel blocker), apamine (a selective inhibitor of the small conductance calcium-activated potassium channel), iberiotoxin (an inhibitor of large conductance calcium-activated potassium channels), glibenclamide (an ATP-sensitive potassium channel blocker), KT 5720 (a cAMP-dependent protein kinase A inhibitor), KT 5823 (a cGMP-dependent protein kinase G inhibitor), NG-nitro-L-arginine (a competitive inhibitor of nitric oxide synthase), tetrodotoxin (a selective neuronal Na+ channel blocker), ω-conotoxin GVIA (a selective neuronal Ca2+ channel blocker) and G-15 (a G-protein coupled estrogen receptor antagonist). ResultsThe results of this study showed that resveratrol has potent and dose-dependent relaxant effects on the guinea pig fundic muscle. In addition, the results showed that resveratrol-induced relaxation of the guinea pig fundus occurs through nitric oxide and ATP-sensitive potassium channels. ConclusionThis study provides the first evidence concerning the relaxant effects of resveratrol in the guinea pig fundic muscle strips. Furthermore, resveratrol may be a potential drug to relieve gastrointestinal dyspepsia.

Combinatorial Preconditioning of Rat Brain Cultures with Subprotective Ethanol and Resveratrol Concentrations Promotes Synergistic Neuroprotection.

Preconditioning brain cultures with moderate concentrations of ethanol (EtOH) or trans-resveratrol (RES), key red wine constituents, can prevent amyloid-β (Aβ) neurotoxicity. Past studies have indicated that moderate EtOH activates synaptic N-methyl-D-aspartate receptors (NMDAR) that, in part, signal via protein kinase C (PKC) to increase protective antioxidant proteins such as peroxiredoxin-2 (Prx2). RES preconditioning also is reported to involve NMDAR and PKC. However, although moderate, the EtOH and RES concentrations used have been noticeably above circulating levels from two glasses of wine, a daily intake linked to reduced risk of cognitive decline among older social drinkers. Given their mechanistic parallels, we speculated that subprotective EtOH and RES concentrations in a combinatorial preconditioning paradigm might elicit synergistic neuroprotection. To examine this notion, rat cerebellar cultures were pretreated with 10mM EtOH (circulating concentration after ~ 2 drinks), 5μM RES, EtOH + RES combinatorially, or media alone (controls). After 3days, media were removed, and fresh media aliquots containing Aβ25-35 (25μM) were added. Assessing apoptosis 24h later with Hoescht 33342, neurodegeneration did not differ from controls in cultures separately preconditioned with 10mM EtOH or 5μM RES. However, apoptosis was prevented in combinatorially preconditioned cultures. Also, immunoblotting revealed elevated Prx2 levels due to combinatorial pretreatment that correlated with subsequent neuroprotection, whereas Prx2 was unchanged in separately pretreated cultures. Although the protective mechanisms require clarification, synergistically upregulated NMDAR-PKC-Prx2 (and other antioxidant proteins) is a reasonable component. These findings imply that EtOH + RES antioxidant synergy could be involved in neurobenefits attributed to low-moderate wine consumption.

Soluble Protein and Amino Acid Content Affects the Foam Quality of Sparkling Wine.

Proteins and amino acids are known to influence the foam characteristics of sparkling wines. However, it is unclear to what extent they promote foam formation and/or stability. This study aimed to investigate the effect of protein content and amino acid composition, measured via the bicinchoninic acid assay and high-performance liquid chromatography, respectively, on the foaming properties of 28 sparkling white wines, made by different production methods. Foam volume and stability were determined using a robotic pourer and computer vision algorithms. Modifications were applied to the protein determination method involving the use of yeast invertase as a standard in order to improve quantification accuracy. The protein content was found to be significantly correlated to parameters representative of foam stability, as were the amino acids arginine, asparagine, histidine, and tyrosine. Additionally, the production method was found to influence the foam collar height, which favored foaming in Méthode Traditionnelle wines over other those made by production methods. Understanding the contributions of key wine constituents to the visual and mouthfeel parameters of sparkling wine will enable more efficient production of high-quality wines.

Effects of Different Inoculation Regimes of Torulaspora delbrueckii and Oenococcus oeni on Fermentation Kinetics and Chemical Constituents of Durian Wine

This work evaluated the effects of inoculation time of Oenococcus oeni on the kinetics of fermentation and chemical constituents of durian wine produced using a non-Saccharomyces yeast, Torulaspora delbrueckii. The growth of T. delbrueckii in mixed-culture fermentations was significantly adversely affected by the presence of O. oeni, and the growth of malolactic bacteria was also affected by the metabolism of yeast during fermentation. The level of ethanol produced in simultaneous alcoholic and malolactic fermentation (SIM, 6.93%, v/v) was comparable to that in the Saccharomyces cerevisiae EC-1118 control (6.75%, v/v); both levels were relatively higher than that in the T. delbrueckii Biodiva control (6.39%, v/v) and the other two sequential fermentations (oenococci inoculated after four and seven days of alcoholic fermentation, SEQ 4th, 6.34% and SEQ 7th, 6.33% v/v respectively). The final concentrations of organic acids and esters in the mixed-culture wines were correlated with the inoculation time of O. oeni. SIM produced relatively higher levels of ethyl esters (ethyl esters of hexanoate, octanoate, decanoate and lactate) and acetate esters (ethyl acetate and isoamyl acetate) than those in SEQ 4th, SEQ 7th and the Biodiva control. This suggests that SIM would contribute fruity aroma properties to and modulate the mouthfeel of durian wine. The production of 3-(ethylthio)-1-propanol could compensate for the weak onion-like odour caused by the decrease in initial volatile sulphur compounds. Overall, this research suggests that SIM treatment is an effective way to produce durian wine with higher ester production.

STUDY INTO AN ALTERNATIVE TREATMENT METHOD TO SULPHUR DIOXIDE IN MULBERRY WINEMAKING

The characteristics of alcohol fermentation of mulberry juice treated under four different conditions of ultra-high pressure (100 MPa/10 min, 200 MPa/10 min, 300 MPa/10 min, 400 MPa/10 min), sulphur dioxide (60 mg/L), and a combination of ultra-high pressure and sulphur dioxide (30 mg/L) were assessed in this work. The volatile aroma constituents of mulberry wine made from mulberry juice using different treatments were isolated by solid phase microextraction (SPME) and identified by gas chromatography-mass spectrometry (GC-MS). A total of twenty five volatile aroma compounds of mulberry juice were identified, while nineteen volatile aroma compounds (five alcohols, four acids, and ten esters) were detected in mulberry wine. Ethyl acetate, butanoic acid ethyl ester, octanoic acid ethyl ester, acetic acid 2-phenylethyl ester, decanoic acid ethyl ester and ethyl 9-decenoate were the major esters and the main components of the mulberry wine, followed by 2-methyl, 1-propanol. Aldehydes were the major volatile fraction in mulberry wine, followed by alcohols. Pressure processing maintained the original flavour distribution of the juice. There were no significant differences among different mulberry wines in the types and concentrations of the volatile aroma components. It could be concluded that ultra-high pressure (300 MPa/10 min, 400 MPa/10 min) treatment could replace sulphur dioxide in winemaking in order to improve safety while maintaining the flavour compounds of mulberry wine.

Antioxidant and Antihypertensive Effects of a Chemically Defined Fraction of Syrah Red Wine on Spontaneously Hypertensive Rats.

A particularly phenolic-rich fraction extracted from red wine from the São Francisco valley (Northeastern Brazil) was chemically characterized and its hypotensive and antioxidant effects on spontaneously hypertensive rats were studied both in vitro and in vivo. The liquid-liquid pH dependent fractionation scheme afforded a fraction with high content of bioactive phenolics such as flavonols, flavonol glycosides, phenolic acids and anthocyanins, whose identities were confirmed by liquid chromatography coupled to mass spectrometry analysis. Pretreatment of spontaneously hypertensive rats with this wine fraction at doses of 50 and 100 mg/kg by gavage for 15 days was able to decrease mean arterial pressure and heart rate as well as decrease serum lipid peroxidation. The fraction at concentrations of 0.01–1000 µg/mL induced concentration-dependent relaxation of isolated rat superior mesenteric artery rings pre-contracted with phenylephrine and this effect was not attenuated by endothelium removal. Our results demonstrate it is possible for phenolic constituents of red wine that are orally bioavailable to exert in vivo hypotensive and antioxidant effects on intact endothelial function.

Mechanism of resveratrol-induced relaxation in the human gallbladder

BackgroundResveratrol is a polyphenolic compound extracted from plants and is also a constituent of red wine. Resveratrol produces relaxation of vascular smooth muscle and may prevent cardiovascular diseases. Although resveratrol has been reported to cause relaxation of the guinea pig gallbladder, limited data are available about the effect of resveratrol on the gallbladder smooth muscle in humans. The purpose of this study was to investigate the relaxation effects of resveratrol in human gallbladder muscle strips.MethodsWe studied the relaxant effects of resveratrol in human gallbladder. In addition, we also investigated mechanism of resveratrol-induced relaxation in human gallbladder by tetraethylammonium (a non-selective potassium channels blocker), iberiotoxin (an inhibitor of large conductance calcium-activated potassium channel), glibenclamide (an ATP-sensitive potassium channel blocker), charybdotoxin (an inhibitor of large conductance calcium-activated potassium channels and slowly inactivating voltage-gated potassium channels), apamine (a selective inhibitor of the small conductance calcium-activated potassium channel), KT 5720 (a cAMP-dependent protein kinase A inhibitor), KT 5823 (a cGMP-dependent protein kinase G inhibitor), NG-Nitro-L-arginine (a competitive inhibitor of nitric oxide synthase), tetrodotoxin (a selective neuronal Na+ channel blocker), and ω-conotoxin GVIA (a selective neuronal Ca2+ channel blocker).ResultsThe present study showed that resveratrol has relaxant effects in human gallbladder muscle strips. In addition, we found that resveratrol-induced relaxation in human gallbladder is associated with nitric oxide, ATP-sensitive potassium channel, and large conductance calcium-activated potassium channel pathways.ConclusionsThis study provides the first evidence concerning the relaxant effects of resveratrol in human gallbladder muscle strips. Furthermore, these results demonstrate that resveratrol is a potential new drug or health supplement in the treatment of biliary colic.

The Removal of Copper and Iron from Wine Using a Chelating Resin

An insoluble polymer-supported absorbant, developed for the selective removal of excess copper and iron from wine was tested. Tests conducted on dry white wine with excessive copper and iron showed effective removal of 98% copper (II) and 82 % iron (III). This treatment did not significantly affect the other wine constituents and therefore offers an appropriate alternative to the ferrocyanide treatment.

The Phenolic Composition of South African Pinotage, Shiraz and Cabernet Sauvignon Wines

Phenolic compounds are major constituents of red wines and impact on certain wine-quality parameters. This study has aimed to increase the knowledge base on the phenolic composition of South African red wines by HPLC quantification of 39 individual phenols and 2 polymeric, phenolic groups in 260 South African wines of the cultivars Pinotage, Shiraz and Cabernet Sauvignon. Statistical analysis of the collected data revealed significant cultivar differences in the levels of many of the analysed compounds, as well as in the ratios in which specific anthocyanins are found in the wines. These data may be helpful in the cultivar authentication of wines of these cultivars. Discriminant analysis of the data showed statistically significant separations of cultivars, based on their polyphenol composition, and also how the use of data from a specific wine-producing area or vintage improved the possibilities for successful authentication. The data were collected from both pure cultivar wines and commercial wines, which may contain up to 15 % of another cultivar wine. The collected data may therefore be further segmented into those obtained from pure cultivar wines and those obtained from blended wines in order to further enhance the accuracy of authentication of these respective groups of wines. The information obtained from this study opens several avenues for research on the impact of the noted cultivar differences on wine quality. Cultivar differences in the phenolic composition of young red wines also have important implications for the oenological management of oxidation reactions taking place during vinification and aging.

Lnfluence of grape variety, climate and soil on grape composition and on the composition and quality of table wines

The influence of grape variety, soil type, climatic area and year of vintage on grape composition and wine quality was studied over a six-year period with three grape varieties in a eo-operative investigation. The wines were made under carefully controlled conditions to eliminate, as far as possible, any effect of winemaking technique. All viticultural and oenological treatments were replicated so that the data could be analysed statistically. When grapes from different viticultural areas were made into table wines, the quality of the wines was most closely related to grape variety, followed by climatic area and least of all by soil type. Reproducible differences in grape and wine composition were found for the grape varieties studied. For fhe same sugar content Riesling grapes and wine contained more acidity and a higher tartaric acid/malic acid ratio than Clare Riesling grapes and wine. They also contained less nitrogen, phosphorus and potassium. Shiraz grapes were relatively high in malic acid. The year of vintage strongly influenced the tartaric acid/malic acid ratio, particularly for Riesling and Clare Riesling, and also certain other constituents. Certain years could be designated as either high or low malic acid years for a particular grape variety. The soil type influenced the amounts of certain of the constituents of grapes and wine, but had no significant effects on the wine quality. Wines from the same varieties grown on two widely different soils in the same area could not be differentiated in replicated taste tests. The soil depth, drainage and waterholding capacity appeared to be more important than composition per se . Wines made from irrigated vineyards in the warm River Murray viticultural region, contained similar amounts of tartaric and malic acids, but were higher in pH, than wines made from the same grape varieties in the cooler non-irrigated Barossa Valley. Wines from irrigated grapes were generally of somewhat lower quality than those made from grapes of the same variety grown without irrigation in a cooler area. The time of harvesting irrigated grapes appeared to be critical to achieve the necessary balance between sugar, acid and flavour. Shiraz grapes grown under irrigation contained considerably less colour than grapes of the same variety grown without irrigation. Aroma was correlated with flavour in assessing wine quality, but numerical values ascribed to these parameters did not correlate generally with the wine constituents measured. A positive correlation existed between high tasting scores and high Ball/acid ratio.

Combined effects of fermentation temperature and pH on kinetic changes of chemical constituents of durian wine fermented with Saccharomyces cerevisiae.

This study investigated the effects of temperature (20 and 30°C) and pH (pH3.1, 3.9) on kinetic changes of chemical constituents of the durian wine fermented with Saccharomyces cerevisiae. Temperature significantly affected growth of S. cerevisiae EC-1118 regardless of pH with a higher temperature leading to a faster cell death. The pH had a more significant effect on ethanol production than temperature with higher production at 20°C (5.95%, v/v) and 30°C (5.56%, v/v) at pH3.9, relative to that at pH3.1 (5.25 and 5.01%, v/v). However, relatively higher levels of isobutyl alcohol and isoamyl alcohol up to 64.52±6.39 and 56.27±3.00mg/L, respectively, were produced at pH3.1 than at pH3.9 regardless of temperature. In contrast, production of esters was more affected by temperature than pH, where levels of ethyl esters (ethyl esters of octanoate, nonanoate, and decanoate) and acetate esters (ethyl acetate and isoamyl acetate) were significantly higher up to 2.13±0.23 and 4.61±0.22mg/L, respectively, at 20°C than at 30°C. On the other hand, higher temperature improved the reduction of volatile sulfur compounds. This study illustrated that temperature control would be a more effective tool than pH in modulating the resulting aroma compound profile of durian wine.

Advances in post-fermented wine clarification by centrifugal technology

Wine clarification processes are deeply determined by complex interaction of wine constituents and application of available technologies as well as use of fining agents. Among others, centrifuge is a consolidated technique applied for many separation duties in the winery. Important advances on improvement of the performance of centrifugal technology have beeen focused on gentle wine treatment, minimal dissolved oxygen and significant reduction of energy consumption helping to dispel old beliefs on a technique considered to be traditional. This paper reviews the development of technology and recent advances on centrifuge improvement and aims to show, through field experimental observation, the importance of removing a portion of particles responsible of haze in the light of very low level of dissolved oxygen and complementarity of alternative recent techniques of wine filtration like cross-flow microfiltration.

Advances in post-fermented wine clarification by centrifugal technology

Wine clarification processes are deeply determined by complex interaction of wine constituents and application of available technologies as well as use of fining agents. Among others, centrifuge is a consolidated technique applied for many separation duties in the winery. Important advances on improvement of the performance of centrifugal technology have beeen focused on gentle wine treatment, minimal dissolved oxygen and significant reduction of energy consumption helping to dispel old beliefs on a technique considered to be traditional. This paper reviews the development of technology and recent advances on centrifuge improvement and aims to show, through field experimental observation, the importance of removing a portion of particles responsible of haze in the light of very low level of dissolved oxygen and complementarity of alternative recent techniques of wine filtration like cross-flow microfiltration.