Effects of the treatment with oak chips on color-related phenolics, volatile composition, and sensory profile of red wines: the case of Aglianico and Montepulciano

Low-pressure continuous dynamic extraction from oak chips combined with passive micro-oxygenation to tune red wine properties

Static infusion of oak chips in wine is a common practice during wine ageing, aimed at improving sensory properties and stability of wines. The wine/chips contact required to reach the desired effect can last several weeks or months. A low-pressure continuous dynamic (LPCD) extractor in which a closed-circle, low-pressure continuous flow of wine passes through an extraction cell filled with chips, was evaluated as a tool to tune red wine properties in few hours. The aim of this work was to evaluate the effect of the use of a LPCD extractor the effect on color, volatile compounds and sensory properties of a Primitivo wine, as well as to assess the combined effect of LPCD extractor, passive microxygenation through polyethylenetereftalate (PET) containers and exogenous tannins. Their combined effect caused a significant increase of stabilized pigments was observed, without compromising the aroma profile. LPCD extraction, passive micro-oxygenation through plastic materials and enological tannins can be considered as a low-cost, and potentially low-impact, integrated technological platform suitable to tune wine sensory properties and stability, when either traditional approaches (such as barrel aging) or other assisted extraction technologies are not applicable or preferred, even in small wineries.

The Influence of Active Compounds of Chips Made from Different Wood Species on the Antioxidant, Oenological and Sensory Properties of Apple Wines

Wood chips contain numerous active compounds that can affect the wine's characteristics. They are commonly used in red grape wines, whisky, cherry and brandy, but in fruit wines, production is not typically utilised. The aim of this study was to compare the impact of an oak barrel ageing with the effect of the addition of chips made from various types of wood (oak, maple, cherry, apple) and with various degrees of toasting to the apple wines on their antioxidant, oenological and sensory properties. The oenological parameters, the polyphenols content, antioxidant activity and content of volatile odour-active compounds were assessed. It was shown that ageing in the presence of wood chips had a less noticeable effect on the oenological and sensory parameters of the wine than barrel ageing. Moreover, wood chips used did not significantly affect the acidity, alcohol and extract content of apple wines. Wines aged in the presence of oak chips (particularly lightly toasted) exhibited the greatest increase in polyphenols, while the polyphenol content of wines aged in the presence of other chips was not dependent on their toasting degree. The ageing of fruit wines with wood chips influences the volatile profile and the olfactory sensations, which can improve their quality.

Application of toasted vine-shoot chips and ultrasound treatment in the ageing of Primitivo wine

Ageing wine in barrels is an historical practice used to improve the aromatic complexity of wine, but due to the high cost and the long ageing period, alternative approaches have been developed, such as the use of wood chips and ultrasound treatment. The present paper reports the results of an investigation performed on wine (cv. Primitivo). Three treatments were investigated: a) control wine untreated; b) wine with toasted vine-shoot chips (10 g/L); c) wine with toasted vine-shoot chips (10 g/L) and treated by ultrasound. Wines were analysed after 7, 14, 21, and 28 days. The application of ultrasound combined with vine-shoot chips promoted tannin evolution, thereby accelerating the ageing process of wine. The chips addition decreased the total anthocyanins content and increased the stilbenes (trans-resveratrol and trans-piceid) and wood-related aromas (i.e., furfural, 5-methylfurfural) concentration. Finally, wines added with chips were richer in woody, vanilla, oak, and chocolate notes and more preferred by the tasters.

The Impact of Compounds Extracted from Wood on the Quality of Alcoholic Beverages

The production of some alcoholic beverages very often requires the use of wood from various tree species to improve the quality parameters (smell, taste, and color) of the drink. The review discusses the types of wood used in the production of wines, beers, and flavored vodkas. Changes occurring in wood during the process of toasting barrels or wood chips are described. The compounds derived from wood that shape the aroma, taste, and color of alcoholic beverages are presented. Depending on their origin, they were classified into compounds naturally occurring in wood and those formed as a result of the thermal treatment of wood. Next, the influence of the presence of wood on the quality of alcoholic beverages was described, with particular emphasis on wine, beer, whisky, and brandy. The final part of the article presents innovative techniques using wood to impart qualitative features to alcoholic beverages.

Application of Vine-Shoot Chips during Winemaking and Aging of Malbec and Bonarda Wines

The growing demand in recent years for sustainable wine production has led to the management of waste and by-products. Among them, vine-shoots could be used as additives comparable to the oak fragments widely employed in enology. This work analyzes the feasibility of applying vine-shoot chips during winemaking and the aging of Malbec and Bonarda wines from Mendoza (Argentina) and evaluates their chemical and sensory impact. Toasted (CHT) and untoasted (CHWT) vine-shoot chips obtained from a Bonarda vineyard were added in Malbec and Bonarda grapes during winemaking (Experiment A): C, control; CHWT, 12 g/L; CHT, 12 g/L. Furthermore, the same treatments were applied during aging (1M, 30 days; 2M, 60 days; 4M, 120 days) to the finished wines under controlled conditions (Experiment B). The impact of vine-shoot chips during winemaking was different between varieties. For Malbec alone, CHT caused a significant decrease in tannins, anthocyanins, and polymeric pigments, and a modification of wine color. During aging, CHWT and CHT had an impact mainly at the sensory level, increasing the wine’s complexity in terms of aromatic attributes and mouthfeel. In conclusion, the proposed technology could be a simple and economical tool for red wine production of high chemical and organoleptic quality.

Phenolic Compounds as Markers of Wine Quality and Authenticity

Targeted and untargeted determinations are being currently applied to different classes of natural phenolics to develop an integrated approach aimed at ensuring compliance to regulatory prescriptions related to specific quality parameters of wine production. The regulations are particularly severe for wine and include various aspects of the viticulture practices and winemaking techniques. Nevertheless, the use of phenolic profiles for quality control is still fragmented and incomplete, even if they are a promising tool for quality evaluation. Only a few methods have been already validated and widely applied, and an integrated approach is in fact still missing because of the complex dependence of the chemical profile of wine on many viticultural and enological factors, which have not been clarified yet. For example, there is a lack of studies about the phenolic composition in relation to the wine authenticity of white and especially rosé wines. This review is a bibliographic account on the approaches based on phenolic species that have been developed for the evaluation of wine quality and frauds, from the grape varieties (of V. vinifera and non vinifera), to the geographical origin, the vintage year, the winemaking process, and wine aging. Future perspectives on the role of phenolic compounds in different wine quality aspects, which should be still exploited, are also outlined.

Evaluation of Aroma Compounds in the Process of Wine Ageing with Oak Chips

Many modern alcoholic beverages are subjected to ageing processes during which compounds extracted from wood contribute decisively to the overall beverage character. Wines represent a perfect example of beverage in which ageing is a crucial technological manufacturing step. During winemaking, producers accelerate chemical changes in wine composition by traditional and alternative methods, such as the use of oak wood barrels and/or oak wood chips. Our research aimed to investigate the overall volatile composition and sensory quality of red wines aged for two timeframes, namely, 1.5 and 3 months, and with two technological variants, i.e., American and French oak wood chips. Red grapes from the Fetească neagră (Vitis vinifera) variety were harvested from a vineyard in the North-East region of Romania. Stir bar sorptive extraction and gas chromatography coupled with mass spectrometry (SBSE-GC-MS) was used to extract minor aromas present in wine samples. The results showed clear differences between wines treated with American and French oak chips. Furthermore, ageing for 3 months increased the concentration of cis-whiskey lactone and guaiacol in American oak-treated wine samples. For wines aged with French oak chips, we observed higher concentrations of furfural, 5-methylfurfural, 4-vinylguaiacol, and trans-whiskey lactone. The increased presence of chemical compounds in wine aged with French oak chips generated prominent smoky, licorice, and toasty aromas, whereas in wines aged with American oak chips, notes of vanilla, toasty, and cacao aromas were noticed. Moreover, red wines aged with American and French oak chips were discriminated by chemometric analysis, which confirmed the evolution of aroma compounds.

Volatolomics approach by HS-SPME-GC-MS and multivariate analysis to discriminate olive tree varieties infected by Xylella fastidiosa

INTRODUCTION

Xylella fastidiosa (Xf) is a pathogenic bacterium that causes diseases in olive trees. Therefore, analytical methods for both the characterisation of the host/pathogen interaction and infection monitoring are needed. Volatile organic compounds (VOCs) are emitted by plants relate to their physiological state, therefore VOCs monitoring can assist in detecting stress or infection states before visible signs are present.

OBJECTIVE

In this work, the headspace-solid phase microextraction-gaschromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the first time to highlight VOCs differences between healthy and Xf-infected olive trees.

METHODOLOGY

VOCs from olive tree twig samples were extracted and analysed by HS-SPME-GC-MS, and hence identified by comparing the experimental linear retention indexes with the reference values and by MS data obtained from NIST library. Data were processed by principal component analysis (PCA) and analysis of variance (ANOVA).

RESULTS

The HS-SPME step was optimised in terms of adsorbent phase and extraction time. HS-SPME-GC-MS technique was applied to the extraction and analysis of VOCs of healthy and Xf-infected olive trees. More than 100 compounds were identified and the differences between samples were evidenced by the multivariate analysis approach. The results showed the marked presence of methyl esters in Xf-infected samples, suggesting their probable involvement in the mechanism of diffusible signal factor.

CONCLUSION

The proposed approach represents an easy and solvent-free method to evaluate the presence of Xf in olive trees, and to evidence volatiles produced by host/pathogen interactions that could be involved in the defensive mechanism of the olive tree and/or in the infective action of Xf.

Volatilome fingerprint of red wines aged with chips or staves: Influence of the aging time and toasting degree

The influence on aroma compounds chips or staves and toasting degree have been analyzed in red wines aged for two periods of time. Ethyl propanoate, ethyl butanoate, ethyl octanoate, ethyl acetate, isoamyl acetate, isobutanol, 2-methyl-1-butanol, 2-phenylethanol, E-2-hexenol, octanal, nonanal, decanal, γ-nonalactone, furfural, 5-methylfurfural, 2-methoxy-4-vinylphenol and cis-whiskey lactone were the compounds that contribute the most to the aroma series profile. By means of principal components analysis, esters were related to the aging time; cis-whiskey lactone with the type of wood pieces and octanal, 5-methyl furfural and cis-whiskey lactone with the toasting degree. Star plot show that woody aroma compounds are dominant in wines aged with low toasting degree oak pieces, whereas medium plus toasted pieces increased the concentration of aroma compounds with fruity aroma descriptors. Wines with prominent fruity or woody aromas can be obtained depending upon the degree of toasting of wood pieces used for aging.