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61.
Giuliano Dragone Solange I. Mussatto João B. Almeida e Silva 《European Food Research and Technology》2008,228(2):257-264
Flavor compounds’ formation and fermentative parameters of continuous high gravity brewing with yeasts immobilized on spent
grains were evaluated at three different temperatures (7, 10 and 15 °C). The assays were performed in a bubble column reactor
at constant dilution rate (0.05 h−1) and total gas flow rate (240 ml/min of CO2 and 10 ml/min of air), with high-gravity all-malt wort (15°Plato). The results revealed that as the fermentation temperature
was increased from 7 to 15 °C, the apparent and real degrees of fermentation, rate of extract consumption, ethanol volumetric
productivity and consumption of free amino nitrogen (FAN) increased. In addition, beer produced at 15 °C presented a higher
alcohols to esters ratio (2.2–2.4:1) similar to the optimum values described in the literature. It was thus concluded that
primary high-gravity (15°Plato) all-malt wort fermentation by continuous process with yeasts immobilized on spent grains,
can be carried out with a good performance at 15 °C. 相似文献
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63.
Teresa Ortega Elena De La Hera M. Emilia Carretero Pilar Gómez-Serranillos M. Victoria Naval Angel M. Villar Marin Prodanov Visitación Vacas Teresa Arroyo Teresa Hernández Isabel Estrella 《European Food Research and Technology》2008,227(6):1641-1650
Red wine has been reported to exert beneficial effects in preventing cardiovascular diseases probably due to their polyphenols
constituents. The vasorelaxant capacity and phenolic composition of four monovarietal young red wines Merlot, Tempranillo,
Garnacha and Cabernet-Sauvignon obtained from grapes from 2004 vintage, cultivated under the same climatic and agricultural
conditions, wine-making technology and storage conditions, were determined using vascular reactivity assay in rat aortic and
high-performance liquid chromatography, respectively. Primary cultures of vascular smooth muscle cells from Wistar rats were
also used to evaluate their survival prevention activity as well. Every studied wine present vasorelaxation effect, but the
higher value corresponds to the analyzed Merlot wine, especially rich in phenolic compounds, mainly catechins and oligomeric
proanthocyanidins and anthocyanin glycosides. This study further demonstrated previous investigations about the phenolic composition
of wines relation with their vasorelaxation activity. 相似文献
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69.
The production of yellow pigments from (+)-catechin and dihydroxyfumaric acid in a model wine system
Andrew C. Clark 《European Food Research and Technology》2008,226(4):925-931
The oxidation of tartaric acid by hydroxyl radicals, produced by gamma-irradiation of aqueous solutions of tartaric acid,
was shown to generate dihydroxyfumaric acid. To confirm the importance of this oxidative degradation pathway in wine oxidation,
dihydroxyfumaric acid was itself reacted with (+)-catechin in a wine-like solution and the yellow pigments formed were identified
by liquid chromatography mass spectrometry (LC-MS) studies as xanthylium cations. The concentration of these pigments increased
if the wine-like system also contained 0.6 mg/L copper(II). The results clearly demonstrate a link between the production
of yellow xanthylium cation pigments from (+)-catechin and the degradation of tartaric acid by hydroxyl radicals. 相似文献
70.
Miriam Ortega Heras M. Dolores Rivero-Pérez Silvia Pérez-Magariño Carlos González-Huerta Mª Luisa González-Sanjosé 《European Food Research and Technology》2008,226(6):1485-1493
Microoxygenation is a wine-making technique consisting in the addition of small and controlled amounts of oxygen. This study
has examined the effect of this technique on the volatile composition of two red single variety wines during two successive
vintages. The microoxygenation treatment was applied at the end of alcoholic fermentation and before beginning malolactic
fermentation. Once the microoxygenation treatment had finished, wines were aged in new American oak barrels for 12 months.
The results obtained showed that the microoxygenation treatment did not cause significant changes in the varietal and fermentation
volatile compounds, however microoxygenation slowed down the extraction of some of the volatile compounds extracted from wood.
A varietal and vintage effect was also observed for some of the compounds studied. 相似文献