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Study of the chemical profile of wine of Riesling variety
Šumberová, Michaela ; Trachtová, Štěpánka (referee) ; Vítová, Eva (advisor)
This diploma thesis focuses on the chemical profile and authentication of the geographical origin of varietal wine Rhine Riesling obtained from 4 Moravian wine regions. In the experiment, 20 wine samples were analysed with 5 instrumental analytical methods – aromatic compounds were determined by HS-SPME-GC-MS, phenolic compounds by HPLC-MS, total phenolic content by MAS, and elemental analysis by ICP-OES and ICP-MS. In total 36 aromatic compounds were detected, from which 7 were varietal terpenes and 2 of them C13 norisoprenoids. The total phenolic content for the Rhine Riesling wine was measured in the concentration range of 174,22–380,96 mg·l-1. Gallic acid (0,41–34,99 mg·l-1), catechin (0,05–7,44 mg·l-1), epicatechin (0,03–4,14 mg·l-1), caffeic acid (0,14–2,05 mg·l-1), and coumaric acid (0,30–4,04 mg·l-1) were the specific measured phenolics. In total 18 elements were measured in Rhine Riesling wine, macroelements K > P > Mg > Ca > Na with concentrations above 10 mg·l-1, microelements Al > Fe > Zn > Mn > Sr > Cu in the concentration range 0,1–10 mg·l-1, and trace elements Ni > Cr > V > Pb > Mo > Co > Cd in the concentration 0,0001–1 mg·l-1. Potassium was the most abundant element (386,37 mg·l-1). The results were used for the parametric and nonparametric univariate analysis of variance (ANOVA) and multivariate principal component analysis (PCA). Ni60 (p = 0,0029), ethyl benzoate (p = 0,0060), and diethyl succinate (p = 0,0247) were statistically the most significant parameters influenced by the wine region for the significance level = 0,05. Out of the 57 measured variables 7 parameters were identified as statistically significant and used for PCA graphic representation of the samples. PCA results show, that the varietal wine’s origin can be authenticated by chosen chemical compounds and chemometric methods.
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Využití enologických taninů při výrobě vína
Ryzí, Barbora
The diploma thesis dealt with influence of oenological tannins on white wines. Total influence on sensory character and composition of wine.The teoretic part dealt with antioxidant substances in wine and with oenological tannis and their division and use.The pratical part deals with research of adding of seven types of commercial tannins to wine. The practical part summarizes results of sensory analysis include aromatic profil of wines. The charts with results are showing results of measurement of antiradical aktivity, reducing ability and amount of total phenols and catechins.
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Porovnání kvantitativních a kvalitativních vlastností odrůdy Ryzlink rýnský v ekologické a integrované produkci
Juga, Petr
This diploma thesis are focused on the comparison of integrated and organic production. The literary part deals with the problems of production systems in viticulture and explain their influence on the quality of grapes. It also describes plant extracts, used plants and their production. It describes the main fungal diseases that the vines invade. The experimental part describes the experiment itself, the plant protection products used and the methods used to evaluate the quantitative and qualitative parameters of Riesling grapes that have been observed during maturation. It deals with the evaluation and comparison of the monitored parameters. The thesis recommends an appropriate system of cultivation in organic and integrated production.
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Vplyv odlistenia bielych odrôd viniča hroznorodého na kvalitu hrozna
Soós, Tomáš
The objective of this study was to review findings on effects of defoliation on quality of the white Vitis vinifera grape and to conduct a defoliation experiment. Based on the research of literature, there is an information on defoliation and its effects on grape in the theoretical part of the study. Main focus is on the defoliation as one of the grapevine´s canopy management practices and on particular grape quality characteristics which the defoliation affects. Results of the own experiment carried out on Rizling rýnsky variety are statistically analysed and presented in the second part of the study. Although only some of the actual findings on impact of defoliation on the quality and yield attributes of the grape are supported by the results of this experiment, defoliation is recommended as a viticulture practice worth trying. However, if someone wants to achieve particular results, it is important to choose the right model of the defoliation treatment (right timing, right intensity ...) considering many other factors influencing the quality of the grape.
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Vliv raného termínu odlistění zóny hroznů na kvalitu a zdravotní stav u bílých odrůd révy vinné
Pavlíková, Romana
This bachelor work focuses on timing, intensity and influence of defoliation on quality and physiology of grapevines. In the introduction, brief history of defoliation and mechanical devices used for defoliation are discussed. The main part describes an experiment testing different defoliation timing on Riesling grape quality. At the end of the main part, statistical analysis is presented. The experiment was done in the Mendel university vineyard, in Lednice, in the year 2015. In the end of the work, implications for planter praxis are discussed.
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Hodnocení kvalitativních parametrů hroznů u odrůdy Ryzlink rýnský
Malčic, Kateřina
The main theme of this thesis are qualitative parameters of the grapes. There are generally described various concepts in the first part, such as ripeness, sugar content, sugars, acids, pH and assimilable nitrogen. The work is focused on a white grape variety Riesling. Samples of berries were collected weekly, imported into the laboratory and regularly measured. All collection took place from 35th to 41st week of the year from various locations in the wine region of Moravia. For the final processing of the data was used year 2013. The results were statistically processed into tables and graphs.
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Vliv intenzity odlistění na kvalitu hroznů
Zugárková, Petra
The aim of this thesis was to establish experiment with different dates of defoliation in the zone of grapes, evaluate the infestation by Botrytis cinerea putrefaction, monitor the development of qualitative and quantitave parametres and the content of phenolic compounds. The experiment was conducted at white wine grapes variety Ryzlink rýnský a blue wine grapes variety Carmenere. The literary section describes leaf and its area, microclimate of leaf walls, qualitative parametres, balance of the vineyard, green works, Botrytis cinerea and partial defoliation. Within the experiment were evaluated and controled at the defoliated variation: quality parameters (sugar content, titratable acid pH, assimilable nitrogen, amount of glucose and fructose, tartaric acid and malic acid), infestation by Botrytis cinerea putrefaction, content of phenolic compounds. Measurements were performed at the Department of viticulture and viniculture in faculty of Horticulture in Lednice. Used instruments: TitroLine - pH, titratable acid, assimilable nitrogen; HPLC - tartaric acid, malic acid, glucose and fructose; Spectrophotometer - the content of phenolic compounds; Digital Scale - weight of the grapes. As the most appropriate option in terms of measured parameters was selected the option before the flowering and during the flowering of Ryzlink rýnský and Carmenere.
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