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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Application of comprehensive two dimensional gas chromatography to wine analysis

Vestner, Jochen 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: This study focused on the potential of comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOF-MS) for the improved analysis of volatile wine constituents. Solid phase microextraction (SPME) in combination with GC×GC-TOF-MS was successfully used for the detailed investigation of the impact of three commercial Oenococcus oeni lactic acid bacteria (LAB) strains on the volatile composition of Pinotage wines subjected to malolactic fermentation (MLF). Due to increased separation power and enhanced sensitivity obtained by using two orthogonal separations coupled with the structural information provided by deconvoluted TOF-MS spectra, GC×GC-TOF-MS allowed for the identification and semi-quantitative analysis of much larger numbers of compounds compared to previous studies applying one-dimensional gas chromatography. The combination of univariate and multivariate statistical assessment was used as a powerful tool for data interpretation. The obtained results contribute significantly to the understanding of the impact of MLF on the volatile composition of Pinotage wine Some compounds have been linked to MLF for the first time. Moreover, the impact of these commercial starter cultures on the composition of volatile sulfur and nitrogen compounds in the same wines was studied by one-dimensional gas chromatographic methods with headspace injection and solid supported liquid-liquid extraction together with sulfur selective detection and tandem mass spectrometry. This study demonstrated also for the time, the impact of MLF on the composition of volatile sulfur and nitrogen compounds in Pinotage wine. GC×GC-TOF-MS was further used for the evaluation of the suitability of a new phase for stir bar sorptive extraction (SBSE) analysis of wine volatiles. Despite instrumental complications, beneficial extraction properties of the new stir bar phase for especially more polar compounds could be demonstrated. In addition, the extraction ability of this novel phase was evaluated for the analysis of selected thiazoles in wine using heart-cutting two dimensional gas chromatography in combination with nitrogen selective detection. Advantageous extraction performance of the new stir bar phase compared to a conventional polydimethylsiloxane (PDMS) phase for the determined thiazoles was demonstrated. / AFRIKAANSE OPSOMMING: Hierdie studie het gefokus daarop om die potensiaal van omvattende tweedimensionele gaschromatografie gekombineer met vlugtyd massaspektrometrie (GC×GC-TOF-MS) vir die verbeterde analise van vlugtige wynkomponente te ondersoek. Soliede fase mikro-ekstraksie (SPME) in kombinasie met GC×GC TOF MS is met sukses aangewend vir ‘n ondersoek na die impak van drie kommersiële Oenococcus oeni melksuur bakteria (LAB) rasse op die samestelling van die vlugtige fraksie van Pinotage wyne wat appelmelksuurgisting (AMG) ondergaan het. As gevolg van die verbeterde skeidingsvermoë en die verhoogte sensitiwiteit wat verkry word deur twee ortogonale skeidings te kombineer, tesame met die inligting aangaande die molekulêre struktuur wat die die gedekonvoleerde TOF massaspektra verskaf, maak GC×GC-TOF-MS die identifikasie en semi-kwantitatiewe analise van aansienlik meer komponente, in vergelyking met die gebruik van een-dimensionele gaschromatografie, moontlik. Die kombinasie van monoveranderlike asook multiveranderlike statistiese evaluering is gebruik as ‘n kragtige tegniek vir data interpretasie. Die resultate wat verkry is dra tot ‘n groot mate by tot die ontrafeling en begrip aangaande die impak wat AMG op die samestelling van vlugtige komponente in Pinotage wyn het. Daar word ook vir die eerste keer aangetoon dat somminge komponente verband te hou met AMG. Aanvullend hiertoe is die impak wat hierdie kommersiële kulture (wat gebruik word om fermentasie te inisieer) op die voorkoms van swawel en stikstof bevattende vlugtige komponente het bestudeer deur gebruik te maak van een-dimensionele gaschromatografiese metodes met ‘headspace’ inspuiting en vloeistof-voeistof ekstraksie tesame met swawel en stikstof selektiewe deteksie en tandem massaspektrometrie. Hierdie ondersoek werp lig, ook vir die eerste keer, op die samestelling van vlugtige swawel en stikstof bevattende komponente in Pinotage wyn. GC×GC-TOF-MS is ook gebruik vir die evalueering van die toepaslikheid van ‘n nuwe stasionêre fase vir gebruik met roerstaaf sorptiewe ekstraksie (SBSE) vir die analisering van vlugtige komponente in wyn. Ten spyte van instrumentele komplikasies, is die voordele wat hierdie nuwe fase vir die ekstraksie van vernaamlik meer polêre komponete aangetoon. Vervolgens is die ekstraksievermoë van hierdie nuwe fase vir die analise van sekere tiasole in wyn met ‘heart-cutting’ twedimensionaly gaschromatografie in kombinasie met stikstof-selektiewe deteksie gedemonstreer. Verbeterde ekstraksie van die nuwe roerstaaf fase vir die analise van tiasole, in vergelyking met ‘n tradisionele polydimethylsiloxane (PDMS) fase is voorts aangetoon.
12

The use of rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.) as wood alternative in red winemaking

De Wet, Alet 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Wine knowledge has increased drastically in recent years with the aid of scientific experimentation. The producers of wine have increasingly incorporated new wine knowledge into the marketing and innovation of wine products. In parallel with the above, the consumer market has become more aware of winemaking practices and their influence on consumer health. The use of alternative methods and additives in wine are means by which producers have been able to create innovative wine products. This study focused on the addition of rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.) plant material to red wine. Consumer liking, as well as descriptive sensory analysis (DSA) of different red wines made from a range of cultivars with the addition of rooibos and honeybush plant material, was investigated. Another aim of the study was to observe the effect of oxygen addition to red wines treated with rooibos and honeybush plant material. The consumer studies included a number of events where wines treated with rooibos and honeybush material were compared with other commercial wines. The results could not clearly indicate whether consumers liked or disliked the wine products with added rooibos and honeybush plant material. Further refinement of wines with the addition of rooibos and honeybush can serve as topics for future research. Focus on the potential health benefits which can be added to wine from rooibos and honeybush plant material, as a result of inherent antioxidants within both these species, may serve as a novel research topic. The DSA panels identified aroma descriptors that could be related to the addition of wood and leaf or only rooibos and honeybush wood to wine. The addition of oxygen to wines treated with rooibos and honeybush plant material indicated that aromas associated with these treatments are relatively stable in wine undergoing oxidation. This could possibly pave the way for future research on the topic of low sulphur dioxide containing wines. As a result of this study, a commercial wine product called “Rooibos wine” was developed and became available in retail. Further research on this topic and the impact of the addition of rooibos and honeybush material to wine may be of great benefit for the production of innovative wines with unique aroma profiles. / AFRIKAANSE OPSOMMING: Kennis oor wyn het oor die afgelope paar jaar vooruitgegaan met behulp van wetenskaplike eksperimentering. Wynprodusente sluit toenemend nuwe wynkennis in die bemarking en innovering van wynprodukte in. Parallel hiermee het die verbruikersmark baie meer bewus geword van wynbereidingspraktyke en die invloed daarvan op verbruikersgesondheid. Die gebruik van alternatiewe metodes en byvoegings in wyn is maniere waarop produsente innoverende wynprodukte kan skep. Hierdie studie het gefokus op die byvoeging van rooibos (Aspalathus linearis) en heuningbos (Cyclopia spp.) plantmateriaal by rooiwyn. Verbruikers se voorkeur, sowel as die beskrywende sensoriese analise (descriptive sensory analysis [DSA]) van diverse rooi wyn kultivars waarby rooibos en heuningbos plantmateriaal gevoeg is, is geanaliseer. Nóg ’n doelwit van die studie was om die effek van suurstofbyvoeging by rooiwyne wat met rooibos en heuningbos plantmateriaal behandel is waar te neem. Vir die verbruikerstudies is geleenthede aangebied waar wyne wat met rooibos en heuningbos materiaal behandel is met kommersiële wyne vergelyk is. Die resultate kon nie duidelik aandui of die verbruikers gehou het of nie van wynprodukte wat met rooibos en heuningbos behandel is. Verdere verfyning van wyne met bygevoegde rooibos en heuningbos kan as onderwerpe vir toekomstige navorsing dien. Die verhoogde gesondheidvoordele van wyn wat met rooibos en heuningbos plantmateriaal behandel is as gevolg van die inherente anti-oksidante eie aan die spesies, kan dien as fokus vir ʼn nuwe navorsingstema. Die DSA-panele het beskrywende terme vir aromas geïdentifiseer wat verband kan hou met die byvoeging van die hout/blaar of slegs die rooibos- en heuningboshout by die wyn. Die aromas in wyn wat met rooibos en heuningbos behandel is, is gevind om relatief stabiel te bly tydens oksidasie. Dit kan moontlik die weg baan vir toekomstige navorsing oor lae swaweldioksied-bevattende wyne. As gevolg van hierdie studie is ‘n kommersiële wynproduk, genaamd “Rooiboswyn”, ontwikkel en is dit in die handel beskikbaar. Verdere navorsing oor hierdie onderwerp en die impak van die byvoeging van rooibos en heuningbos materiaal by wyn sal moontlik van groot voordeel wees vir die produksie van innoverende wyne met unieke aroma profiele.
13

Vinohradnictví a vinařství z pohledu práva / Viniculture and wine-production from the legal point of view

Doležalová, Jana January 2012 (has links)
The title of the thesis is "Viticulture and winemaking from the legal point of view". The purpose of my thesis is to analyze the Czech legislation of viticulture and winemaking. It is important to include the law of the European Union because it directly regulates the national legislation. The aim of this thesis is to give a complex insight into the valid viticulture and winemaking law. The thesis is composed of seven chapters, each of them dealing with different aspects of the topic. The first chapter is introduction and provides only starting point of the thesis such as terminology. Chapter two is subdivided into six parts and surveys historical background of viticulture and winemaking in the Czech Republic. Each part is devoted to one important era starting in antiquity and explores the evolution till current situation. Chapter Three shows viticulture and winemaking law in the context of the Czech legal system and highlights links between mentioned law and environmental policy. Chapter Four characterizes current EU legislation and focuses on regulations concerning common agricultural policy in the sphere of viticulture and winemaking. Chapter Five outlines Czech legislation and is subdivided into seven parts. It is the main part of the thesis and it reports on the current Czech regulation of...
14

Estudo da influência do processo de cultivo, vinificação e envelhecimento na composição elementar do vinho utilizando a técnica PIXE

Santos, Carla Eliete Iochims dos January 2011 (has links)
O processo de cultivo da uva e elaboração do vinho tinto varietal Marselan foi parcialmente acompanhado junto a uma vinícola do Vale dos Vinhedos (RS, Brasil), com o objetivo de verificar, com técnicas analíticas baseadas em feixes iônicos, como PIXE, alterações elementares no vinho devido ao seu processamento. Amostras de solo, folhas e galhos das videiras, uvas, mosto e vinhos foram coletadas nas etapas mais importantes do ciclo de cultivo da uva e de produção do vinho. Os alvos foram preparados de acordo com as características de cada material e exigências da técnica e, então, irradiados no sistema de PIXE do Laboratório de Implantação Iônica (IFUFRGS). Os resultados, de acordo com as análises estatísticas realizadas com teste t, ANOVA FATOR ÚNICO e Tukey, mostraram que a composição elementar do solo é constituída por Mg, Al, P, K, Ti, Mn, Fe, As, Rb e Zr. Além disso, foi verificada contaminação superficial devido, principalmente, ao Ca e Cu. Quanto ao cultivo, folhas e galhos revelaram a influência das aplicações de produtos químicos pelo acúmulo de alguns elementos no período de latência. A concentração elementar das uvas variou em função do crescimento e amadurecimento dos bagos. Em geral, durante o processo de vinificação e, em especial durante a fermentação, a concentração de vários elementos aumentou. Este foi o caso de elementos como o Mg, K, Rb e Sr. Por outro lado, alguns elementos tiveram um decréscimo na concentração devido a precipitação, como o Ca e o Cu. / The study of the Marselan grape cultivation and winemaking process was partially carried out in a winery located in Vale dos Vinhedos (RS, Brazil). The main goal was to employ ion-based techniques like PIXE in order to obtain elemental variations throughout the production chain of wine. Soil, vine leaves and branches, grapes, must and wine samples were collected at every important step of the production chain. Samples were prepared according to the peculiarities of each material and technique requirements. All PIXE measurements were carried at the Ionic Implantation Laboratory (IF-UFRGS). The data were analyzed with t test, ANOVA ONE WAY and Tukey. The elemental composition of soil comprises Mg, Al, P, K, Ti, Mn, Fe, As, Rb and Zr. Other elements like Cu and Ca were present over superficial layers and might be related to contaminants. With respect to the cultivation process, leaves and branches suffered from the influence of chemicals accumulated during the latency period. The elemental concentration of grapes changed during the berry growth and ripening. In general, later steps including fermentation tended to increase the concentrations of several elements like Mg, K, Rb and Sr. On the other hand, other elemental concentrations decreased due to precipitation, like Ca and Cu.
15

Health aspects of wine antioxidants: Composition and in vitro bioavailability

Irine Ginjom Unknown Date (has links)
The antioxidant capacity of phenolic compounds in red wine is suggested to be responsible for their health-promoting effects. Compared to other wines, little information is available on phenolic compositions and antioxidant capacity of Australian wine. Information related to the fate of these phenolics in the body once consumed is also very limited. The overall aim of this research was to investigate the relevance of red wine consumption as a source of health-giving antioxidants in humans. The phenolic composition of wine was determined using the Folin-Ciocalteu (total phenolic), aluminium chloride (total flavonols), methyl cellulose precipitation (MCP) (total tannins), pH differential (total monomeric anthocyanins), bisulfite bleaching (total polymeric anthocyanin fractions), and liquid chromatographic (LC-MS) (individual phenolics) methods. Antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis-93-ethylbenzthiazoline-6-sulfonic acid (ABTS) and oxygen radical absorbance capacity (ORAC) assays. The phenolic and antioxidant data were then used to establish the relationship between these two parameters in wines from different varieties (Shiraz, Cabernet Sauvignon and Merlot) and winemaking stages (crushing, fermentations, oaking and bottling). By using an in vitro digestion model that mimics the upper gastrointestinal tract (GIT) digestion, the stability of the wine phenolics during digestion was examined. Finally, to gain a better understanding of the post-digestion absorption of wine phenolics, their permeability across Caco-2 cell monolayers was evaluated. A total of 8 monomeric anthocyanins and 17 other phenolic compounds were positively identified in the red wines using LC-MS analysis. Most of the phenolic categories showed some positive correlations with the antioxidant activities but none of the individual phenolic compounds showed a strong correlation with the total antioxidant activity of the wine, implying a combined contribution of many wine phenolics to antioxidant effects. The phenolic compositions and antioxidant activities of three of Australia’s most common red wines varieties - Shiraz, Cabernet Sauvignon and Merlot were not different from each other, possibly due to the variability within each grape cultivar. During the winemaking process, the total phenolic content and the associated antioxidant activity of the wine increased during the fermentation process, as more phenolics are being extracted from grape skin, seeds and stems into the wine. During oak and bottle ageing, the total phenolic contents were stabilised. Most of the wine phenolics were more stable under acidic conditions (pH 2 and 5.5) than neutral or alkaline conditions (pH 7.4 and 9). This may partly explain the stability of the wine phenolics subjected to the acidic (pH 2) gastric digestion and their loss following simulated pancreatic digestion (pH 7.4). In addition, sample pre-treatment procedures prior to LC-MS analysis may have removed some antioxidants in the form of degradation products and/or new polymeric compounds following the in vitro gastric and pancreatic digestion processes. The missing products appeared to be detected by both the Folin-Ciocalteu method and ORAC assay, which measured the phenolic compounds and their antioxidant activity, after the pancreatic digestion. This suggests that the instability of phenolic compounds at pH 7.4, results in the transformation of most of the oral phenolic antioxidants into more stable forms in the GIT, which in turn contribute positively to the overall antioxidant activities of the ingested wine. All of the original wine phenolics had very low permeabilities across Caco-2 cell monolayers, except for syringic acid, p-coumaric acid and an unknown phenolic acid. Limited surface area for absorption (0.33 cm2) and the limited peak detection sensitivity in the LC method may have contributed towards the difficulty in detecting and identifying compounds with low permeability. In addition, extensive metabolism of absorbed phenolics by the Caco-2 cells may occur based on the appearance of several new peaks. However, due to their low concentrations and lack of reference, the identities of the new products and metabolites remain unknown. The present in vitro study suggests that upon ingestion, most of the original phenolic compounds in red wine are lost either through degradation to new compounds and/or complexation with other compounds. However, these products seem to possess some antioxidant activity and may be the key compounds responsible for the health-promoting effects of red wine. The limitation of the present study in detecting and fully identifying these breakdown products and metabolites should be addressed in future studies.
16

Influence of winemaking practices on the chemical characteristics of winery wastewater and the water usages of wineries.

Conradie, Adel 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The production of wine globally has increased over the past years, increasing the volume of water used and wastewater generated for every litre of wine produced. In the past, the small volumes of winery wastewater that were produced by wineries had little effect on the immediate environment. However, with the increasing wine production all around the world, winery wastewater is a rising concern for the contamination of soil and subsurface flow. In order to fully understand the impacts of winery wastewater, it is important to establish the volumes and chemical characteristics of the wastewater, before considering possible treatments. The first aim of this study was to determine the influence of certain winemaking practices on the water usage. Two wineries in the Stellenbosch Winelands District were monitored during two harvests and one post-harvest season. It was evident through this study that water plays a vital role during the production of wine and that water is needed at virtually all the winemaking steps. However, the volume of clean water needed differs immensely during the course of the production process. It was noticed that throughout the harvest period at both wineries the clean water demand was highest and decreased during the course of the post-harvest period and steadily increased again towards the end of the year. The harvest period contributes between 30 and 40% of the yearly water usage at the respective wineries. It was also noticed that certain winemaking practices including filtering with a bulk filter, washing of barrels and bottling contributes heavily to the water usage throughout the year. Activities that increase water usage during harvest include the washing of the press and processing a combination of red and white grapes on the same day. Furthermore, it was identified that one of the wineries used a smaller volume of water on a daily basis and per tonnage during harvest than the other, indicating that the cleaner production strategy established 10 years earlier has a positive impact on their water usage. The second aim of this study was to monitor the raw and treated winery wastewater from the two wineries during a period of 15 months, including two harvests and one post-harvest season. This was done to investigate the characteristics of the raw and treated wastewater. Firstly, to determine the impact of the different winemaking practices on the chemical composition of the wastewater and secondly, to determine the efficiency of the existing constructed wetlands on the wastewater and the characteristics of the treated wastewater. From this study it was possible to make two main observations concerning the chemical oxygen demand (COD) concentrations of the two wineries. Primarily, it was observed there were variations in the raw wastewater characteristics of the two wineries and above all, that both wineries showed a decrease in the COD of the raw wastewater produced. Not only did the decrease in the raw wastewater COD over this period show promising results when a cleaner production plan is established and managed it also seems to show a decrease in the volumes of water used by the respective wineries and increase in quality. / AFRIKAANSE OPSOMMING: Gedurende die afgelope paar jaar het wynproduksie wêreldwyd toegeneem en as gevolg hiervan toenemende hoeveelhede water gebruik en afvalwater gegenereer. In die verlede het die klein volumes kelderafvalwater wat deur wynkelders geproduseer is min effek op die onmiddelike omgewing gehad, maar gegewe die toenemende produksie van wyn regoor die wêreld is daar groeiende kommer oor die besoedeling van gronde en ondergrondse vloei deur kelderafvalwater. Dit is belangrik om die volumes en chemiese eienskappe van die afvalwater te bepaal om die impak van die water ten volle te verstaan, voordat moontlike behandelings oorweeg word Die eerste doel van hierdie studie was om te bepaal hoe sekere wynmaakpraktyke watergebruik beïnvloed. Twee wynkelders in die Stellenbosch Wynland Distrik is gedurende twee parsseisoene en een na-pars seisoen gemonitor. Hierdeur het dit duidelik geword dat water ‘n noodsaaklike rol speel in wynproduksie en benodig word vir feitlik alle stappe in die wynmaakproses. Die volume skoon water wat benodig word verskil wel noemenswaardig tydens die produksieproses. Die gebruik van skoon water van beide kelders was hoog tydens die parsseisoen, het afgeneem gedurende die loop van die na-pars periode en het geleidelik weer toegeneem teen die einde van die jaar. Die parsseisoen dra tussen 30 en 40% by tot die jaarlikse waterverbruik van die onderskeie kelders. Dit is ook opgemerk dat sekere wynmaakpraktyke, insluitend filtrasie met ‘n grootmaat filter, die was van vate en bottelering, grootliks bydrae tot die waterverbruik deur die loop van die jaar. Aktiwiteite wat waterverbruik tydens parstyd verhoog sluit in die gebruik van die pers en die verwerking van ‘n kombinasie van rooi en wit druiwe op dieselfde dag. Daar is ook vasgestel dat een van die wynkelders tydens parstyd ‘n kleiner volume water gebruik op ‘n daaglikse basis asook per tonnemaat wat daarop dui dat die “skoner” produksie strategie wat dié kelder 10 jaar gelede gevestig het wel ‘n positiewe impak op waterverbruik het. Die tweede doel van hierdie studie was om die onbehandelde en behandelde afvalwater van hierdie twee wynkelders te monitor oor 'n tydperk van 15 maande, wat twee paste en een na-pars seisoen insluit. Dit is gedoen om die impak van verskillende wynmaakpraktyke op die chemiese samestelling van die afvalwater te ondersoek asook om die doeltreffendheid van bestaande kunsmatige vleilande in terme van afvalwaterbehandeling te bepaal en die eienskappe van die behandelde afvalwater te ondersoek. Gevolglik is twee belangrike waarnemings oor die chemiese suurstof behoefte (CSB) konsentrasie van die twee wynkelders gemaak. Variasies in die onbehandelde afvalwater eienskappe is waargeneem by beide wynkelders en daar was ‘n afname in CSB van die onbehandelde afvalwater by beide wynkelders. Die afname in CSB van die onbehandelde afvalwater oor hierdie tydperk is belowend en dit blyk dat wanneer ‘n “skoner” produksie plan opgestel en bestuur word dit wel ‘n afname in waterverbruik en verhoog in kwaliteit by die kelders tot gevolg het.
17

Estudo da influência do processo de cultivo, vinificação e envelhecimento na composição elementar do vinho utilizando a técnica PIXE

Santos, Carla Eliete Iochims dos January 2011 (has links)
O processo de cultivo da uva e elaboração do vinho tinto varietal Marselan foi parcialmente acompanhado junto a uma vinícola do Vale dos Vinhedos (RS, Brasil), com o objetivo de verificar, com técnicas analíticas baseadas em feixes iônicos, como PIXE, alterações elementares no vinho devido ao seu processamento. Amostras de solo, folhas e galhos das videiras, uvas, mosto e vinhos foram coletadas nas etapas mais importantes do ciclo de cultivo da uva e de produção do vinho. Os alvos foram preparados de acordo com as características de cada material e exigências da técnica e, então, irradiados no sistema de PIXE do Laboratório de Implantação Iônica (IFUFRGS). Os resultados, de acordo com as análises estatísticas realizadas com teste t, ANOVA FATOR ÚNICO e Tukey, mostraram que a composição elementar do solo é constituída por Mg, Al, P, K, Ti, Mn, Fe, As, Rb e Zr. Além disso, foi verificada contaminação superficial devido, principalmente, ao Ca e Cu. Quanto ao cultivo, folhas e galhos revelaram a influência das aplicações de produtos químicos pelo acúmulo de alguns elementos no período de latência. A concentração elementar das uvas variou em função do crescimento e amadurecimento dos bagos. Em geral, durante o processo de vinificação e, em especial durante a fermentação, a concentração de vários elementos aumentou. Este foi o caso de elementos como o Mg, K, Rb e Sr. Por outro lado, alguns elementos tiveram um decréscimo na concentração devido a precipitação, como o Ca e o Cu. / The study of the Marselan grape cultivation and winemaking process was partially carried out in a winery located in Vale dos Vinhedos (RS, Brazil). The main goal was to employ ion-based techniques like PIXE in order to obtain elemental variations throughout the production chain of wine. Soil, vine leaves and branches, grapes, must and wine samples were collected at every important step of the production chain. Samples were prepared according to the peculiarities of each material and technique requirements. All PIXE measurements were carried at the Ionic Implantation Laboratory (IF-UFRGS). The data were analyzed with t test, ANOVA ONE WAY and Tukey. The elemental composition of soil comprises Mg, Al, P, K, Ti, Mn, Fe, As, Rb and Zr. Other elements like Cu and Ca were present over superficial layers and might be related to contaminants. With respect to the cultivation process, leaves and branches suffered from the influence of chemicals accumulated during the latency period. The elemental concentration of grapes changed during the berry growth and ripening. In general, later steps including fermentation tended to increase the concentrations of several elements like Mg, K, Rb and Sr. On the other hand, other elemental concentrations decreased due to precipitation, like Ca and Cu.
18

Estudo da influência do processo de cultivo, vinificação e envelhecimento na composição elementar do vinho utilizando a técnica PIXE

Santos, Carla Eliete Iochims dos January 2011 (has links)
O processo de cultivo da uva e elaboração do vinho tinto varietal Marselan foi parcialmente acompanhado junto a uma vinícola do Vale dos Vinhedos (RS, Brasil), com o objetivo de verificar, com técnicas analíticas baseadas em feixes iônicos, como PIXE, alterações elementares no vinho devido ao seu processamento. Amostras de solo, folhas e galhos das videiras, uvas, mosto e vinhos foram coletadas nas etapas mais importantes do ciclo de cultivo da uva e de produção do vinho. Os alvos foram preparados de acordo com as características de cada material e exigências da técnica e, então, irradiados no sistema de PIXE do Laboratório de Implantação Iônica (IFUFRGS). Os resultados, de acordo com as análises estatísticas realizadas com teste t, ANOVA FATOR ÚNICO e Tukey, mostraram que a composição elementar do solo é constituída por Mg, Al, P, K, Ti, Mn, Fe, As, Rb e Zr. Além disso, foi verificada contaminação superficial devido, principalmente, ao Ca e Cu. Quanto ao cultivo, folhas e galhos revelaram a influência das aplicações de produtos químicos pelo acúmulo de alguns elementos no período de latência. A concentração elementar das uvas variou em função do crescimento e amadurecimento dos bagos. Em geral, durante o processo de vinificação e, em especial durante a fermentação, a concentração de vários elementos aumentou. Este foi o caso de elementos como o Mg, K, Rb e Sr. Por outro lado, alguns elementos tiveram um decréscimo na concentração devido a precipitação, como o Ca e o Cu. / The study of the Marselan grape cultivation and winemaking process was partially carried out in a winery located in Vale dos Vinhedos (RS, Brazil). The main goal was to employ ion-based techniques like PIXE in order to obtain elemental variations throughout the production chain of wine. Soil, vine leaves and branches, grapes, must and wine samples were collected at every important step of the production chain. Samples were prepared according to the peculiarities of each material and technique requirements. All PIXE measurements were carried at the Ionic Implantation Laboratory (IF-UFRGS). The data were analyzed with t test, ANOVA ONE WAY and Tukey. The elemental composition of soil comprises Mg, Al, P, K, Ti, Mn, Fe, As, Rb and Zr. Other elements like Cu and Ca were present over superficial layers and might be related to contaminants. With respect to the cultivation process, leaves and branches suffered from the influence of chemicals accumulated during the latency period. The elemental concentration of grapes changed during the berry growth and ripening. In general, later steps including fermentation tended to increase the concentrations of several elements like Mg, K, Rb and Sr. On the other hand, other elemental concentrations decreased due to precipitation, like Ca and Cu.
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Analýza významu enoturistiky pre vinohradníctvo a vinárstvo Slovenskej republiky / Analysis of the importance of enoturism for viticulture and winemaking in Slovakia

Dobošová, Jana January 2012 (has links)
This diploma thesis analyzes the importance of wine tourism - enotourism for viticulture and winemaking in Slovakia. The main aim of this work is determining the relevance and importance of this form of tourism for wine producers. The theoretical part states the base for the research design and provides the introduction into wine tourism. It also describes the current situation of the viticulture and winemaking in Slovakia as well as the situation of the tourism industry and its performance. The analytical part of the work deals with the evaluation of the current situation of wine tourism in Slovakia and assumptions of its development. The core of the analytical part is a questionnaire survey, which charts the attitudes and opinions of the wine producers on issues of winemaking, wine business and wine tourism in Slovakia. The final part analyzes the questionnaire survey supported by theoretical bases of the first part of the thesis and evaluates the importance of enotourism for viticulture and winemaking in Slovakia. This part includes also suggestions for improving the cross-sectorial links between tourism, viticulture and winemaking in Slovakia in order to expansion of this form of tourism.
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Ochrana spotřebitele na trhu vína v ČR / Consumer protection at the Czech wine-market

Simajchlová, Petra January 2012 (has links)
The goal of the Master's Thesis is to identify potential risks that consumers face at the wine market in the Czech Republic. Further, the Master's Thesis aim to find out what are the measures that protect a consumer and to suggest solutions to those areas where the protective measures do not work. The identification is carried out via the analysis of primary and secondary data. Primary data are surveyed by means of consumer research and interviews with experts. At the end of the Master's Thesis the results are summarized and the improving arrangements are put forward.

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