Wine Color Research Articles

Effects of Seven Sterilization Methods on the Functional Characteristics and Color of Yan 73 (Vitis vinifera) Grape Juice.

Yan 73 (Vitis vinifera) is a dyed grape variety cultivated in China. Currently, most studies have focused on the mechanism of anthocyanins or the impact of anthocyanins as auxiliary color varieties on wine color. There is little research on its direct use or direct processing of products such as juice. In order to investigate the effects of different processing methods on the juice of Yan 73 grapes, the physicochemical and functional properties, as well as the sensory indexes of the juice, were analyzed by using thermal pasteurization (TP), thermosonication (TS), TS combined with nisin (TSN), TS combined with ε-Polylysine (TSε), irradiation (IR), and high hydrostatic pressure (HHP). The physicochemical indexes, functional properties, and sensory indexes of Smoke 73 grape juice were determined and analyzed. The results of the study showed that among the seven sterilization methods, total polyphenol content (TPC) in juice was significantly increased in all treatments except HHP. TPC was the highest in TP (3773.33 mg GAE/L). Total anthocyanin content (TAC) was increased except IR5, and TSN (1202.67 mg/L) had the highest TAC. In terms of color, TP (a* = 36.57, b* = 19.70, L* = 14.81, C* = 41.55, h° = 28.30, ΔE = 5.9) promotes the dissolution of anthocyanins because of high temperatures, which basically improves all the color indicators of grape juice and makes the color of grape juice more vivid. After HHP treatment, the color (ΔE = 1.72) and aroma indicators are closer to the grape juice itself. The Entropy weight-TOPSIS, CRITIC-Topsis, and PCA integrated quality evaluation models showed that all selected TP as the best integrated quality.

Combined ultrasound and low temperature pretreatment improve the content of anthocyanins, phenols and volatile substance of Merlot red wine

Ultrasound combined with low temperature treatment is a new food processing technology. In this study, low temperature, three ultrasound power levels, and their combinations were adopted in the must before fermentation to study their effects on Merlot red wine. The results showed that ultrasound combined with low temperature pretreatment increased the total and monomer contents of anthocyanins and phenols, affected the color of the wine, and significantly increased its antioxidant capacity. In particular, 240 W of ultrasound combined with low temperature pretreatment reduced the bad odors (caprylic acid, benzaldehyde, and 1-ethanol content) and improved the flower and fruit aroma (1-octanol and phenethyl acetate), as well as the aftertaste, thus improving the quality of the wine. Ultrasound combined with low temperature pretreatment positively affected the quality of Merlot red wine.

Chemical and colorimetric study of the influence of grape soluble polysaccharides on the color and stability of malvidin 3-O-glucoside solutions

Red wine color is mainly due to anthocyanins’ flavylium cation. In wine, these pigments are involved in a pH-dependent equilibrium involving other forms, both colored and non-colored. This equilibrium is affected by the presence of other phenolic compounds, the so-called copigments. Moreover, other non-phenolic compounds that can be found in wine, such as polysaccharides, can also affect wine color. In this work, molecular dynamics simulations, tristimulus colorimetry and HPLC-DAD analyses have been performed to assess the effect of soluble polysaccharides (P) on the color and stability of malvidin 3-O-glucoside (Mv) solutions at different pH values, both in presence and absence of other compounds that can establish copigmentation interactions with the pigment. Results showed that P shifts the color of flavylium solutions towards a more intense color with bluer hues, which can be related to a stabilization of the blue quinoidal forms of anthocyanins. This effect is similar to that observed for quercetin 3-β-glucopyranoside (QG), although, in the case of P, it seems to be more relevant. This behavior could be due to the presence of hydrophobic regions in P that allows the interaction with the quinoidal forms, which in the case of the polysaccharide might be related to the type I rhamnogalacturonans.

Exploring the influence of S. cerevisiae mannoproteins on wine astringency and color: Impact of their polysaccharide part.

The impact of the polysaccharide moiety of mannoproteins (MPs) on the color and astringency of red wines was studied respectively through spectrophotometry and their impact on tannin interactions with BSA. To this end, MPs with conserved native structures from four different Saccharomyces cerevisiae strains were used: a Wild-Type strain (BY4742, WT) taken as reference, mutants ΔMnn4 (with no mannosyl-phosphorylation) and ΔMnn2 (linear N-glycosylation backbone), and a commercial enological strain. MPs affected tannin-BSA interactions by delaying aggregation kinetics. To achieve it, a well-balanced density/compactness of the polysaccharide moiety of MPs was a key factor. MP-WT and MP-Mnn2 acted as weak copigments and induced a slight increase in the absorbance of Malvidin-3-O-Glucoside. The same MPs also promoted a synergistic effect during the copigmentation of Quercetin-3-O-Glucoside with Malvidin-3-O-Glucoside. The intensity of these hyperchromic effects was related to the accessibility of anthocyanins to negatively charged mannosyl-phosphate groups within the polysaccharide moiety.

The key role of vineyard parcel in shaping flavonoid profiles and color characteristics of Cabernet Sauvignon wines combined with the influence of harvest ripeness, vintage and bottle aging.

Recently, revealing the terroir influence on wine chemical features has drawn increasing interest. This study aimed to explain how wine flavonoid signatures were altered by vineyard parcel, harvest ripeness, vintage and bottle aging. Six commercial Cabernet Sauvignon vineyards were selected in the Manas region to produce wines at three harvest ripeness in three seasons (2019-2021) and aged for three years. The six vineyards had little difference in mesoclimate conditions while varying greatly in soil composition. Results showed high vineyard pH (> 8.5) could accelerate grape ripening rate and increase wine flavonol concentration. Vineyards with moderate nutrition produced wines with abundant anthocyanin derivatives and maintained color characteristics during aging. The role of detailed anthocyanin derivatives in regulating wine color was clarified. As the harvest ripeness elevated, wine's flavonoid profiles were altered and gained a higher red color intensity. This work provides chemical mechanisms underlying single-vineyard wines and a theoretical basis for targeted wine production.

Comprehensive Evaluation of Ten Actinidia arguta Wines Based on Color, Organic Acids, Volatile Compounds, and Quantitative Descriptive Analysis.

Actinidia arguta wine is a low-alcoholic beverage brewed from A. arguta with a unique flavor and sweet taste. In this study, the basic physicochemical indicators, color, organic acid, and volatile aroma components of wines made from the A. arguta varieties 'Kuilv', 'Fenglv', 'Jialv', 'Wanlv', 'Xinlv', 'Pinglv', 'Lvbao', 'Cuiyu', 'Tianxinbao', and 'Longcheng No.2' were determined, and a sensory evaluation was performed. The findings show that 'Tianxinbao' produced the driest extract (49.59 g/L), 'Kuilv' produced the most Vitamin C (913.46 mg/L) and total phenols (816.10 mg/L), 'Jialv' produced the most total flavonoids (477.12 mg/L), and 'Cuiyu' produced the most tannins (4.63 g/L). We analyzed the color of the A. arguta wines based on CIEL*a*b* parameters and found that the 'Kuilv' and 'Longcheng No.2' wines had the largest L* value (31.65), the 'Pinglv' wines had the greatest a* value (2.88), and the 'Kuilv' wines had the largest b* value (5.08) and C*ab value (5.66) of the ten samples. A total of eight organic acids were tested in ten samples via high-performance liquid chromatography (HPLC), and we found that there were marked differences in the organic acid contents in different samples (p < 0.05). The main organic acids were citric acid, quinic acid, and malic acid. The aroma description of a wine is one of the keys to its quality. A total of 51 volatile compounds were identified and characterized in ten samples with headspace gas chromatography-ion mobility spectrometry, including 24 esters, 12 alcohols, 9 aldehydes, 3 aldehydes, 2 terpenes, and 1 acid, with the highest total volatile compound content in 'Fenglv'. There were no significant differences in the types of volatile compounds, but there were significant differences in the contents (p < 0.05). An orthogonal partial least squares discriminant analysis (OPLS-DA) based on the odor activity value (OAV) showed that ethyl butanoate, ethyl pentanoate, ethyl crotonate, ethyl isobutyrate, butyl butanoate, 2-methylbutanal, ethyl isovalerate, and ethyl hexanoate were the main odorant markers responsible for flavor differences between all the A. arguta wines. Sensory evaluation is the most subjective and effective way for consumers to judge A. arguta wine quality. A quantitative descriptive analysis (QDA) of the aroma profiles of ten grapes revealed that the 'fruity' and 'floral' descriptors are the main and most essential parts of the overall flavor of A. arguta wines. 'Tianxinbao' had the highest total aroma score. The flavor and quality of A. arguta wines greatly depend on the type and quality of the A. arguta raw material. Therefore, high-quality raw materials can improve the quality of A. arguta wines. The results of the study provide a theoretical basis for improving the quality of A. arguta wines and demonstrate the application prospects of HS-GC-IMS in detecting A. arguta wine flavors.

Sequential inoculation of flocculent Torulaspora delbrueckii with Saccharomyces cerevisiae increases color density of Pinot Noir wines.

Pinot noir grapes require careful management in the winery to prevent loss of color density and promote aging stability. Winemaking with flocculent yeast has been shown to increase color density, which is desirable to consumers. This research explored interspecies sequential inoculation and co-flocculation of commercial yeast on Pinot noir wine color. Sedimentation rates of six non-Saccharomyces species and two Saccharomyces cerevisiae strains were assayed individually and in combination. The most flocculent pairings, Torulaspora delbrueckii BIODIVA with S. cerevisiae RC212 or VL3, were used to ferment 20 L Pinot noir must. Sequential fermentations produced wines with greater color density at 420 + 520 nm, confirmed by sensory panel. Total and monomeric anthocyanin concentrations were decreased in sequentially fermented wines, despite being the main source of red wine color. BIODIVA adsorbed more anthocyanins than S. cerevisiae, indicating a greater number of cell wall mannoproteins in flocculent yeast, that could then result in a later release of anthocyanins and enhance copigment formation in red wines.

Effects of Main Nutrient Sources on Improving Monascus Pigments and Saccharifying Power of Monascus purpureus in Submerged Fermentation

Hong Qu (HQ), obtained through fermentation of various grains using Monascus spp., has been widely utilized as the main and characteristic initial saccharification and traditional fermentation starter in the food brewing industry. The quality, color, and flavor of HQ and HQ wine are closely related to the saccharifying power (SP) and Monascus pigments (MPs) of Monascus spp. In this study, to optimize the culture medium in submerged fermentation by M. purpureus G11 for improving SP and MPs, the effects of carbon source, nitrogen source, inorganic salts, and vitamins on SP activity and biosynthesis of MPs were explored through single-factor analysis and response surface Box–Behnken experiments. The results showed that the optimal medium composition was 6.008% rice powder, 1.021% peptone, 0.0049% CuSO4, and 0.052% vitamin B1. Validation experiments performed under the optimized fermentation conditions showed a significant increase in MPs and SP by 14.91% and 36.24%, with maximum MPs and SP reaching 112.61 and 365.12 u/mL, respectively. This study provides a theoretical basis for enhancing MPs and SP in M. purpureus for HQ production, to improve the production efficiency and shorten the production cycle of HQ-related fermentation products.

Wine Grapes Ripening: A Review on Climate Effect and Analytical Approach to Increase Wine Quality

Red wine grapes have an important impact on the economy of many regions, both for wine quality and for their richness in phenolic compounds, which have many health benefits. Climate has been changing substantially in the last years, which affects greatly grape polyphenolic composition and wine quality. In this review, we will unveil the importance of climate in grape development, both physically and chemically, the different methodologies used to evaluate grape quality, the interesting new approaches using NIR spectroscopy, and the functional properties of grapes and red wine, due to their high phenolic content. Climate has an impact in the development of phenolic compounds in grapes, namely in the anthocyanins biosynthesis. The phenolic chemical composition changes during maturation, therefore, it is essential to keep on track the accumulation of these key compounds. This information is crucial to help producers choose the best harvest date since specific compounds like polyphenols are responsible for the color, taste, and mouthfeel of wines, which directly affects wine quality. The usage of different methodologies to assess quality parameters in grapes and wine, can be used to provide essential information to create the chemical profile of each variety to develop calibration methods. NIR spectroscopy seems to be a reliable method to be used in vineyards during grape maturation to provide real time information on quality parameters to producers since many reliable calibration models have been developed over time.

Il mare color del vino

The article offers a phenomenological reflection on Homer’s image of the sea being the colour of wine. Indeed, this image refers to its deep imaginative connection with blood and life, with the earth and death.

PHYSICOCHEMICAL EVALUATION OF THE GRAPE AND WINE OF THE BLATINA, TRNJAK AND VRANAC IN DIFFERENT VINTAGES

Typicality and style of wine are closely related to the varietal character of grapes, ecological properties of the locality, and the specificities of the winemaking process. For this reason, autochthonous and indigenous grape varieties are increasingly the subject of many studies. To protect their uniqueness, in the region of Hercegovina (Bosnia and Herzegovina), indigenous grape varieties are part of the current grape and wine production. Therefore, the subject of a two-year study (2018-2019) were indigenous wine varieties: Blatina, Trnjak, and Vranac. Variations in the values of the analyzed parameters were a consequence of the significant and/or highly significant influence of the variety and year. Blatina stood out from other varieties with the highest average cluster weight (364.90 g) and the highest wine color intensity (10.71). Trnjak had the highest total anthocyanin content in the grape skin and total polyphenol content in the grape seeds (1090.198 mg/kg grapes; 1755.195 mg/kg grapes), while Vranac had the highest polyphenol content in the grape skin (1823.961 mg/kg grapes), the highest TSS level (21.55% Brix), and consequently, the highest alcohol content in the wine (12.07% v/v).

The Marketing of Experiences in the Wine Industry in Romania

Today, many companies have turned their attention from the traditional "features and benefits" to the activity of creating experiences for their customers. In this way, the emotional activation of the customer is attempted, in addition to the rational part of buying the product. As part of this work, we have carried out quantitative marketing research, to find out the opinions of Romanian consumers related to the wine consumption experience. The general objectives of the research are the following: identify consumption habits among Romanian wine consumers; identify how Romanian consumers prefer to enjoy their favorite wine; determine the preferences of Romanian consumers regarding the color and type of preferred wine; determine the frequency of the purchase of wine by Romanian consumers and the place where they purchase their preferred types of wine. The research results can address wine-producing companies from Romania, wine distributors, hotels, and restaurants, for the future development of activities in this field.

Color Characterization of Bordeaux Red Wines Produced without Added Sulfites.

Nowadays, the development of naturalness as a concept is illustrated in the oenological field by the development of wine produced with lower inputs, sometimes even without any addition of SO2 throughout the winemaking process, up to the bottling stage. Despite the increase in the offer of these wines, they remain poorly explored in the literature and require characterization. This study was developed to evaluate the color of Bordeaux red wines without SO2 addition using colorimetric and polymeric pigments analysis. From a batch of commercial Bordeaux red wines with and without SO2 addition, and experimental wines produced from homogenous grapes according to different winemaking processes, colorimetric analyses (CIELab and color intensity (CI)) revealed a large difference in wine color depending on the presence or absence of SO2. Indeed, wines without SO2 were significantly darker and presented with a deeper purplish color. According to these observations, polymeric pigments were quantified using UPLC-DAD/ESI QTof, and a higher concentration of polymeric pigments bound by the ethylidene bridge was observed in wines without SO2. This correlated with differences observed for CIELab and CI. Finally, a comparison with polymeric tannins bound by ethylidene bridge was made and revealed that no differences were observed between wines with and without added SO2. This underlines the affinity difference between tannins and anthocyanins to react with acetaldehyde to form ethylidene bridges.

The flavour of grape colour: anthocyanin content tunes aroma precursor composition by altering the berry microenvironment.

Anthocyanin-less (white) instead of black/red (coloured) fruits develop in grapevine cultivars without functional VviMYBA1 and VviMYBA2 genes, which conditions the colour of wines that can be produced. To evaluate whether this genetic variation has additional consequences on fruit ripening and composition, we performed microenvironment, transcriptomics and metabolomics comparisons of developing grapes between near-isogenic white- and black-berried somatic variants of Garnacha and Tempranillo cultivars. Berry temperature was up to 3.5ºC lower in white- compared to black-berried Tempranillo. An RNA-seq study combined with targeted and untargeted metabolomics revealed that ripening fruits of white-berried variants were characterized by the upregulation of photosynthesis and other light-responsive genes and their higher accumulation of specific terpene aroma precursors, fatty acid-derived aldehyde volatiles and phenylpropanoid precursor amino acids. MYBA1-MYBA2 function proved essential for flavonol trihydroxylation in black-berried somatic variants, which were also characterized by enhanced pathogen defence gene expression in berry skin and increased accumulation of C6-derived alcohol and ester volatiles and GABA. Collectively, our results indicate that anthocyanin depletion entails side effects on grape composition by altering the berry internal microenvironment and the partition of the phenylpropanoid pathway. These findings show how fruit colour can condition other fruit features, such as flavour potential and stress homeostasis.

A New Approach for Quantitative Classification of Red Wine Color from the Perspective of Micro and Macro Levels

The classification of color is important in the management and evaluation of red wine color. Nevertheless, current reports have not given a sound solution. A novel scheme for the quantitative classification of red wine color from the perspective of micro and macro levels was proposed in this work. The overall color performance of 119 representative red wine samples was visualized and classified into 125 micro-classifications according to the partition of the chromaticity and lightness of the wine color. Considering the evolution of red wine color, quantitative macro-classification of the color of the wine samples was explored, and six macro-classifications were obtained. These few classifications determine the extent of aging and aging potential of colors between different red wines well. The performance of this approach was further verified by another set of 56 red wine samples. This efficient and easy-to-implement approach is expected to be helpful in the digital and visual color management, control, evaluation, comparison, and prediction of red wines.

New Insights into Wine Color Analysis: A Comparison of Analytical Methods to Sensory Perception for Red and White Varietal Wines.

The Glories method and CIE L*a*b* color space are poorly correlated in the light red high-saturation color area. Non-uniformities in the CIE L*a*b* color space have led to the CIEDE2000 formula, while the Euclidean color distance is still used in wine research. In this study, 112 white and red wines were examined to compare the Glories method, CIE L*a*b, and human perception using monovarietal wines from different grape varieties. The objective of this study was to investigate which of the two methods and which parameter of each method better aligned with human perception. The visual color threshold was re-evaluated with the CIEDE2000 formula and triangle testing. CIE L*a*b* more closely matched the human perception, elevating the use of CIE L*a*b* over the use of the Glories method. Visual color thresholds were better expressed with CIEDE2000 but still varied depending upon the color area in the CIE L*a*b* color space.

Yeast mannoproteins: Organoleptic modulating functions, mechanisms, and product development trends in winemaking

AbstractMannoproteins (MPs) originate from yeast cells and can play important roles in maintaining wine stability and modulating wine organoleptic properties. Due to their natural presence in wines, MP products are allowed to be used as enological additives in wine industry. To guarantee an appropriate application of these products during winemaking, it is necessary for both researchers and winemakers to understand the mechanisms of MPs as multifunctional organoleptic modulators. This review has introduced the current state of knowledge of the researches focus on the application of different MP products in red wines and also the interactions between MPs and wine sensory active components (polyphenols, aroma compounds) in model wine solutions. We have summarized the possible mechanisms of MPs that affect the color, astringency, and aroma of red wines and the relationship between the physicochemical characteristics and functionalities of MPs. Besides, development trends of MP products are also discussed. It seems that yeast biomass, especially those from non‐Saccharomyces yeasts show good potential in producing large quantities of MPs, an appropriate combination of yeast cultivation and preservation methods with extraction and purification techniques may obtain MPs of ideal production, purity, and functionality in an industrial scale, which should be put more efforts by both scientists and manufacturers in the future.

Effects of high power pulsed microwave on the enhanced color and flavor of aged blueberry wine.

A new method of high-power pulsed microwave (HPPM) was applied to accelerate the aging of blueberry wine. The color changes of blueberry wines during aging were investigated through Chemical Wine Age and CIE-LAB measurement. Results showed that the blueberry wines treated by HPPM at low frequencies (50 and 100Hz) exhibited improved color characteristics with L* value reaching 47.04 at 100Hz, an increased maturity of wine body, and a shortened chemical wine age from 90 days to 75 days. Moreover, the aroma changes determined by GC-MS showed that HPPM accelerated the formation of esters in blueberry wine, which were increased by 18.44% and 56.97% respectively under the conditions of 50 and 150Hz. The formation of acid substances was reduced compared with the original wine, with contents of acetic acid, caproic acid, and octanoic acid of 29.46µg/mL, 15.60µg/mL, 17.74µg/mL, respectively, displaying an enhanced wine flavor.

Forcing vine regrowth under different irrigation strategies: effect on polyphenolic composition and chromatic characteristics of cv. Tempranillo wines grown in a semiarid climate.

One of the effects of climate change in warm areas is the asynchrony between the dates of the technological and the phenolic maturity of grapes. This is important because the quality and color stability of red wines are directly related to the content and distribution of phenolic compounds. A novel alternative that has been proposed to delay grape ripening and make it coincide with a seasonal period more favorable for the formation of phenolic compounds is crop forcing. This consists of severe green pruning after flowering, when the buds of the following year have already differentiated. In this way, the buds formed during the same season are forced to sprout, initiating a new delayed cycle. The aim of the present work is to study the effect on the phenolic composition and color of wines elaborated from vines fully irrigated (C), grown using conventional non-forcing (NF) and forcing (F) techniques (C-NF and C-F), and wines from vines subjected to regulated irrigation (RI), grown using NF and F techniques (RI-NF and RI-F). The trial was carried out in an experimental vineyard of the Tempranillo variety located in a semi-arid area (Badajoz, Spain) in the 2017-2019 seasons. The wines (four by treatment) were elaborated and stabilized according to the classic methodologies for red wine. All wines had the same alcohol content, and malolactic fermentation was not carried out in any of them. Anthocyanin profiles were analyzed by HPLC, and total polyphenolic content, anthocyanin content, catechin content, the contribution to color due to co-pigmented anthocyanins, and various chromatic parameters were also determined. Although a significant effect of year was found for almost all the parameters analyzed, a general increasing trend in F wines was found for most of them. The anthocyanin profile of F wines was found to differ from that of C wines, especially in delphinidin, cyanidin, petunidin, and peonidin content. These results indicate that by using the forcing technique it was possible to increase the polyphenolic content by ensuring that the synthesis and accumulation of these substances occurred at more suitable temperatures.

Functional, antioxidant, and sensory properties of mixed-fruit (pitaya, watermelon, and mint) and pitaya wines.

Fermentation of fruits offers a diverse range of flavors, smells, and colors. Colored fruits are rich in naturally occurring pigments, such as betacyanin. Hence, they are considered to possess powerful antioxidant activities. However, in wine production, such pigments often diversify the flavor and color of the wine. The objective of this study was to compare the quality of two types of wines: a single-fruit (pitaya) wine and a mixed-fruit wine that contains watermelon (Citrullus lanatus), mint (Mintha spicata), and pitaya (Hylocereus costaricensis). In this study, fresh pitaya, watermelon, and mint leaves were fermented using Saccharomyces cerevisiae. Juice extracts underwent fermentation at room temperature for 7 days under dark conditions. Physicochemical changes, such as pH, sugar content, specific gravity, and alcohol content, were observed daily. The antioxidant activities were measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the ferric reducing antioxidant power (FRAP) assay, and total phenolic contents (TPCs). After 14 days of fermentation, the alcohol contents of mixed and pitaya wine were 11.22% (v/v) and 11.25%, respectively. The total sugar content of the mixed wine was 8.0 °Brix, while that of pitaya wine was 7.0 °Brix. Moreover, pitaya wine exhibited a higher TPC (22.7 mg GAE/100 g D.W.), and better FRAP (3578 μmole/L) and DPPH scavenging ability (80.2%) compared to the mixed wine with a TPC of 21.4 mg GAE/100 g D.W., FRAP of 2528 μmole/L, and DPPH of 75.6%., while the addition of watermelon and mint did not change the alcohol percentage contents of wine.