Aromatic and Sensory Characterization of Maturana Blanca Wines Made with Different Technologies

Flavoromic analysis of wines using gas chromatography, mass spectrometry and sensory techniques

Various sensory perceptions drive the quality and typicality of wines, with the volatile profile playing a fundamental role in the characteristics of odor, aroma and consequently flavor, which combines the smell (odor and aroma), taste, and trigeminal sensations. Efforts have been made in both the field of instrumental and sensory analysis to understand the relationship of volatile compounds with sensory attributes in omics approaches. Gas chromatography (monodimensional and two-dimensional (heartcutting and comprehensive)) associated with mass spectrometry (GC/MS, GC-GC/MS and GCxGC/MS) and chemometric tools have contributed to foodomics analyses, specifically those linked to metabolomics/volatilomics. These tools, along with the elucidation of sensory properties (sensomics), lead to advanced results in the field of flavoromics. They also help to define the best practices in both vineyard management and winemaking that enable the production of high-quality wines. The objective of this review is to report the challenges of determining the volatile profile of wines, pointing out the ways that can be followed in successful identification and quantification of volatile compounds. The state of the art of sensory evaluation methods is also addressed, providing information that helps in choosing the most appropriate sensory method to be conducted with chromatographic analysis to achieve more in-depth results in the field of flavoromics.

White wine vinification and an expanded insight into pellicular macerations: bibliometric and bibliographic review

BACKGROUND

Pellicular macerations in the vinification of white wines involve the contact of grape skins and seeds with the must before, during or after alcoholic fermentation. Pre-fermentative pellicular maceration aims to enrich the must with volatile compounds and aroma precursors. Fermentative maceration occurs during alcoholic fermentation, whereas post-fermentative maceration is carried out after this process, associated with orange, amber or skin-contact wines, which have experienced a growing global demand in recent years. In this context, this research aimed to conduct a bibliometric review on pellicular macerations in white wines using two search strategies on the specific platform for the period from 2010 to 2023. Additionally, we sought to identify research trends in this segment of the wine industry through a comprehensive literature review of the retrieved documents.

RESULTS

The results emphasized more studies on pre-fermentative pellicular maceration than on long-duration macerations during and after alcoholic fermentation. Alternative maceration techniques, such as grape freezing, were also observed as study subjects, including their effects on final wines. The research identified a wide variety of grapes explored in studies related to pellicular macerations of the Vitis vinifera L. species, with approximately 50 distinct nomenclatures identified. Regarding pre-fermentative macerations, the contact time varied from 2 to 60 h, with the temperature range 1-20 °C.

CONCLUSION

The specific search for extended skin contact white wines revealed a limited number of available documents, indicating that studies related to this product style are promising and necessary, given the growing commercial relevance of this product profile. © 2024 Society of Chemical Industry.

Volatilomics of Fruit Wines

Volatilomics is a scientific field concerned with the evaluation of volatile compounds in the food matrix and methods for their identification. This review discusses the main groups of compounds that shape the aroma of wines, their origin, precursors, and selected metabolic pathways. The paper classifies fruit wines into several categories, including ciders and apple wines, cherry wines, plum wines, berry wines, citrus wines, and exotic wines. The following article discusses the characteristics of volatiles that shape the aroma of each group of wine and the concentrations at which they occur. It also discusses how the strain and species of yeast and lactic acid bacteria can influence the aroma of fruit wines. The article also covers techniques for evaluating the volatile compound profile of fruit wines, including modern analytical techniques.

Recent Advances and Future Perspectives in the E-Nose Technologies Addressed to the Wine Industry

Electronic nose devices stand out as pioneering innovations in contemporary technological research, addressing the arduous challenge of replicating the complex sense of smell found in humans. Currently, sensor instruments find application in a variety of fields, including environmental, (bio)medical, food, pharmaceutical, and materials production. Particularly the latter, has seen a significant increase in the adoption of technological tools to assess food quality, gradually supplanting human panelists and thus reshaping the entire quality control paradigm in the sector. This process is happening even more rapidly in the world of wine, where olfactory sensory analysis has always played a central role in attributing certain qualities to a wine. In this review, conducted using sources such as PubMed, Science Direct, and Web of Science, we examined papers published between January 2015 and January 2024. The aim was to explore prevailing trends in the use of human panels and sensory tools (such as the E-nose) in the wine industry. The focus was on the evaluation of wine quality attributes by paying specific attention to geographical origin, sensory defects, and monitoring of production trends. Analyzed results show that the application of E-nose-type sensors performs satisfactorily in that trajectory. Nevertheless, the integration of this type of analysis with more classical methods, such as the trained sensory panel test and with the application of destructive instrument volatile compound (VOC) detection (e.g., gas chromatography), still seems necessary to better explore and investigate the aromatic characteristics of wines.

Influence of Cold Pre-Fermentation Maceration on the Volatilomic Pattern and Aroma of White Wines

Aroma compounds play a key role in wine quality due to their importance in wine aroma. The aim of the present study is to investigate the influence of cold pre-fermentative maceration (CPM) treatment on aromatic and sensory properties of white wines from four grape varieties (Tempranillo Blanco, Maturana Blanca, Viura and Garnacha Blanca) during two consecutive years (2019 and 2020). A total of 62 aroma compounds belonging to different chemical families were identified using headspace solid-phase microextraction combined with gas chromatography mass spectrometry (HS-SPME/GC-MS). CPM treatment enhanced the total relative concentration of alcohols, esters and acids compared to control wines. Regarding sensorial properties, esters made the greatest contribution to the studied white wines, mainly through the development of floral and fruity notes. On the other hand, CPM treatment did not significantly influence the total relative concentration of terpenoids, and different trends were observed according to grape variety and vintage. The obtained results showed differences in the wine's aromatic complexity according to the grape variety, the vintage and the treatment applied and suggested that CPM treatment could represent a suitable approach to manipulate the aromatic profile and enhance the aromatic quality and complexity of wine.

Saturated Linear Aliphatic γ- and δ-Lactones in Wine: A Review

Saturated linear aliphatic lactones are widespread aroma compounds in wine, linked to stone fruit, dried red fruit, and coconut descriptors. Despite their ubiquity, bioproduction pathways associated with these compounds in wine are unclear, but higher concentrations have been linked to many common vitivinicultural practices, including grape variety, microbiological influence, oak- and bottle-aging, and wine styles such as late harvest, noble rot, and icewine. Development of analytical techniques has enabled increasingly accurate quantification of lactones in wine, shedding more light on their potential origins. This review provides an in-depth summary of the research into linear aliphatic lactones over the past 50 years and provides direction for possible future research to elucidate the biogenesis of these compounds and better estimate their impact on wine aroma.

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.

Effects from the Freezing of Either Whole or Crushed Grapes on the Volatile Compounds Contents in Muscat Wines

The transfer of aromatic compounds from the grape skins to the musts has been studied using a process involving freezing whole bunches or crushed grapes for winemaking the Muscat of Alexandria variety (white wine). Subsequently, a prefermentative maceration has been applied to some of the samples. The aromatic profiles of the final wines have been determined using gas chromatography coupled to mass spectrophotometry (GC-MS). The results revealed that, in the trials in which whole grapes were frozen, the final wines had a higher aromatic concentration compared to that of wines obtained by either freezing crushed grapes or obtained with traditional winemaking techniques. Thus, the wines produced from frozen whole grapes were found to exhibit different characteristics from the rest of the wines. The compounds affected by the freezing either of the whole bunches or the crushed grapes were terpenes, acids, and esters. Lower differences were found for wines produced applying prefermentative maceration after the freezing process.

Fast and Reliable Multiresidue Analysis of Aromas in Wine by Means of Gas Chromatography Coupled with Triple Quadrupole Mass Spectrometry

The paper would like to show a direct injection into GC-MS/QqQ for the determination of secondary aromas in white wine samples fermented in two different ways. The procedure has been compared with more traditional methods used in this field, i.e., headspace analysis and liquid–liquid extraction. The application of such direct injection, for the first time in the literature, allows us to analyze Volatile Organic Compounds (VOCs) in the range 0.1–100 µg mL−1, with Limits of Detection (LODs) and Limits of Quantification (LOQs) between 0.01–0.05 µg mL−1 and 0.03–0.09 µg mL−1, respectively, intraday and interday below 5.6% and 8.5%, respectively, and recoveries above 92% at two different fortification levels. The procedure has been applied to real wine samples: it evidences how the fermentation in wood (cherry) barrel yields higher VOC levels than ones in wine fermented in steel tank, causing production of different secondary aromas and different relative flavors.