The maceration of the solid parts (dregs) of grapes is a fundamental step of wine-making not only for the production of high quality red wines, but also of structured white wines characterized by a ...high content of aromatic compounds. A mathematical model able to describe the time evolution of the phenolic fractions during grape maceration is reported and discussed. While the accumulation of total phenols and catechins in the must/wine during grape maceration can be described by the mass transfer equation introduced by Fick to evaluate the diffusion occurring between two heterogeneous phases, a more complex mathematical approach is introduced to determine the time evolution of anthocyanins. The extraction rate of different phenolic compounds does not seem to vary significantly with the kind of fermentor or the wine-making technology used, but both the yield and chemical composition of the extracts appear to be significantly affected by extraction time
La macerazione delle parti solide dell´uva rappresenta uno stadio fondamentale nella preparazione non solo dei grandi vini rossi, ma anche dei bianchi strutturati e ricchi in componenti aromatici. Viene introdotto e analizzato un modello matematico in grado di descrivere l´evoluzione nel tempo del processo estrattivo a carico della componente polifenolica delle uve sottoposte a macerazione. Mentre per descrivere l´evoluzione nel tempo della diffusione nel mosto/vino dei polifenoli totali e delle catechine è stata impiegata un´espressione ottenuta elaborando l´equazione di Fick, per analizzare quella degli antociani si è dovuto utilizzare un sistema matematico più complesso. Se il tipo di fermentatore utilizzato o la tecnica di omogeneizzazione impiegata non sembrerebbero in grado di condizionare significativamente la cinetica estrattiva, il tempo di macerazione agirebbe non solo modificando sensibilmente la resa, ma anche e soprattutto la selettività del processo e, quindi, la composizione degli estratti ottenuti
In this work we present a new efficient approach to Human Action Recognition called Video Transformer Network (VTN). It leverages the latest advances in Computer Vision and Natural Language ...Processing and applies them to video understanding. The proposed method allows us to create lightweight CNN models that achieve high accuracy and real-time speed using just an RGB mono camera and general purpose CPU. Furthermore, we explain how to improve accuracy by distilling from multiple models with different modalities into a single model. We conduct a comparison with state-of-the-art methods and show that our approach performs on par with most of them on famous Action Recognition datasets. We benchmark the inference time of the models using the modern inference framework and argue that our approach compares favorably with other methods in terms of speed/accuracy trade-off, running at 56 frames per second (FPS) on CPU. The models and the training code are available1.
An antioxidant capacity of selected Bulgarian wines Yoncheva, T., Institute of Viticulture and Enology, Pleven (Bulgaria); Miteva, L; Alexieva, V ...
Acta horticulturae et regiotecturae,
(2010), Letnik:
13, Številka:
1
Journal Article
Recenzirano
The Total Antioxidant Capacity (TAC) of 11 red and 9 white Bulgarian wines was determined using three different methods (TEAC, FRAP and DPPH). Part of the wines was cultivar defined and other part ...was a blend of several grape cultivars. Different vintages were used for some wines to make it possible to compare the influence of aging on the antioxidant capacity of the final product. All red wines possess more antioxidant compounds than the white ones as confirmed by the three methods. The highest TAC from the white wines showed a White wine blend, vintage 2006, and Tamyanka. The lowest TAC had the wine produced form Muskat cultivar. An interesting correlation confirmed by the three methods was observed among the wines Chardonnay vintage 2001,2004 and 2006 - as the oldest one had the best antioxidant characteristics. No significant differences were found between the values for the first 6 red wines with highest TAC - Cabernet sauvignon, vintage 2001,2005,2006, Merlot, Mavrud and Melnik. The Lozishka gamza wine had the lowest antioxidant content. With the aging, the wine Cabernet sauvignon decreased its TAC measured according to the TEAC assay.
La importancia de la iconografía en la moneda griega se hace patente en este estudio, con el que tratamos de interpretar el significado de los tipos con escenas vinícolas. La enorme difusión que ...tuvieron estas piezas da mayor relevancia al mensaje divulgado con su uso, pues además de su valor de intercambio, las monedas griegas ejercían una importante labor de propaganda para su poleis. El simbolismo del que estaban cargadas sus escenas tanto económico, político como religioso, debía ser fácil de interpretar por aquél que las observase.
Se exploró un posible efecto protector del genoma por parte de un derivado de la uva (vino Tannat). Se utilizaron poblaciones celulares haploides y diploides de Saccharomyces cerevisiae como modelo ...eucariota. Muestras celulares se expusieron a H2O2 en medio nutriente. El ADN se analizó por densitometría láser, luego de su aislamiento y separación por electroforesis con campos pulsados. Se aplicó la distribución de Poisson para la determinación de roturas dobles. El número de roturas dobles del ADN y la frecuencia mutagénica aumentaron en función de la dosis de H2O2, disminuyendo la probabilidad de sobrevida. La combinación de H2O2 con vino Tannat aumentó significa-tivamente la probabilidad de sobrevida y disminuyó el número de roturas dobles. No se observó efecto mutagénico por el vino Tannat. Estos efectos pudieron simularse utilizando altas concentraciones de α-tocoferol. Los resultados indican que un derivado de Vitis vinifera puede, en ciertas condiciones, disminuir las dobles roturas de ADN producidas por el H2O2 e incrementar las probabilidades de sobrevida celular. Los blancos involucrados podrían ser, entre otros, componentes intracelulares de las cascadas redox y/o enzimas de reparación del ADN.The aim of this work was to analyse a possible genome protection provided by a grape derivative (Tannat wine) in yeast cell populations exposed to H2O2. Haploid and diploid strains of Saccharomyces cerevisiae were used as eukaryotic model. Cell samples were exposed to H2O2 in a nutrient medium. Chromosomal DNA was analysed after isolation and separation by pulsed field electrophoresis. Double strand breaks were determined by laser densitometry and application of Poisson distribution. Both haploid and diploid cells showed H2O2 dose dependent DNA fractionation, as well as an increase of lethal -and mutation- events. Upon combination of the Tannat wine and H2O2 a significant decrease of double strand breaks was observed, in association with an increase in surviving fractions. No mutagenic effect was observed after wine exposure. Part of the observations regarding protective wine effect were simulated by exposure to high concentrations of α-tocopherol. Present results indicate that a grape derivative could act as a genome protector increasing cell survival probabilities. Among others, the involved molecular targets could be components of transduction redox cascades as well as DNA repair enzymes.
This study was performed to investigate the effects of adding a dual starter on the chemical and sensory characteristics of red wine made of Campbell Early grape. The yeast starter, Saccharomyces ...cerevisiae, and lactic acid bacteria (LAB) starter, Oenococcus oeni, were used for inoculation in the winemaking process for alcoholic fermentation and malolactic fermentation (MLF), respectively. After 200 days of incubation, the chemical compositions of yeast/LAB-added wine (YL-wine) were compared with those of no-starter-added wine (control) and yeast-added wine (Y-wine). The results show that no significant differences were observed in pH, total sugar, and alcohol content among the wine samples, but the malic acid content in YL-wine was significantly reduced, and various esters and higher alcohols were synthesized. The sensory test revealed that the addition of dual starters resulted in improved overall acceptability in wine. This study emphasizes the importance of O. oeni in addition to yeast in making Campbell Early wine.
Individual yeast strains belonging to the Saccharomyces sensu stricto complex were isolated from Amarone wine produced in four cellars of the Valpolicella area (Italy) and characterized by ...conventional physiological tests and by RAPD-PCR and mtDNA restriction assays. Thirteen out of 20 strains were classified as Saccharomyces cerevisiae (ex S. cerevisiae p.r. cerevisiae and p.r. bayanus) and the remaining as Saccharomyces bayanus (ex S. cerevisiae p.r. uvarum). RAPD-PCR method proved to be a fast and reliable tool for identification of Saccharomyces sensu stricto strains and also gave intraspecific differentiation. Restriction analysis of mtDNA permitted to distinguish S. cerevisiae and S. bayanus species and to discern polymorphism among S. cerevisiae isolates. The assessment of the phenotypic diversity within the isolates by gas-chromatographic analysis of secondary fermentation products was explored. Small quantities of isobutanol were produced by most of the strains and higher amounts by some S. cerevisiae strains with phenotypes Gal^sup -^ and Mel^sup -^; all S. bayanus strains produced low amounts of amilyc alcohols. From this study it appears that each winery owns particular strains, with different genetic and biochemical characteristics, selected by specific environmental pressures during the Amarone winemaking process carried out at low temperature in presence of high sugar content.PUBLICATION ABSTRACT
【目的】分析不同酿酒葡萄品种所酿制的干红葡萄酒抗氧化性的差异及其与总酚含量之间的关系。【方法】利用电子顺磁共振波谱仪（Electron Paramagnetic Resonance, ...简称EPR）和福林-肖卡法（Folin-Ciocalteu，简称FC）分别对河北沙城产区5个单品种干红葡萄酒检测DPPH清除率和总酚含量，筛选适当的EPR试验条件。【结果】干红葡萄酒具有很强的抗氧化能力，在样品稀释200倍、反应时间5 min的条件下，各样品清除DPPH自由基的能力以赤霞珠葡萄酒为最强72.31%，宝石解百纳72.23%，梅鹿辄68.31%，西拉和增芳德分别为59.03%和56.34%。梅鹿辄、宝石解百纳和赤霞珠葡萄酒的总酚含量，分别为3 044.43、3 026.92和2 886.81 mg*L-1。西拉和增芳德葡萄酒的总酚含量相对较低，分别为2 085.51 mg*L-1和1 647.64 mg*L-1。【结论】电子顺磁共振法可以简便、快速检测干红葡萄酒的抗氧化性，不同单品种干红葡萄酒DPPH清除能力表现明显不同，自由基清除率与总酚含量之间存在线性正相关，回归方程y=0.01116x+37.327665，相关系数rGAE/DPPHequiv=0.91753。
【Objective】 The purpose of this study was to compare the antioxidant capacities of dry red wines and analyze their relationship with total polyphenol content. 【Method】 The antioxidant properties of five monoverietal dry red wine samples (from the Shacheng viticultural region of China,) were investigated by Electron Paramagnetic Resonance (EPR) spectroscopy using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical as oxidants, and their total polyphenols content were analyzed by FC method.
Extended description:
Le caratteristiche dei vigneti che si trovano nei pressi di Gorizia, le tipologie di uve che vi si ricavano, i vini tipici di questa zona. Come è cambiato il mestiere del ...contadino negli ultimi decenni. Il vino prodotto da Josko Gravner senza l' impiego di sostanze chimiche aggiuntive;intervista a Gravner in merito. Lavoratori nelle vigne e al processo di vinificazione, grappoli d'uva in dettaglio.
Information:
The characteristics of the vineyards near Gorizia, grapes
obtained, and wines producted in this area, specially the natural wine producted by Josko Gravner, without using additional chemicals.
Original language summary:
Le caratteristiche dei vigneti vicino a Gorizia,i tipi d'uva ottenuti e i vini prodotti, in particolare il vino naturale prodotto da Josko Gravner, senza l'utilizzo di prodotti chimici aggiuntivi.
Consumer habits in the Czech wine market Chladkova, H.(Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic))E-mail:chlad@mendelu.cz; Posvar, Z; Zufan, P
Agricultural economics (Praha)
50, Številka:
7
Journal Article
Recenzirano
The paper provides information about the frequency, preferences and occasions of drinking wine in the Czech Republic, as well as places and factors influencing wine purchase. Based on direct ...questioning of 1,000 respondents from the whole Czech Republic, we found that 11.3% of respondents drink wine several times a week, 29.8% at least once a week, 23.2% several times a month, 2.7% do not drink wine at all, 30.3% of respondents drink wine more often than before. About 34% of respondents buy wine several times a month, especially in supermarkets and hypermarkets (45.2%), or in special wine stores (23.8%); 52.5% of consumers prefer quality varietal wine. The top ten wines most often bought are as follows: Frankovka, Cabernet Sauvignon, Mueller Thurgau, Veltlinske zelene, Rulandske bile, Svatovavrinecke, Modry Portugal, Chardonnay, Ryzlink vlassky, Bohemia sekt.
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