Untangling the impact of red wine maceration times on wine ageing. A multidisciplinary approach focusing on extended maceration in Shiraz wines

Phenolic budget in red winemaking: Influence of maceration temperature and time

This study investigates the effects of maceration temperature (24 or 29 °C) and duration (12, 18, or 24 days) on phenolic compounds during 'Nebbiolo' wine-like extraction and lab-scale winemaking. In wine-like maceration, anthocyanins quickly peaked and then decreased, with temperature alone showing limited influence on extraction or degradation. In lab-scale fermentations, the rapid anthocyanin extraction at 29 °C was followed by higher degradation, driven by fermentative enzymatic activities and evidenced by increased skin softening at higher temperatures. Longer macerations led to less wine anthocyanins. Tri-substituted anthocyanins were better preserved at 24 °C. Tannin content and structure were minimally affected. Phenolic analyses of grapes, wine, pomace, and lees revealed the extracted, unextracted, resorbed, and degraded phenolic fractions. Reduced anthocyanins in pomace at higher temperatures or extended maceration indicated enhanced extraction and subsequent degradation. The study introduces a "phenolic budget" concept, highlighting the interplay of maceration parameters shaping 'Nebbiolo' wine phenolics.

How Does Extended Maceration Affect Tannin and Color of Red Wines from Cold-Hardy Grape Cultivars?

Red wines produced with interspecific grape cultivars tend to have low tannin concentration and are therefore unbalanced. Extended maceration (EM) is a common winemaking technique which can promote the extraction of tannins from grape skins and seeds. The goal of this study was to evaluate the effect of EM on the tannin concentration, color intensity and other chemical properties of red wines made from cold-hardy grape cultivars. The wines were made from two cold-hardy interspecific grape cultivars (Marquette, and Petite Pearl) for either 7 days (control) or 21 days (EM) before pressing. Chemical analysis of the wines was conducted to determine their tannin concentration and color parameters at different stages of the process and after 14 months of aging. EM resulted in an improvement in the iron-reactive phenolic content of Marquette red wines (from 582 to 969 mg/L at bottling in control and EM wines, respectively), but no significant improvement in tannin content. The hue of Petite Pearl wines increased following EM only at pressing, and color intensity of those wines decreased at pressing and bottling by 43% and 52%, respectively. This study was the first one conducted on non-Vitis vinifera grapes which showed a lack of impact of EM on the phenolics and tannin concentration in the red wines made in 2022.

The composition and structure of plant fibers affect their fining performance in wines

In recent years, the wine industry has shifted towards plant-based fining agents for food safety reasons and consumer preferences. This study analysed the interaction of five plant fibers with red wine phenolic compounds to determinate their performance as fining agents. Chemical composition, polysaccharide profile, and physical properties were examined. Pea, cellulose, and Sauvignon Blanc pomace fibers effectively reduced tannin content while minimally affecting the concentration of anthocyanins, flavonols and wine color. Contrary to previous beliefs, the presence of pectins in fibers didn't play a crucial role in phenolic compound interaction since cellulose-rich fibers with low pectin concentration also bound tannins effectively, especially those with small particle size and high contact surface. Pea fiber, rich in cellulose and pectins, showed remarkable tannin retention while minimally affecting wine color. This research highlights the potential of plant fibers as effective fining agents in wine production and how their composition affects their performance.

Mouthfeel subqualities in wines: A current insight on sensory descriptors and physical-chemical markers

Astringency and more generally mouthfeel perception are relevant to the overall quality of the wine. However, their origin and description are still uncertain and are constantly updating. Additionally, the terminology related to mouthfeel properties is expansive and extremely diversified, characterized by common traditional terms as well as novel recently adopted descriptors. In this context, this review evaluated the mention frequency of astringent subqualities and other mouthfeel attributes in the scientific literature of the last decades (2000-August 17, 2022). One hundred and twenty-five scientific publications have been selected and classified based on wine typology, aim, and instrumental-sensorial methods adopted. Dry resulted as the most frequent astringent subquality (10% for red wines, 8.6% for white wines), while body-and related terms-is a common mouthfeel sensation for different wine types, although its concept is still vague. Alongside, promising analytical and instrumental techniques investigating and simulating the in-mouth properties are discussed in detail, such as rheology for the viscosity and tribology for the lubrication loss, as well as the different approaches for the quantitative and qualitative evaluation of the interaction between salivary proteins and astringency markers. A focus on the phenolic compounds involved in the tactile perception was conducted, with tannins being the compounds conventionally found responsible for astringency. Nevertheless, other non-tannic polyphenolic classes (i.e., flavonols, phenolic acids, anthocyanins, anthocyanin-derivative pigments) as well as chemical-physical factors and the wine matrix (i.e., polysaccharides, mannoproteins, ethanol, glycerol, and pH) can also contribute to the wine in-mouth sensory profile. An overview of mouthfeel perception, factors involved, and its vocabulary is useful for enologists and consumers.

SPME-GC-MS combined with chemometrics to assess the impact of fermentation time on the components, flavor, and function of Laoxianghuang

Laoxianghuang, fermented from Citrus medica L. var. Sarcodactylis Swingle of the Rutaceae family, is a medicinal food. The volatiles of Laoxianghuang fermented in different years were obtained by solid-phase microextraction combined with gas chromatography–mass spectrometry (SPME-GC–MS). Meanwhile, the evolution of its component-flavor function during the fermentation process was explored in depth by combining chemometrics and performance analyses. To extract the volatile compounds from Laoxianghuang, the fiber coating, extraction time, and desorption temperature were optimized in terms of the number and area of peaks. A polydimethylsiloxane/divinylbenzene (PDMS/DVB) with a thickness of 65 μm fiber, extraction time of 30 min, and desorption temperature of 200 °C were shown to be the optimal conditions. There were 42, 44, 52, 53, 53, and 52 volatiles identified in the 3rd, 5th, 8th, 10th, 15th, and 20th years of fermentation of Laoxianghuang, respectively. The relative contents were 97.87%, 98.50%, 98.77%, 98.85%, 99.08%, and 98.36%, respectively. Terpenes (mainly limonene, γ-terpinene and cymene) displayed the highest relative content and were positively correlated with the year of fermentation, followed by alcohols (mainly α-terpineol, β-terpinenol, and γ-terpineol), ketones (mainly cyclohexanone, D(+)-carvone and β-ionone), aldehydes (2-furaldehyde, 5-methylfurfural, and 1-nonanal), phenols (thymol, chlorothymol, and eugenol), esters (bornyl formate, citronellyl acetate, and neryl acetate), and ethers (n-octyl ether and anethole). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed a closer relationship between the composition of Laoxianghuang with similar fermentation years of the same gradient (3rd-5th, 8th-10th, and 15th-20th). Partial least squares discriminant analysis (PLS-DA) VIP scores and PCA-biplot showed that α-terpineol, γ-terpinene, cymene, and limonene were the differential candidate biomarkers. Flavor analysis revealed that Laoxianghuang exhibited wood odor from the 3rd to the 10th year of fermentation, while herb odor appeared in the 15th and the 20th year. This study analyzed the changing pattern of the flavor and function of Laoxianghuang through the evolution of the composition, which provided a theoretical basis for further research on subsequent fermentation.

Effect of the cold pre-fermentative maceration and aging on lees times on the phenolic compound profile, antioxidant capacity and color of red sparkling wines

This was the first study evaluating the impact of cold pre-fermentative maceration using refrigeration on the nutraceutical quality and color of red sparkling wines elaborated with the cultivar Syrah, and the evolution of these variables with different autolysis times. The sparkling wines were elaborated using the traditional method with different maceration times (NM, 24 and 72 h) and aging on lees (3 and 18 months of autolysis). In the sequence, it was conducted the characterization of the phenolic compound profile by HPLC-DAD (n = 21), the antioxidant capacity (ABTS, DPPH, and FRAP assays), and the color (CIELab and CIEL*C*h systems). The total phenolic content (TPC) and antioxidant capacity (AOX) were higher with longer maceration (M72) and autolysis (18 months) times, reaching 453.54 mg L-1 of TPC, and AOX above 2.11 mmol TEAC L-1 by the three in vitro assays conducted. Cis-resveratrol, kaempferol-3-O-glucoside, quercetin-3-β-d-glucoside, isorhamnetin-3-O-glucoside, and petunidin-3-O-glucoside showed a good correlation (r > 0.8; P < 0.05) with the antioxidant capacity and were found in higher concentrations in the sparkling wines elaborated with maceration. In addition, maceration promoted a more intense red (a*) and saturated (C*) color. Thus, the results indicated that cold pre-fermentative maceration and autolysis positively influenced the bioactive potential and the color of the red sparkling wines. This practice should be better explored through the elaboration of this product.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05531-z.