Aromatic characterization of brazilian sparkling wines using olfactometry and a sensory panel

Brazilian sparkling wines, which currently account for 30% of the national production of fine wines, have been traditionally produced in the southern region since the 1910s. In Brazil, sparkling wine production increased 248% over the past 10 years, holding an 80% share of the domestic market wine. The objective of the present study was to establish sparkling wine typicality via aroma characterization by comparing quantitative and descriptive techniques for the main aromatic compounds. Sparkling wines from the major producing regions of Brazil were tested by two sensory panels, followed by gas chromatography analysis that allowed elucidation of their aromatic basis. Solid-phase microextraction was used for the extraction of the compounds, followed by detection using gas chromatography (GC), olfactometry and mass spectrometry (MS). Olfactometry and gas chromatography-mass spectrometry (GC-MS) identified 25 aromatic areas and 26 aromatic compounds, respectively. The majority of aromatic areas were associated with fruit descriptors, but floral aromas were also emphasized; these aromas often contribute to the elegance of sparkling wine and are highly valued by both consumers and experts. Fruity and floral aromas were highlighted by olfactometry. The ester found in the highest concentrations (GC-MS) was ethyl acetate, with a similar value to that found in aged Cavas. Sparkling wine 5 exhibited the highest mean value, which was almost double that of the lowest value in sparkling wine 6. Ethyl octanoate concentrations varied significantly, with sparkling wine 2 containing three times the amount found in sparkling wine 5. Ethyl butanoate values were similar for all sparkling wines. Isoamyl acetate was only found in sparkling wines 4 and 5. The mean concentration values of isoamyl, 1- propanol and isobutanol alcohols were lower than those studied sparkling wines from non-traditional cultivars. The mean values for hexanol were higher, which can be explained by the climatic conditions in southern Brazil. The aromatic description of sparkling wines, as established by the different evaluator groups. Fruity descriptors were predominant. Interestingly, there was a significant presence of roasted aroma descriptors, which are usually due to aging on lees and on oak, demonstrating that certain products develop for a long time. Furthermore, several evaluators described sweet aromas, which suggests good grape maturation and a quality winemaking process. Product complexity was also demonstrated by the description of floral and vegetative aromas. Most often, Brazilian and Italian sensory analysis panels cited pineapple and roasted or apple and fruit individual descriptors, respectively

Method for categorizing wooden part-components in order to make food-grade wooden containers

2nonenoneGarbellotto Piero; Battistutta FrancoGarbellotto, Piero; Battistutta, Franc

Optimization of wine headspace analysis by solid-phase microextraction capillary gas chromatography with mass spectrometric and flame ionization detection

Different novel fibers for solid-phase microextraction were developed in the last years. The aims of this work were the study of their performances in wine headspace analysis, and the optimization of some analytical conditions. The fibers were evaluated for their sensitivity and repeatability; the results showed a strongly different behavior for the different solid-phases, both for the different zones of the chromatogram and for different levels of concentration. A Divinylbenzene/Carboxen/Polydimethylsiloxane fiber coating appeared the most suitable for the analysis of aromatic fraction of wines in its totality. For specific applications, the choice of a suitable solid-phase, depends on the class of compounds be analyzed

Effect of a yeast industrial lysate on the evolution of red wines after bottling

The use of yeast polysaccharides in the stabilization of the phenolic fraction of red wines, is a recent application. Increasing amounts of an industrial product made by thermal lysis of yeast cell walls were added to two red wines: the effects on phenolic and coloring fraction were studied, in relation to bottle storage. The effects on wine color and astringency, showed strongly dependence to the characteristics of the wine and to the dosage; they were limited to short times of conservation. In fact, a loss in the positive effects on color intensity was observed during the bottle storage, probably as a result of the modifications in the colloidal equilibrium during conservation. The complexity of the conditioning factors makes other studies necessaries, in order to optimize this kind of technology

Effect of a yeast industrial lysate on the evolution of red wines after bottling

The use of yeast polysaccharides in the stabilization of the phenolic fraction of red wines, is a recent application. Increasing amounts of an industrial product made by thermal lysis of yeast cell walls were added to two red wines: the effects on phenolic and coloring fraction were studied, in relation to bottle storage. The effects on wine color and astringency, showed strongly dependence to the characteristics of the wine and to the dosage; they were limited to short times of conservation. In fact, a loss in the positive effects on color intensity was observed during the bottle storage, probably as a result of the modifications in the colloidal equilibrium during conservation. The complexity of the conditioning factors makes other studies necessaries, in order to optimize this kind of technology

Sweet-like off-flavor in Aglianico del Vulture Wine: Ethyl Phenylacetate as the mainly involved compound

Interest in high-quality and peculiar products is a recent trend in the enological field; for this reason, production of wines from autochthonous vine varieties is requested by consumers. Aglianico wine from the Italian region "Basilicata" is an example of a promising product strictly connected to the territory; nevertheless, it is affected by a frequent sweet-like off-flavor. In this study the compositional cause of this off-flavor was investigated by SPME-GC-olfactometry, SPME-GC-MS, and sensory tests. Ethyl phenylacetate (EPhA) was found to be the compound mainly responsible, and its sensory threshold was determined near 73 \u3bcg/L; products with the odorant concentration near and up to these values were always recognized as significantly different from the other wines and were often far from wine technical pleasantness; besides EPhA gave to the wines a strong honey-like character. Some preliminary hypotheses about its mechanism of formation (shikimate pathway) are presented in this study: these hypotheses could explain the correlation between EPhA and volatile phenols that was found by both sensory tests and GC quantitative analysis of wines affected by different levels of defect. \ua9 2007 American Chemical Society