Sensory profiling of aroma in Greek dry red wines using rank-rating and monadic scoring related to headspace composition

Rank-rating and monadic scoring were compared in profiling sensory aroma character of 27 Greek dry red wines with 16 attributes. In parallel wine headspace volatiles were quantified using solid-phase micro-extraction gas chromatography but not identified. In rank-rating, 14 aroma attributes showed discriminations with P<0.05 and 11 P<0.001. In scoring, 6 of 16 attributes showed P<0.05. Principal component analysis (PCA) explained 88% variance in rank-rating data, with six significant components (PCs), in scoring 40% in two PCs. PCA analysis of 83 common flavour volatiles explained 48% variance in six PCs. Partial least-squares regression (PLS1) modelling achieved more and better models for attributes using rank-rating, 8 of 14, than for scoring, 3 of 16; PLS2 explained greater variance in rank-rating. For wine sensory/instrumental correlation studies, rank-rating has distinct advantages over monadic scoring in deciding volatiles contributing to sensory character prior to identification strategies such as HRGC–mass spectrometry

Factors influencing sensory quality in red wines of the variety Aghiorghitiko (Vitis vinifera L.) from Nemea

Sensory quality in wines from the indigenous Greek cultivar Aghiorghitiko of Nemea, in 2 years, was studied with multivariate modelling. The appearance, aroma and oral attributes were assessed separately using rank-rating in 13 red Nemea wines, dominated (10 of 13) by Aghiorghitiko, and headspace congeners (51) quantified by solid phase microextraction with gas chromatography. Partial least squares regression (PLS) and discriminant PLS studied relationships between sensory data and congeners, viticultural and oenological data, producers and influence of wood maturations, respectively. Principal component analysis (PCA) spaces for aroma (11 attributes; 64% variance, 3 PCs), congeners (51; 72%, 7 PCs) and oral characters (13 attributes; 77%, 3 PCs) showed similarities in product clustering. Modelling showed clear relationships between sensory character and plant density, wood maturation and producer, respectively. Sensory characters in Aghiorghitiko wines were primarily differentiated by oak maturation and producer influences

Influence of toasting of oak chips on red wine maturation from sensory and gas chromatographic headspace analysis

Red wine from the Greek grape cultivar Aghiorghitiko, was aged in stainless steel with and without wood chips toasted to different degrees (heavily, medium, lightly) and in a 225L American standard oak barrel for 32 days. Headspace concentrations of four wood-derived congeners (furfural, guaiacol, cis and trans oak lactones) were determined over this period after which the wines were bottled, stored and subjected to sensory descriptive analyses. Of the 36 attributes for appearance, aroma and oral characters, 14 were significant in univariate analyses and differentiated wines in a multivariate (principal component analysis) product space explaining 72% variance in two factors. Wines from medium toast wood chips scored highest for woody, vegetative and smoky aromas and flavours but also for bitter taste and astringent mouthfeel and after 14 days had the highest headspace concentrations of furfural and cis oak lactone. Wood-related notes were ranked from heavily and lightly toasted chips, barrel and steel control

A novel approach for analyzing gas chromatography-mass spectrometry/olfactometry data

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Discrimination of brazilian red varietal wines according to their sensory descriptors Discriminação de vinhos tintos Brasileiros varietais de acordo com suas características sensoriais

The purpose of this paper was to establish the sensory characteristics of wines made from old and newly introduced red grape varieties. To attain this objective, 16 Brazilian red varietal wines were evaluated by a sensory panel of enologists who assessed wines according to their aroma and flavor descriptors. A 90 mm unstructured scale was used to quantify the intensity of 26 descriptors, which were analyzed by means of the Principal Component Analysis (PCA). The PCA showed that three important components represented 74.11% of the total variation. PC 1 discriminated Tempranillo, Marselan and Ruby Cabernet wines, with Tempranillo being characterized by its equilibrium, quality, harmony, persistence and body, as well as by, fruity, spicy and oaky characters. The other two varietals were defined by vegetal, oaky and salty characteristics; PC 2 discriminated Pinot Noir, Sangiovese, Cabernet Sauvignon and Arinarnoa, where Pinot Noir was characterized by its floral flavor; PC 3 discriminated only Malbec, which had weak, floral and fruity characteristics. The other varietal wines did not show important discriminating effects.<br>Conduziu-se este trabalho, com o objetivo de determinar as características sensoriais de vinhos tintos brasileiros elaborados com cultivares de uva introduzidos no país há algum tempo e outros, mais recentemente. Para tanto, as características de 16 vinhos tintos varietais brasileiros foram determinadas por um painel formado por enólogos que avaliaram os vinhos de acordo com suas características de aroma e sabor. Isso foi realizado utilizando-se uma escala não estruturada de 90 mm, a qual apresentava a intensidade de 26 descritores que foram analisados pela Análise de Componentes Principais (ACP). A ACP mostrou três importantes componentes, os quais representaram 74,11% da variação total. De fato, o CP 1 discriminou os vinhos Tempranillo, Marselan e Ruby Cabernet, o primeiro deles sendo caracterizado pelos descritores equilíbrio, qualidade, harmonia, persistência, corpo, frutado, especiaria e carvalho, e, os outros dois, pelos descritores vegetal, carvalho e salgado; o CP 2 discriminou os vinhos Pinot Noir, Sangiovese, Cabernet Sauvignon e Arinarnoa, tendo sido o Pinot Noir caracterizado por seu sabor floral; o CP 3 discriminou o vinho Malbec, que teve descritores florais e frutados fracos. Os demais vinhos varietais não apresentaram efeito discriminatório importante

In-depth search focused on furans, lactones, volatile phenols, and acetals as potential age markers of Madeira wines by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry combined with solid phase microextraction

The establishment of potential age markers of Madeira wine is of paramount significance as it may contribute to detect frauds and to ensure the authenticity of wine. Considering the chemical groups of furans, lactones, volatile phenols, and acetals, 103 volatile compounds were tentatively identified; among these, 71 have been reported for the first time in Madeira wines. The chemical groups that could be used as potential age markers were predominantly acetals, namely, diethoxymethane, 1,1-diethoxyethane, 1,1-diethoxy-2-methyl-propane, 1-(1-ethoxyethoxy)-pentane, trans-dioxane and 2-propyl-1,3-dioxolane, and from the other chemical groups, 5-methylfurfural and cis-oak-lactone, independently of the variety and the type of wine. GC × GC-ToFMS system offers a more useful approach to identify these compounds compared to previous studies using GC−qMS, due to the orthogonal systems, that reduce coelution, increase peak capacity and mass selectivity, contributing to the establishment of new potential Madeira wine age markers. Remarkable results were also obtained in terms of compound identification based on the organized structure of the peaks of structurally related compounds in the GC × GC peak apex plots. This information represents a valuable approach for future studies, as the ordered-structure principle can considerably help the establishment of the composition of samples. This new approach provides data that can be extended to determine age markers of other types of wines