Aroma Compounds as Markers of Wine Quality in the Case of Malvazija Istarska Young Wine

Abstract

In order to investigate the relationship between sensory and gas chromatographic analysis data, and to establish if particular aroma compounds could be used as Malvazija istarska young wine quality markers, 30 samples of Malvazija istarska young wine were subjected to sensory evaluation and gas chromatographic analysis of aroma compounds. Linear regression and principal component analysis were applied in order to establish the relations between sensory evaluation scores and aroma compound concentrations in corresponding wines. The most important contributors to the characterization and differentiation of wines evaluated with higher sensory evaluation scores were isoamyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, hexanoic acid, octanoic acid and decanoic acid. On the other hand, wines evaluated with lower sensory evaluation scores were characterized and differentiated by higher amounts of isoamyl alcohol and isobutanol. Mentioned esters and acids were also found to be the most important variables for the classification of these wines according to quality using stepwise linear discriminant analysis (SLDA). The evaluation of the SLDA model was performed by cross-validation, obtaining an average percentage of correct classification of 100.0%, and of correct prediction of 89.3%. The results of this investigation suggest that above-mentioned esters, acids and alcohols could be used as markers of Malvazija istarska young wine quality.Wine aroma is one of the most important parameters responsible for its quality, and hence for consumer acceptance. Sensory evaluation is the most common technique for controlling the organoleptic quality of wine, but it is not always feasible, since it requires specific conditions, and a group of trained expert tasters that can only assess a relatively small number of wine samples for a day. Moreover, the subjectivity of panelists can affect the evaluation in a great measure. The approach proposed in this work suggests the use of a nonsubjective instrumental technique such as gas chromatography for the analysis of volatile aroma compounds as a complementary tool for wine quality control able to predict, confirm or to correct the results of Malvazija istarska young wine sensory evaluation. Although this model is yet far from being practically implemented, information obtained could be used as a starting ground. Moreover, it was assumed that the approach proposed in this work is likely to be applied successfully on the differentiation and classification of other types of wine according to quality. 718 I. LUKIĆ ET AL. 720 I. LUKIĆ ET AL.

Phenol and Aroma Composition of White Wines Produced by Prolonged Fermentative Maceration and Maturation in Wooden Barrels

“…In fact, these wines were characterised by a typical aroma profi le of young white wines dominated by fruity esters and fatty acids, complemented by a signifi cant contribution of β-damascenone, which corresponds to previous fi ndings on Malvazij a istarska wines (26). Besides a notable impact of straight-chain esters and β-damascenone, the most infl uential odourants in the wines produced by prolonged maceration and maturation were the compounds that originate from wood (lactones and eugenol), compounds oft en associated with fermentative maceration (higher alcohols, linalool), compounds mostly or exclusively generated by species other than yeasts (ethyl acetate, 4-ethylguaiacol, ethyl lactate) or in (semi)aerobic conditions and at higher temperatures (ethyl acetate, ethyl 3-methylbutyrate, isoamyl alcohol), as well as compounds whose concentration typically increases with ageing (ethyl acetate, ethyl 3-methylbutyrate, isoamyl alcohol, TDN, ethyl lactate).…”

Impact of Alternative Skin Contact Procedures on the Aroma Composition of White Wine

“…This effect was not detected for other varieties or maceration procedures by some authors (Tamborra et al, 1992;Cabaroglu et al, 1997;Peinado et al, 2004;Selli et al, 2006). As reported previously, higher concentrations of total higher alcohols are not desired when combined with lower ester content (Ferreira et al, 1995;Lukic et al, 2008). For Zelen and Ribolla Gialla the solvent odour had significantly less impact in Fp and Fg compared to K, for Malvasia Istriana only Fg produced the same effect.…”

“…The lower concentration of grape-derived aromatic compounds from neutral varieties are manipulated by fermentative aromatics like esters, higher alcohols and volatile phenols. (Cabaroglu et al, 1997;Selli et al, 2003;Peinado et al, 2004;Cabrita et al, 2006;Sanchez Palomo et al, 2007;Lukic et al, 2008;Rodriguez Bencomo et al, 2008). In these wines made from neutral grapes, the aroma perceived is a result of the combination of various compounds and cannot be contributed to an individual aromatic component.…”

“…Additionally, it was relevant to determine some olfactory important compounds in the Zelen and Ribolla Gialla wines, as only aromatic data for Malvasia Istriana var. are available (Kovacevic et al, 2005;Lukic et al, 2008). Finally, the sensorial evaluation (odour, overall impression) of wines and the statistical analysis (principal component analysis) were performed.…”

Differentiation of Commercial PDO Wines Produced in Istria (Croatia) According to Variety and Harvest Year Based on HS-SPME-GC/MS Volatile Aroma Compounds Profiling

“…Because of the lack of objective scientific information, knowledge on the varietal typicity of wines from native Croatian grape varieties is still on an informal level. For example, there is published data on the composition of wines made from Malvazij a istarska, the most spread and important native white grape variety in Croatia grown principally in the region of Istria (9,(22)(23)(24)(25), but the volatile compounds and their particular concentrations, indicators of its varietal origin and drivers of its varietal typicity, on the basis of which it might be distinguished and diff erentiated from other monovarietal white wines, are still unknown. On the other hand, Chardonnay is a globally spread and known variety, and its wine aroma has been investigated extensively (26)(27)(28)(29)(30).…”