A comparative study of partial dealcoholisation versus early harvest: Effects on wine volatile and sensory profiles

Dealcoholized wine: Techniques, sensory impacts, stability, and perspectives of a growing industry

The category of dealcoholized wine is receiving mounting interest within the wine industry related to the ability to retain sensory characteristics similar to regular wine while reducing or completely removing the alcohol level. This option has led health-conscious consumers to seek a lower alcohol alternative without compromising the authentic wine experience. This review provides a comprehensive overview of the various dealcoholization techniques that are being used in the production of dealcoholized and partial dealcoholized wine, specifically examining reverse osmosis, osmotic distillation, vacuum distillation, spinning cone column, pervaporation, and diafiltration along with the effects of these methods on chemical and sensory characteristics of wine, involving flavor, aroma, mouthfeel, and finish. Various aspects of the impact of dealcoholization on wine stability were explored, including chemical, microbial, oxidative, and color stability. Furthermore, the market analysis of dealcoholized wine products including present and future growth in different regions is reported. Understanding these factors is of utmost importance for dealcoholized wine's growing advancement and market success, as it endeavors to accommodate various customer demands and preferences in a swiftly changing beverage environment.

Non-Alcoholic Wines: Sensory Pleasantness and Health Benefits

Non-alcoholic wine is becoming popular as a healthier alternative to traditional wine, offering potential health benefits without the risks of alcohol consumption. Sensory attributes, such as taste and aroma, significantly influence consumer preferences, with sweet, sour, and balanced fragrances favored over bitter or medicinal notes. A lower alcohol content can enhance the complexity of sensory properties, suggesting that non-alcoholic wines provide an appealing experience. Moderate consumption, particularly of red wine, has been linked to reduced cardiovascular mortality, attributed to phenolic compounds like resveratrol and quercetin present in both alcoholic and non-alcoholic wines. These bioactive components are associated with reduced risks of chronic diseases by modulating biochemical pathways and gene expression. Health-conscious consumers are increasingly taking these benefits into account in their purchasing decisions. Non-alcoholic wines may appeal to individuals seeking health benefits without the presence of alcohol. While some evidence supports the health advantages of wine, most research is observational, and the specific benefits of non-alcoholic options need further investigation. Challenges include isolating the effects of wine's bioactive compounds from other factors and creating appealing non-alcoholic wines through innovative fermentation techniques, such as using non-Saccharomyces yeast strains. Overall, non-alcoholic wine holds promise for those seeking sensory and health benefits without alcohol, highlighting the need for ongoing research and innovation in production methods to enhance its appeal and validate its benefits. Based on recent findings, this review will examine the sensory qualities and health benefits of non-alcoholic wine.

On-vine drying (passérillage) improves the quality of "Hutai No. 8" table grape wine: Focusing on phenolics, aromas, color and sensory attributes

On-vine drying (passérillage) was employed for Hutai No.8 table grapes with different water loss rates and that are used for winemaking to alter the qualities of wine. Results showed that on-vine drying increased sugar content, thereby elevating alcohol and glycerol contents in the resulting wine. A moderate drying treatment (D2, 18 % water loss) produced wine with optimal red color characteristics. The D2 wine contained abundant individual phenolics such as caffeic acid, salicylic acid, resveratrol, p-coumaric acid, and proanthocyanidin B1, which exhibited strong positive correlations with color parameters (a⁎, C*ab and △E*ab). Similar trends were observed in aroma compounds, with ethyl acetate, ethyl caproate, diethyl succinate, geraniol, linalool, 4-terpinenol, α-terpineol, and β-ionone contents showing significant increment in D2, aligning with enhanced sensory evaluations of wines. Thus, improvement of wine quality can be achieved through moderate on-vine drying (18 % water loss)，serving as a valuable reference for table grape winemaking.

Comparison of pre-fermentation and post-fermentations alcohol adjustments on aromatic chemistry and sensory composition of Sauvignon blanc wine

Harvest and alcohol adjustment effects were evaluated for Sauvignon blanc grapes harvested at three potential alcohols (11, 13 and 15% (v/v)) by gas chromatography-mass spectrometry and descriptive analysis. Alcohol concentration was controlled for pre-fermentation by dilution or chaptalization and post-fermentation by dealcoholization. The initial experimental alcohol was treated as the control and the dealcoholized wine the treatment. Wine treatments sharing the same alcohol target and harvest date as the dealcoholized wine were designated as the negative control. All aroma compounds measured increased because of higher ethanol or declined because of dealcoholization. Similar aroma concentrations were observed to be a factor of alcohol concentration, apart from volatile thiols which were influenced by harvest. Statistical analysis of sensory and aroma compounds showed a corresponding relationship between low versus high alcohol wines. Dealcoholization appears to be an effective tool for altering wine aroma and winemaking style with comparable aroma loss to pre-fermentation adjustment.

Profile of red wine partially dealcoholized with a membrane-based technique and strategies to mitigate the loss of volatile compounds

In recent years, climate change has led to higher grape must sugar content and, consequently, increased alcohol by volume. Evaporative or pertraction is a common method for post-fermentation ethanol removal from wines, but it selectively removes some less polar volatile compounds along with ethanol. To mitigate volatile substance loss, this study investigates blending of the red wine (Marzemino-Cabernet blend) with obtained dealcoholized samples from it by industrial evaporative pertraction system, while maintaining the final product within a two-percentage-point reduction in ethanol. Thus MIX 1 and MIX 2 blends were prepared, reducing the ABV of the initial wine (12.5% alcohol by volume) to 10.5% and 9.5%. Chemical analyses highlighted that most alcohols, acetates, and ethyl esters of fatty acids decreased with alcohol by volume reduction. However, compounds with polar groups (acetoin and acetovanillone), C13-norisoprenoids, and certain lactones showed increasing trends. Sensory analysis indicated high scores for sweetness and smoothness in the blended wines, with a decrease in acidic taste. Floral scents notably increased, particularly in MIX 2, closely resembling the initial wine's sensory profile. The blending of initial wine with appropriately dealcoholized wine samples has proven to be an effective strategy for preserving bouquet and color of dealcoholized wines. This approach broadens the consumer base by catering to people who prefer low-alcohol options, have dietary restrictions, or are health-conscious, but who still wish to savor wines with aromatic quality rather than a flat taste. This strategy is crucial in the wine industry as it successfully addresses technical challenges and ensures economic viability.

Yeast or water: producing wine with lower alcohol levels in a warming climate: a review

Climate change effects over the last century have seen grape wine growers being faced with earlier budburst and shorter seasons. One effect is higher sugar levels in the grape berries, resulting in wines with higher than typical alcohol concentrations. Winemakers, both in Australia and globally, need to reassess their wine making approaches to address the challenges associated with warmer drier conditions. This review focuses on two pre-fermentation approaches that address ethanol production during fermentation, so that wine makers can produce a wine with lower final alcohol levels at the same time as addressing any negative impacts on wine quality. First, microbiological yeast approaches are reviewed. This approach can reduce final alcohol levels in a treated wine between 0.2% v/v-3.7% v/v; however, diverse wine quality impacts can result, dependant on the microbiological yeast approach taken. Second, the pre-fermentation approach of water addition/substitution into a high sugar grape must is reviewed. To date, recent studies indicate that this 'water treatment' of musts approach is effective with respect to reducing final alcohol levels from between 0.6% v/v-5.9% v/v in the resultant wines, with less variation effects on final wine quality. It is noted that further studies for the 'water treatment' of high sugar musts approach are required to provide additional foundational data sets with respect to impacts on chemical, phenolic and sensory attributes of the final wine products, both within and across vintages. This is especially important as winemakers adapt their winemaking approaches in a changing climate. © 2022 Society of Chemical Industry.

A Sustainable Approach Based on the Use of Unripe Grape Frozen Musts to Modulate Wine Characteristics as a Proof of Concept

Aiming to develop a sustainable methodology for must acidity correction in winemaking, particularly needed in warm regions, the present study intends to fulfill the circular economy values. Antão Vaz white wines were produced using two different strategies for must acidity correction: (i) the addition of a mixture of organic acids (Mix*) commonly used in winemaking; and (ii) the addition of previously produced unripe grape must (UM*) from the same grape variety. In addition, a testimonial (T*) sample was produced with no acidity correction. For all wines produced, oenological parameters were determined, and both amino acid (AA) content and volatile composition were evaluated. A higher AA content was found in the Antão Vaz T* wine, followed by UM* wines. The volatile profile was also affected, and LDA demonstrates a clear separation of wines with different acidity corrections. Results obtained indicate that unripe grape musts—a vital waste product containing several compounds with important biological activity—can be used to increase musts acidity without a negative impact on wine characteristics. Furthermore, this work also shows that the use of unripe must may be a valuable tool for reducing the alcoholic content of wines.

Advances in White Wine Protein Stabilization Technologies

The unstable proteins in white wine cause haze in bottles of white wine, degrading its quality. Thaumatins and chitinases are grape pathogenesis-related (PR) proteins that remain stable during vinification but can precipitate at high temperatures after bottling. The white wine protein stabilization process can prevent haze by removing these unstable proteins. Traditionally, bentonite is used to remove these proteins; however, it is labor-intensive, generates wine losses, affects wine quality, and harms the environment. More efficient protein stabilization technologies should be based on a better understanding of the main factors and mechanisms underlying protein precipitation. This review focuses on recent developments regarding the instability and removal of white wine proteins, which could be helpful to design more economical and environmentally friendly protein stabilization methods that better preserve the products´ quality.

Techniques for Dealcoholization of Wines: Their Impact on Wine Phenolic Composition, Volatile Composition, and Sensory Characteristics

The attention of some winemakers and researchers over the past years has been drawn towards the partial or total dealcoholization of wines and alcoholic beverages due to trends in wine styles, and the effect of climate change on wine alcohol content. To achieve this, different techniques have been used at the various stages of winemaking, among which the physical dealcoholization techniques, particularly membrane separation (nanofiltration, reverse osmosis, evaporative perstraction, and pervaporation) and thermal distillation (vacuum distillation and spinning cone column), have shown promising results and hence are being used for commercial production. However, the removal of alcohol by these techniques can cause changes in color and losses of desirable volatile aroma compounds, which can subsequently affect the sensory quality and acceptability of the wine by consumers. Aside from the removal of ethanol, other factors such as the ethanol concentration, the kind of alcohol removal technique, the retention properties of the wine non-volatile matrix, and the chemical-physical properties of the aroma compounds can influence changes in the wine sensory quality during dealcoholization. This review highlights and summarizes some of the techniques for wine dealcoholization and their impact on wine quality to help winemakers in choosing the best technique to limit adverse effects in dealcoholized wines and to help meet the needs and acceptance among different targeted consumers such as younger people, pregnant women, drivers, and teetotalers.

Production, Consumption, and Potential Public Health Impact of Low- and No-Alcohol Products: Results of a Scoping Review

Switching from higher strength to low- and no-alcohol products could result in consumers buying and drinking fewer grams of ethanol. We undertook a scoping review with systematic searches of English language publications between 1 January 2010 and 17 January 2021 using PubMed and Web of Science, covering production, consumption, and policy drivers related to low- and no-alcohol products. Seventy publications were included in our review. We found no publications comparing a life cycle assessment of health and environmental impacts between alcohol-free and regular-strength products. Three publications of low- and no-alcohol beers found only limited penetration of sales compared with higher strength beers. Two publications from only one jurisdiction (Great Britain) suggested that sales of no- and low-alcohol beers replaced rather than added to sales of higher strength beers. Eight publications indicated that taste, prior experiences, brand, health and wellbeing issues, price differentials, and overall decreases in the social stigma associated with drinking alcohol-free beverages were drivers of the purchase and consumption of low- and no-alcohol beers and wines. Three papers indicated confusion amongst consumers with respect to the labelling of low- and no-alcohol products. One paper indicated that the introduction of a minimum unit price in both Scotland and Wales favoured shifts in purchases from higher- to lower-strength beers. The evidence base for the potential beneficial health impact of low- and no-alcohol products is very limited and needs considerable expansion. At present, the evidence base could be considered inadequate to inform policy.

Starmerella bombicola and Saccharomyces cerevisiae in Wine Sequential Fermentation in Aeration Condition: Evaluation of Ethanol Reduction and Analytical Profile

In the last few decades, the increase of ethanol in wine, due to global climate change and consumers’ choice is one of the main concerns in winemaking. One of the most promising approaches in reducing the ethanol content in wine is the use of non-Saccharomyces yeasts in co-fermentation or sequential fermentation with Saccharomyces cerevisiae. In this work, we evaluate the use of Starmerella bombicola and S. cerevisiae in sequential fermentation under aeration condition with the aim of reducing the ethanol content with valuable analytical profile. After a preliminary screening in synthetic grape juice, bench-top fermentation trials were conducted in natural grape juice by evaluating the aeration condition (20 mL/L/min during the first 72 h) on ethanol reduction and on the analytical profile of wines. The results showed that S. bombicola/S. cerevisiae sequential fermentation under aeration condition determined an ethanol reduction of 1.46% (v/v) compared with S. cerevisiae pure fermentation. Aeration condition did not negatively affect the analytical profile of sequential fermentation S. bombicola/S. cerevisiae particularly an overproduction of volatile acidity and ethyl acetate. On the other hand, these conditions strongly improved the production of glycerol and succinic acid that positively affect the structure and body of wine.

The Effect of Non-Saccharomyces and Saccharomyces Non-Cerevisiae Yeasts on Ethanol and Glycerol Levels in Wine

Non-Saccharomyces and Saccharomyces non-cerevisiae studies have increased in recent years due to an interest in uninoculated fermentations, consumer preferences, wine technology, and the effect of climate change on the chemical composition of grapes, juice, and wine. The use of these yeasts to reduce alcohol levels in wines has garnered the attention of researchers and winemakers alike. This review critically analyses recent studies concerning the impact of non-Saccharomyces and Saccharomyces non-cerevisiae on two important parameters in wine: ethanol and glycerol. The influence they have in sequential, co-fermentations, and solo fermentations on ethanol and glycerol content is examined. This review highlights the need for further studies concerning inoculum rates, aeration techniques (amount and flow rate), and the length of time before Saccharomyces cerevisiae sequential inoculation occurs. Challenges include the application of such sequential inoculations in commercial wineries during harvest time.

Copper(II) and Sulfur Dioxide in Chardonnay Juice and Shiraz Must: Impact on Volatile Aroma Compounds and Cu Forms in Wine

This work outlines the influence of Cu(II) and SO2 concentrations in Chardonnay juice or Shiraz must on the respective wine composition. Analyses were conducted pre- and post-fermentation, after cold stabilization, after bentonite treatment (Chardonnay only), at bottling, and 15 months after bottling. The quantification of total Cu was conducted by inductively coupled plasma optical emission spectrometry and free Cu by stripping potentiometry. Low molecular weight sulfur compounds, volatile aldehyde compounds, and general volatile compounds, including esters and terpenes, were quantified with gas-chromatography- or liquid-chromatography-QQQ-mass spectrometry. For Chardonnay, increased Cu concentration in the juice resulted in higher concentrations of Cu in the respective wine, while Shiraz wines showed no significant difference. Increased Cu addition to Chardonnay juice also produced significantly higher concentrations of H2S, 3-methylbutanal, and methional, but lower concentrations of methanethiol and phenylacetaldehyde, while SO2 addition increased 3-methylbutanal and phenylacetaldehyde, and decreased methanethiol production from post-fermentation to post-bottle aging. For the Shiraz, SO2 led to higher concentrations of H2S, and both SO2 and Cu addition increased the concentrations of hexanal, 3-methylbutanal, and phenylacetaldehyde in wine, but this effect diminished after cold stabilization. This study shows that SO2 and Cu in grape juice/must can have long-term implications for wine composition.

Application of yeast with reduced alcohol yield for sparkling wine production

Two commercial yeast strains with reduced alcohol production in comparison with a commercial yeast strain with common alcohol yield were assed for their suitability in sparkling wine production according to the traditional bottle fermentation. The different yeast strains were applied for the first fermentation. As expected the base wine differed in terms alcohol. Furthermore the yeast with lower alcohol content showed higher values of glycerol, higher arginine content and in the same time reduced levels of proline after fermentation. However those samples showed increased volatile acidity values, compared to the control wines. The later bottle fermentation with a uniform yeast strain showed similar fermentation kinetics for all four lots. Sensory evaluation showed no clear differences between the sparkling wines that were stored 9 months on the lees. The base wines nevertheless clearly differed from each other. Besides the increased production of volatile acidity, the tested yeast strains with lower alcohol production appear very promising for the sparkling wine industry to face the generally rising alcohol contents worldwide.

SPME Method Optimized by Box-Behnken Design for Impact Odorants in Reduced Alcohol Wines

The important sampling parameters of a headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure such as the extraction temperature, extraction time, and sample volume were optimized to quantify 23 important impact odorants in reduced alcohol red and white wines. A three-factor design of Box-Behnken experiments was used to determine the optimized sampling conditions for each analyte, and a global optimized condition at every ethanol concentration of interest determined using a desirability function that accounts for a low signal response for compounds. Shiraz and Chardonnay wines were dealcoholized from 13.7 and 12.2% v/v ethanol respectively, to 8 and 5% v/v, using a commercially available membrane-based technology. A sample set of the reduced alcohol wines were also reconstituted to their natural ethanol level to evaluate the effect of the ethanol content reduction on volatile composition. The three-factor Box-Behnken experiment ensured an accurate determination of the headspace concentration of each compound at each ethanol concentration, allowing comparisons between wines at varying ethanol levels to be made. Overall, the results showed that the main effect of extraction temperature was considered the most critical factor when studying the equilibrium of reduced alcohol wine impact odorants. The impact of ethanol reduction upon the concentration of volatile compounds clearly resulted in losses of impact odorants from the wines. The concentration of most analytes decreased with dealcoholization compared to that of the natural samples. Significant differences were also found between the reconstituted volatile composition and 5% v/v reduced alcohol wines, revealing that the dealcoholization effect is the result of a combination between the type of dealcoholization treatment and reduction in wine ethanol content.