931 resultados para wine legislation
Resumo:
The fate of folpet from the treatment on vine to the production of wine was studied. Sunlight degraded folpet to unknown products. Phthalimide was a minor metabolite formed on grapes from folpet. Folpet degraded in must, giving 80% phthalimide; the results obtained with model solutions showed that in must folpet can also give small amounts of phthalic acid. During wine-making folpet degraded completely, and at the end of fermentation phthalimide was only present in wine. This compound was stable in wine after several months. The presence of folpet in grapes inhibited the alcoholic fermentation of Saccharomyces cerevisiae and Kloeckera apiculata completely. Phthalimide, on the contrary, had no negative effect on the fermentative action of the two yeasts. GC and HPLC methods were developed to determine folpet and its metabolites.
Resumo:
The fate of four new fungicides (cyprodinil, fludioxonil, pyrimethanil, and tebuconazole) from the treatment on vine to the production of wine was studied. The influence of clarifying agents (bentonite, charcoal, potassium caseinate, gelatin, and polyvinylpolypyrrolidone) on residue concentrations in wine was also studied. The fungicide residues on grapes showed different decay rates after treatment, with first-order kinetics and half-lives ranging from 8 to 57 days. Grape processing into wine caused considerable residue reduction with cyprodinil (ca. 80%), fludioxonil (ca. 70%), and tebuconazole (ca. 50%) and no reduction with pyrimethanil. The two wine-making techniques employed (with and without maceration) had the same influence on the residue concentrations in wine, except for fludioxonil which showed maximum residue reduction with vinification with maceration. Among the clarifying agents tested, only charcoal showed effective action on the elimination of residue content in wine, proving complete elimination, or almost, of fungicide residues.
Resumo:
A rapid and simple gas chromatographic method for determinating cyprodinil, fludioxonil, pyrimethanil, and tebuconazole in grapes, must, and wine is described. An on-line microextraction method was used with a one-step extraction-partition procedure. Nitrogen-phosphorus and mass spectrometric detectors were used, because of their low sensitivity and high selectivity. Because of high selectivity of detector, no cleanup was necessary and the extract was concentrated 5 times. Recoveries from fortified grapes, must, and wine ranged from 93 to 110%. Limits of determination were 0.05 mg/kg for cyprodinil and pyrimethanil and 0.10 mg/kg for fludioxonil and tebuconazole.
Resumo:
This study investigated the postprandial plasma responses of carotenoids for 24 h after feeding five specific breakfast beverages; four of which had low or no carotenoid content. In seven fasting healthy elderly female subjects a blood sample (baseline) was obtained, after which they were given a breakfast beverage, containing one of the following: 1) strawberries (240 g); 2) ascorbic acid (1250 mg); 3) spinach (294 g); 4) red wine (300 mL); and 5) control (breakfast beverage only). Blood samples were collected at 0.5, 1, 4, 7, 11, 15 and 24 h. Plasma carotenoids were measured using HPLC. No significant differences were found in the levels of the plasma carotenoids measured among the various treatments at baseline. In the spinach treatment, plasma lutein, zeaxanthin and β-carotene levels at 7, 11, 15 and 24 h were significantly higher than those at baseline, as expected. All of the carotenoids measured in the control and vitamin C treatments, at subsequent sampling times were not significantly different from those at baseline. However, for most carotenoids, strawberry and red wine feeding resulted in significantly lower carotenoids values from baseline at 11 and 15 h. Subjects who received a diet with low levels of carotenoids, but whose postprandial plasma levels of carotenoids remain steady, might be explained by a mechanism that promotes secretion of carotenoids into the circulation. Assuming that plasma carotenoids are being used over time, we hypothesize that strawberries and red wine contain some substances that interfere with the secretion of carotenoids into the circulation.
Resumo:
Includes bibliography
Resumo:
Incluye Bibliografía
Resumo:
Includes bibliography
Resumo:
Microbial β-glucosidases have been used for the enhancement of wine aroma. Nevertheless, few enzymes are active in the conditions of winemaking. In this work, the production of a β-glucosidase by an Aureobasidium pullulans strain (Ap-β-gl) isolated from grape ecosystems was evaluated. The maximum enzymatic synthesis using submerged fermentation was after 96 h of growth in complex media containing 20 g/L of cellobiose as the sole carbon source. The crude enzyme (Ap-β-gl) showed optimal pH at 5.5 and two peaks of optimum temperature (at 45 and 70 C). It showed a wide range of pH stability, stability at low temperatures, and tolerance to ethanol, showing suitable characteristics for winemaking conditions. The hydrolysis of glycosidic terpenes by Ap-β-gl was studied, and its ability to efficiently release free terpenols was demonstrated by gas chromatography/mass spectrometry. The enzymatic treatment notably increased the amount of monoterpenes, showing good prospects for its potential application for the development of aroma in wines. © 2012 Springer Science+Business Media New York.
Resumo:
Incluye Bibliografía
Resumo:
An extracellular ethanol-tolerant β-glucosidase from Sporidiobolus pararoseus was purified to homogeneity and characterized, and its potential use for the enhancement of wine aroma was investigated. The crude enzymatic extract was purified in four steps (concentration, dialysis, ultrafiltration, and chromatography) with a yield of around 40 % for total activity. The purified enzyme (designated Sp-βgl-P) showed a specific activity of approximately 20.0 U/mg, an estimated molecular mass of 63 kDa after sodium dodecyl sulfate polyacrylamide gel electrophoresis, and isoelectric point of 5.0 by isoelectric focusing. Sp-βgl-P has optimal activity at pH 4.0 and at 55 °C. It was stable in a broad pH range at low temperatures and it was tolerant to ethanol and glucose, indicating suitable properties for winemaking. The hydrolysis of glycosidic terpenes was analyzed by adding Sp-βgl-P directly to the wines. The released terpene compounds were evaluated by gas chromatography/mass spectrometry. The enzymatic treatment significantly increased the amount of free terpenes, suggesting that this enzyme could potentially be applicable in wine aroma improvement. © 2013 Springer Science+Business Media New York.
Resumo:
Includes bibliography
Social security planning in the Caribbean: contributory provident fund scheme with draft legislation