Recovery of Polysaccharides from Red Grape Marc and White Grape Pomace by Degradation of Cell Walls by Enzymes with Different Activities.

The recovery of polysaccharides (PS) from red grape marc and white grape pomace by enzymatic degradation of their cell walls is an interesting green extraction technique that preserves the structure and bioactivity of PS. The type and dose of enzyme, and the liquid/solid (L/S) ratio in PS extraction were studied using four commercial enzymes. Four different doses per enzyme were used, with tartaric acid as solvent and L/S ratios of 1.

The Influence of Geographical Location and Aging Time on the Chemical and Sensory Quality of Tempranillo Wines.

The changes produced during the aging of wines in oak barrels are strongly dependent on the oak's geographical origin and aging time. This paper analyzes the effect of oak from four different geographical locations in four states in the USA, namely Missouri (Mo), Ohio (Oh), Kentucky (Kt), and Pennsylvania (Py), during 24 months of aging. Oak origin had a higher effect on the wine's aromatic composition than the polyphenolic one.

The Generation of Suspended Cell Wall Material May Limit the Effect of Ultrasound Technology in Some Varietal Wines.

The disruptive effect exerted by high-power ultrasound on grape cell walls enhances phenolic extraction, improving chromatic characteristics during red wine maceration. However, short maceration times may, sometimes, hinder this enhancement, and this effect could be attributed to the suspended cell wall material formation facilitated by sonication. This suspended material, having a strong affinity for phenolic compounds, can lead to their precipitation and elimination during subsequent vinification stages and, consequently, a significant portion of extracted phenolic compounds may not contribute to the final phenolic composition of the wine, impacting its chromatic features.

Chemical Characterization of Polysaccharide Extracts Obtained from Pomace By-Products of Different White Grape Varieties.

Grape pomace is one of the main by-products in the wine industry and contains some high-added-value compounds, such as polysaccharides. Considering the wide application possibilities of polysaccharides in wine and in the food industry, the revalorization of grape pomace to extract polysaccharides presents itself as an opportunity for by-product management. Therefore, the aim of this study was to characterize polysaccharide extracts obtained from pomace by-products of different white grape varieties.

Grape-Derived Polysaccharide Extracts Rich in Rhamnogalacturonans-II as Potential Modulators of White Wine Flavor Compounds.

Many authors have investigated the role of mannoproteins on wine quality, but very few have analyzed the use of grape-derived polysaccharides as they are not commercially available. In this study, purified grape-derived polysaccharides from red wine (WPP) and winemaking by-products (DWRP: Distilled Washing Residues Polysaccharides) were used as potential fining agents to modulate white wine flavor. Phenolics and volatile compounds were analyzed in the control and wines treated with WPP, DWRP, and commercial mannoproteins (CMs) after one and twelve months of bottling, and a sensory analysis was conducted.

Influence of Grape Polysaccharide Extracts on the Phenolic Compounds and Color Characteristics of Different Red Wines.

Polysaccharides have an important role in the technological and sensory characteristics of wines. The aim of this work was to study the effects of the addition of four polysaccharide extracts obtained from grape products and byproducts to red wines during storage for 2 months on their phenolic composition and color. The four extracts rich in polysaccharides were obtained from grape must, white grape pomace, red grape marc, and red wine, and they were compared with a commercial inactivated yeast.

Potential use of grape and wine polysaccharide extracts as fining agents to modulate the volatile composition of Viura wines.

This paper describes for the first time the use of grape derived polysaccharide extracts as potential fining agents to modulate the volatile composition of Viura white wines. Polysaccharide extracts were obtained from white grape pomace, red wine pomace, white must, red must, white wine, and lees from white wine. Except for higher alcohols, the extracts from white pomace, red pomace and white lees increased the content of most volatile compounds after one and twelve months of bottle aging.

High-Power Ultrasound in Enology: Is the Outcome of This Technique Dependent on Grape Variety?

The disruptive effect exerted by high-power ultrasound (US) on grape cell walls is established as the reason behind the chromatic, aromatic and mouthfeel improvement that this treatment causes in red wines. Given the biochemical differences that exist between the cell walls of different grape varieties, this paper investigates whether the effect of the application of US in a winery may vary according to the grape variety treated. Wines were elaborated with Monastrell, Syrah and Cabernet Sauvignon grapes, applying a sonication treatment to the crushed grapes using industrial-scale equipment.

Effect of Pre-fermentative Treatments on Polysaccharide Composition of White and Rosé Musts and Wines.

This paper studied the effect of conventional pre-fermentative techniques (direct pressing "CP" and cold maceration "CM") and an innovate technique (high power ultrasounds "S"), applied to Viogner and Monastrell grapes on the polysaccharide content of the musts, white and rosé wines, and after six months of bottle aging. The results showed that the longer pre-fermentation maceration time applied with the CM technique compared to the short ultrasonic maceration was key in the extraction of polysaccharides from the grape to the must. CP treatment produced wines with the lowest content of total soluble polysaccharide families since it was the least intense pretreatment for the disruption of the grape berry cell wall polysaccharides.

The Effects of Grape Polysaccharides Extracted from Grape By-Products on the Chemical Composition and Sensory Characteristics of White Wines.

There is an increasing interest in the valorization of wine waste by-products. Grape pomace/marc can be an important source of polyphenols but also of polysaccharides (PSs). Therefore, the aim of this work was to extract PSs from grape pomace and musts and incorporate them into wines to improve their quality and valorize these residues.

Characterization of polysaccharide extracts recovered from different grape and winemaking products.

One of the most important challenges of the oenological industry is the recovery and valorization of valuable compounds from grapes and grape by-products. Recent studies have focused on the obtention of phenolic compounds, but little attention has been paid to the extraction of grape polysaccharides, which could have a great potential as oenological products but also for their benefits to human health. This study aimed to recover polysaccharides from different grape and winemaking products and provide information about its composition.

Use of Microwave Maceration in Red Winemaking: Effect on Fermentation and Chemical Composition of Red Wines.

The objective of this study was to evaluate the effect of microwave treatment of crushed grapes on the yeast population of the must and on the development of alcoholic fermentation, as well as on the extraction of different compounds from the grapes such as polysaccharides and amino acids that can affect the organoleptic quality and stability of the wine. This study demonstrated for the first time the effect of the microwave treatment of grapes on native yeast species and their diversity, producing an increase in fermentation kinetics and a decrease in the lag phase. The microwave treatment produced a positive effect on the extraction of amino acids and polysaccharides from the grapes, resulting in significantly higher amounts of the main amino acids of the must and some major volatile compounds in the treated samples.

Effect of Sonication Treatment and Maceration Time in the Extraction of Polysaccharide Compounds during Red Wine Vinification.

The application of high-power ultrasounds (US) at 28 kHz to the crushed grapes and the use of different pomace contact times caused changes in the content and composition of monosaccharides and polysaccharides in the musts and wines. These differences were maintained from the moment of pressing (end of maceration) until the end of the alcoholic fermentation. The US increased the content of monosaccharides and polysaccharides in the musts by facilitating their extraction from the solid parts during maceration.

Optimization of a method to extract polysaccharides from white grape pomace by-products.

The aim of this paper is to optimize a method to recover polysaccharides from white grape pomace (non-fermented), the main waste by-product of the food industry. Different conditions are tested and the polysaccharides extracted are analyzed by high performance size exclusion chromatography with refractive index detector (HPSEC-RID) and gas chromatography with mass detector (GC-MS). The extraction solvent did not show a significant effect on the polysaccharide extraction, acid pH yielded to higher efficiencies, and longer extraction times extracted more smaller polysaccharides (≤5.

Ultrasound treatment of crushed grapes: Effect on the must and red wine polysaccharide composition.

This paper studied the effect on the molecular weight and polysaccharide composition of musts and wines of the application of high-power ultrasound (US) at 20 and 28 kHz on crushed grapes. Two different pomace maceration times (short and mid) were tested for sonicated and control vinifications. A long pomace maceration time was also tested for non-treated wines.

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

The study of seaweeds is increasing in viticulture due to their implications on plant protection and grape quality. This trial aimed to study the effects of foliar applications of an Ascophyllum nodosum extract at low (0.25%, v v) and high (0.

Evaluation of grape ripeness, carbonic maceration and pectolytic enzymes to improve the chemical and sensory quality of red sparkling wines.

Background: Red sparkling wines are and innovative product for the oenology market, and oenologists are looking for technologies to improve their winemaking. The present study aimed to use both carbonic maceration and pectolytic enzymes applied to premature grapes during the winemaking of red sparkling wines. Both could modify the release of polyphenols, as well as improve the foaming, aroma and sensory properties of the wines.

Effects of different oenological techniques on the elaboration of adequate base wines for red sparkling wine production: phenolic composition, sensory properties and foam parameters.

Background: In red sparkling winemaking it is essential to obtain base wines with moderate alcohol content, adequate mouthfeel and color intensity. The aim of this work was to study oenological techniques to obtain adequate base wines for production of red sparkling wine by traditional methods: pre-fermentative cold maceration with dry ice and délestage with premature grapes; and sugar reduction in must and partial dealcoholisation of wine with mature grapes. The effect on oenological parameters, e.

Effect of the winemaking process on the volatile composition and aromatic profile of Tempranillo Blanco wines.

The effects of the carbonic maceration and conventional winemaking on the volatile composition and aromatic sensory characteristics of Tempranillo Blanco wines were studied for the first time, during three consecutive vintages. Relationships between instrumental (volatiles) and sensory variables were analyzed applying partial least squares regression (PLS). Carbonic macerated wines had higher contents of alcohols and carbonyl compounds, yet lower concentrations of C alcohols and volatile acids than wines conventionally produced.

Polysaccharides, oligosaccharides and nitrogenous compounds change during the ageing of Tempranillo and Verdejo sparkling wines.

Background: Verdejo and Tempranillo are traditional varieties for producing still wines; however, they could provide an alternative for the manufacturing of sparkling wines. Sparkling wines were elaborated by the traditional method, followed by ageing on lees for 9 months. A study on the changes that take place in polysaccharides, oligosaccharides and nitrogenous compounds during the ageing on lees of Tempranillo and Verdejo sparkling wines has been undertaken.

Effect of egg albumin fining, progressive clarification and cross-flow microfiltration on the polysaccharide and proanthocyanidin composition of red varietal wines.

The effect of egg albumin fining, progressive clarification and cross-flow microfiltration on the polysaccharide and proanthocyanidin composition of four red varietal wines was studied in this work. Discriminant analyses were applied to achieve a possible differentiation of the wines according to treatment or grape variety. Egg albumin fining did no produce a significant decrease in the content of wine polysaccharides.

Influence of Grape Maturity on Complex Carbohydrate Composition of Red Sparkling Wines.

This paper studied how grape maturity affected complex carbohydrate composition during red sparkling wine making and wine aging. Grape ripening stage (premature and mature grapes) showed a significant impact on the content, composition, and evolution of polysaccharides and oligosaccharides of sparkling wines. Polysaccharides rich in arabinose and galactose, mannoproteins, rhamnogalacturonans II, and oligosaccharides in base wines increased with maturity.

Use of Commercial Dry Yeast Products Rich in Mannoproteins for White and Rosé Sparkling Wine Elaboration.

In sparkling wines, mannoproteins released during yeast autolysis largely affect their final quality. This process is very slow and may take several months. The aim of this work was to study the effect of several commercial dry yeast autolysates on the chemical composition, foam, and sensory properties of white and rosé sparkling wines aged on lees for 9 months during two consecutive vintages.

First-line eradication rates comparing two shortened non-bismuth quadruple regimens against Helicobacter pylori: an open-label, randomized, multicentre clinical trial.

Objectives: Helicobacter pylori eradication remains a challenge. Non-bismuth-based quadruple regimens (NBQR) have shown high eradication rates (ER) elsewhere that need to be locally confirmed. The objective of this study was to compare the first-line ER of a hybrid therapy (20 mg of omeprazole twice daily and 1 g of amoxicillin twice daily for 10 days, adding 500 mg of clarithromycin twice daily and 500 mg of metronidazole every 8 h for the last 5 days; OA-OACM) with that of a 10 day concomitant regimen consisting of taking all four drugs twice daily every day (including 500 mg of metronidazole every 12 h; OACM).