Relationship between Sensory Perception,Volatile and Phenolic Components in Commercial Spanish Red Wines from Different Regions

Polyphenols are an important fraction of the non-volatile components in the red wine matrix, and they are influenced in quantity and composition at all stages from the grape growing conditions until the time the wine is consumed. Evidence of their interaction with volatiles has been found, and this should affect wine flavour. A range of 12 commercial Spanish red wines from different regions and ages was analysed for their sensory properties, volatile composition in solution and headspace, and their non-volatile phenolic components. Maturation was the most important effect on sensory perception, while the chemical data showed also individual differences between the wines and their regions of production. Headspace volatiles and the phenolic fraction showed better correlations with the sensory perception, but volatiles in solution did not give a good prediction, though there were changes related to maturation. Some flavour components showed changes in their volatile behaviour in the matured wines. This supports the hypothesis that changes in the behaviour of the volatile fraction are related to the evolution of phenolic compounds.     

Differentiation of Wines Treated with Wood Chips Based on Their Phenolic Content,Volatile Composition,and Sensory Parameters

The effects of both wood chips addition and contact time on phenolic content, volatile composition, color parameters, and organoleptic character of red wine made by a native Greek variety (Agiorgitiko) were evaluated. For this purpose, chips from American, French, Slavonia oak, and Acacia were added in the wine after fermentation. A mixture consisting of 50% French and 50% Americal oak chips was also evaluated. In an attempt to categorize wine samples, various chemical parameters of wines and sensory parameters were studied after 1, 2, and 3 mo of contact time with chips. The results showed that regardless of the type of wood chips added in the wines, it was possible to differentiate the samples according to the contact time based on their phenolic composition and color parameters. In addition, wood‐extracted volatile compounds seem to be the critical parameter that could separate the samples according to the wood type. The wines that were in contact with Acacia and Slavonia chips could be separated from the rest mainly due to their distinct sensory characters.     

Volatile Composition of Macedonian and Hungarian Wines Assessed by GC/MS

The volatile composition of eight varietal wines Vranec, Merlot, Cabernet Sauvignon, Temjanika and Chardonnay from the Republic of Macedonia, and Portugieser, Kékfrankos and Tokaji Aszú from Hungary has been characterized by means of gas chromatography/mass spectrometry technique. The wine volatile compounds were extracted in dichloromethane, and the extracts were concentrated under nitrogen. Forty-four volatile compounds have been identified mainly using the NIST mass spectral library and by comparison with the available standards used for quantification as well. Differences between the wines were noted for a number of compounds, such as a higher concentration of 1-pentanol and 2-phenyl ethanol in the red wines. Monoterpenes, linalool and terpineol were detected only in the white wines, Chardonnay and Tokaji. Macedonian red wines were characterized by a higher level of alcohols, while the Hungarian wines contained a higher amount of esters, fatty acids and lactones. A statistical treatment including one-way ANOVA, followed by a Tukey’s test has been performed in order to ascertain possible significant differences between the wines studied, and principal component analysis to study the possible grouping of the wines.     

Effect of Process Parameters on Partial Dealcoholization of Wine by Osmotic Distillation

The effectiveness of the osmotic distillation process for partial dealcoholization of wine was investigated in this work. The dealcoholization process was performed using a hollow fibre membrane module and process parameters, such as hydrodynamic conditions, number of cycles, temperature and ethanol content of feed solution were investigated. Then the partial dealcoholization of Aglianico red wine was carried out up to 2 %vol and the chemicophysical properties evaluated and compared with the initial wine. No significant differences (p?<?0.05) in total volatile acidity, colour, total polyphenols and organic acids content, between Aglianico and dealcoholized wine were found. Empirical correlations available in the literature for calculation of ethanol mass transfer coefficient seems able to describe with reasonable agreement the effect of operating conditions of the dealcoholization process.     

Fining of Red Wines with Pomace Cell Wall Material: Effect on Wine Phenolic Composition

Fining is a winemaking technique used to remove unwanted wine components that affect clarification, astringency, color, bitterness, and aroma. One of the objectives of fining is often to reduce the wine tannin content due to its effect on wine astringency. Proteinaceous agents are commonly used with this objective, but problems related with their possible allergenic properties or the excessive enrichment of wine with proteins, which may cause stability and turbidity problems, have led to the search for new fining agents. In this way, the cell wall material from processed grape pomace could be a good alternative since it has a high affinity for tannins. In this work, the effect of cell wall material from processed pomace from Monastrell and Cabernet Sauvignon grapes on the reduction of the phenolic content of red wines is studied and the results are compared with those obtained with commercial fining products. Also, the varietal effect due to the different composition of the cell wall material from these two varieties has been evaluated. The concentration and composition of wine anthocyanins and tannins, before and after the fining process, were analyzed by HPLC and their molecular mass distribution by SEC. The results showed that, at laboratory scale, pomace cell walls have a fining effect that exceeds that of most the protein-based fining agents, even when used at their highest recommended doses. The cell wall material significantly reduced the wine phenolic content, the reduction ranging from 48 to 68% for anthocyanins and from 44 to 64% for tannins, although varietal differences exist regarding the cell wall-binding capacity. Monastrell cell walls exhibited the highest capacity and could be used at much lower doses than those used in this study, reducing the formation of lees and the wine adsorbed on them. The results indicate that this material could be an appropriate alternative for protein-based fining agents in red wine and their use would avoid allergen-related effects.     

不同皮渣浸渍发酵时间对葡萄酒中缩合单宁构成及感官品质的影响

为明确不同皮渣浸渍时间对葡萄酒中缩合单宁的影响,以赤霞珠和西拉为材料,进行不同浸渍发酵时间处理,对葡萄皮和葡萄籽以及葡萄酒中缩合单宁的含量、组成、缩合单宁以及相关口感指标等进行了分析.结果 表明,不同葡萄品种中缩合单宁的初始含量、聚合度及没食子酰化率都有显著差异(P＜0.05).葡萄皮中缩合单宁的平均聚合度显著高于葡萄...     

不同酿酒酵母发酵对红葡萄酒中花色苷组成的影响

比较了不同酿酒酵母菌株发酵对红葡萄酒中花色苷组分的影响,为本土酵母的开发应用提供依据。采用本土自筛酿酒酵母菌株Y17和进口商业酵母菌株F15分别酿造干红葡萄酒,并利用高效液相色谱-质谱联用技术(HPLC-MS)对葡萄酒中的花色苷成分进行检测。结果表明,不同酵母发酵葡萄酒中的花色苷成分种类大体相同,但各种花色苷的含量具有较大差别,本土酵母菌株Y17在发酵生产高花色苷含量葡萄酒方面具有优势。     

Volatile Compounds in Red Wines Processed on an Industrial Scale by Short Pre-fermentative Cold Maceration

Nero d’Avola and Shiraz grapes were subjected to pre-fermentative cold maceration at 4°C for about 24 h in industrial winemaking, in order to evaluate the effects of the pre-treatment on aroma profile. The volatile compounds were identified by gas chromatography-mass spectrometry and grouped into 14 chemical families 4 and 9 months after bottling. Principal components analysis (PCA) plots of the volatile compounds showed clear separation among wines from the Shiraz and Nero d’Avola varieties. For instance, Shiraz wines were characterized along the PC1 axe by esters of organic acids, norisoprenoids and C₆ alcohols, while Nero d’Avola wines were characterized by acetates and monoterpenic oxides and diols. Moreover, pre-treated samples showed significant (p?<?0.05) changes in volatile compounds belonging mainly to ethyl esters of straight chain fatty acids, acetates and norisoprenoids. The sensorial analysis showed that cold maceration contributed to development of a different aroma profile during bottle maturation if applied on Nero d’Avola or Shiraz variety.     

Accelerated Aging against Conventional Storage: Effects on the Volatile Composition of Chardonnay White Wines

The effects of time (storage period) and temperature (accelerated aging) on Chardonnay white wines have been evaluated. Attention was focused on a large extent of individual volatile compounds, scarcely previously reported in that kind of wines. On the one hand, several volatile compounds (mainly esters, benzenic compounds, C₁₃‐norisoprenoids, acids, and terpenes) showed the same behavior when temperature and time were applied separately. Therefore, the effect of 1 y of storage could be predicted by temperature application during short time, just analyzing those volatile compounds. Moreover, the formation of some volatile compounds (such as dioxanes, dioxolanes, and 1,2‐dihydro‐1,1,6‐trimethylnaphtalene (TDN)) and the disappearance of some alcohols, terpenes, and furanic compounds occurred in both conventional stored and accelerated‐aged wines. On the other hand, wines submitted to high temperature differed from 1‐y stored wines on several volatile compounds, such as β‐damascenone, C₆‐alcohols, dioxolanes, γ‐butyrolactone, and TDN. Therefore, it is possible to assert that the analysis of these compounds could allow checking the possible inadequate handling by employing an excessive temperature.     

Pectin Concentration, Molecular Weight and Degree of Esterification: Influence on Volatile Composition and Sensory Characteristics of Strawberry Jam

Composition of headspace, consistency, taste and flavor characteristics were determined in jams made with different pectins. At usual concentrations, high methoxylated pectin induced an undesirable modification of typical flavor and intensity of flavor and taste, whereas low methoxylated pectin induced few alterations. At fixed concentration and molecular weight, a decrease in degree of esterification produced a significant decrease in consistency and noticeable modifications of the flavor perception and headspace composition, but no taste alteration. Mechanical reduction of pectin molecular weight significantly modified only the consistency.     

Effects of Carbonic Maceration on Chemical, Physical and Sensory Characteristics of Muscadine Wines

Grapes of four muscadine (Vitis rotundifolia Michaux) cultivars were subjected to carbonic maceration (CM) treatment during vinification. CM involved holding the intact grape berries anaerobically under an atmosphere of CO₂ prior to crushing the grapes. Two different sets of conditions, 20 days at 16°C and 10 days at 24°C, were used for CM treatments. For comparison, standard wines were made from these cultivars by the usual vinification procedures. When compared to the standard wines, CM white wines had lower pH values, higher titratable acidity and phenols, lower alcohol, were yellower in color and were judged significantly lower in sensory quality. CM is not recommended for white wine production. Red CM wines, compared to the standard wines, had higher pH values, had a tendency towards higher volatile acidity, were generally lower in phenols, alcohol and color, and received similar sensory ratings. However, the red CM wines had a distinctively spicy bouquet and flavor which was not present in the standard wines.     

The Effect of Temperature on the Color of Red Wines

The effect of increased temperature on the color of red wines was studied due to its importance during storage and transport. The chemical reactions induced by elevated temperature were investigated by measuring the UV-VIS spectra. The temperature of the wines was increased from its common storage temperature (about 14 °C) to higher temperatures (t= 20 °C, 25 °C, 30 °C, 35 °C, and 40 °C) and the UV/VIS spectra were recorded during several hours. The spectral changes obtained indicate the presence of quasi-first-order chemical processes justifying determination of the activation energies using their temperature dependence. The determined decay values (Villányi Portugieser: E(VP) (a,420 nm) = 90.02 kJ/mol, E(VP) (a,520 nm) = 34.18 kJ/mol, E(VP) (a,620 nm) = 54.55 kJ/mol; half-life values of 46.5 d [25 °C] and 9.5 d [35 °C] at 420 nm; 4.67 d [25 °C] and 2.0 d [35 °C] at 520 nm; 9.5 d [25 °C] and 2.4 d [35 °C] at 620 nm; Bikatory wine: E(Bk) (a,420 nm) = 82.07 kJ/mol and half-life values of 41.35 d [25 °C] and 4.001 d [35 °C] at 420 nm) of these reactions highlight a considerable change in the quality of wines stored for a few hours at elevated temperatures. Depending on polyphenol composition the wines show different half-life with regard to their color stability and browning reactions. Higher polyphenolic content helps to stabilize the wine against detrimental temperature effects. Practical Application: This research can be applicable to estimate the optimal temperature of red wines during storage and transport.     

Sodium Lactate Effect on Sensory Characteristics, Cooked Meat Color and Chemical Composition

Cooked, vacuum packaged beef top rounds injected with 0, 1, 2, 3 or 4% sodium lactate were stored up to 84 days at 0°C. Cooking yields and chemical composition were determined initially, while changes in sensory attributes, Warner-Bratzler shear force and color were evaluated after 0, 14, 28, 42, 56, 70 and 84 days storage. Increasing sodium lactate resulted in higher cooking yields and darker, redder color with less gray surface area. Flavor notes associated with fresh beef were enhanced by addition of sodium lactate, and flavor deterioration during storage was minimized. Palatability was improved by adding 1% sodium lactate, but beyond 1 to 2% it did not further improve. Changes in cooked meat tenderness were verified by Warner-Bratzler shear force measurements.     

Influence of Visual Masking Technique on the Assessment of 2 Red Wines by Trained and Consumer Assessors

ABSTRACT:  During sensory evaluation assessments, visual masking techniques are frequently employed to disguise color differences between samples and minimize perceptual bias. Particularly in wine, the impact of these masking techniques on panelist evaluations has not been well studied. The objective of this study was to study the influence of visual masking techniques on the aroma and flavor assessment of 2 red wines and observe the impact of these techniques on trained and consumer sensory panels. Specific masking techniques included (1) blue wine glass/white illumination; (2) clear glass/red illumination; and (3) clear glass/white illumination. Ten panelists were trained to recognize 7 aroma and flavor attributes, while consumer panelists ( n = 80) evaluated attributes and liking. For the trained panel, the visual masking technique affected only perceived spicy flavor of Syrah ( P ≤ 0.05), with the clear glass/red illumination resulting in more intense spicy flavor compared to the other 2 conditions. Principal components analysis showed that for the 2 red wines evaluated by the trained panel, red illumination resulted in higher spicy attributes and perceived astringency while wines served in blue wine glasses were higher in perceived astringency. For the consumer panel, red illumination resulted in wines higher in perceived astringency and blue wine glasses resulted in wines higher in perceived flavor liking. These results indicated that the visual masking techniques may influence both trained and consumer panel evaluation of aroma and flavor attributes of red wine. However, beyond red wine, this study makes the larger point that the choice of masking technique does impact sensory evaluations.     

Polysaccharide Effects on Cross-Flow Microfiltration of Two Red Wines with a Microporous Alumina Membrane

Two red wines, from the same cultivar, differing by polysaccharide content were filtered using cross-flow microfiltration with an alumina membrane, pore size 0.2 μm. Filtration flow rates were different. The wine richest in polysaccharides (A) showed a typical external fouling profile with progressive stabilization, while wine B showed a permanent decrease in flux (external and internal fouling). Retention of polysaccharides negatively correlated with their hydrodynamic volume, overall losses being higher for wine B. Polysaccharides had a possible role in fouling related to their structures and molecular weight distribution in the two wines.     

气相色谱-质谱法分析比较不同酵母发酵红树莓果酒的香气成分

以红树莓为原料,选取1203、1399、SY、RW、F151、F152 6 种果酒酵母进行发酵,通过顶空-固相微萃取法和气相色谱-质谱联用法分别对6 种果酒香气成分萃取、鉴定、分析和比较。结果表明：6 种酵母发酵的酒液中共检测出159 种香气成分,分别为45、56、67、58、66、39 种,其中相同成分占13 种。6 种果酒中的主要香气成分分别为乙醇、癸酸乙酯、辛酸乙酯、癸酸乙酯、癸酸乙酯、癸酸乙酯,含量依次为15.73%、22.05%、15.74%、18.38%、19.14%、15.24%。通过仪器测定和嗅闻感官综合判断,果酒酵母1399发酵的红树莓果酒香气较好,适宜大众口味。