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Předfermentační postupy ve vinařské technologii
Pitra, Martin
The bachelor thesis was elaborated in the years 2018 and 2019 at the Department of Post-Harvest Technology of Horticultural Products of the Faculty of Horticulture of Mendel University in Brno. The thesis gives an overview of pre-fermentative procedures or treatments that can be applied in the process of producing white, rosé and red wine. The pre-fermentative procedures are divided into groups according to the color of the grape and the color of the wine produced. Pre-fermentative procedures used inde-pendently of the color of the grapes or the wine produced also have their group. Data were obtained from six studies in which white wines were produced based on mash maceration with temperature reduction and enzymatic mash treatment. The data related to the concentrations of identified terpenes and their OAVs (Odor Activity Value) were processed and compared. Based on the OAVs of the evaluated and control wines in their studies, their percentage differences were calculated and used as a basis for com-paring the efficacy of the applied pre-fermentative treatments.
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Využití enzymů ve vinařství
Brůčková, Jana
This Bachelor work is about usage of enzymes in viticulture. It describes enzymes which are included in grapes and usage of commercial enzymes in viticulture. In the end of the work are summarized some studies which are deal with usage of commercial enzymes and their influence on the quality and features of wine.
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Specifika výroby vín v kvevri
Franta, Tomáš
This diploma thesis discusses the specifics of qvevri wine-making method, that represents very ancient footprint of wine technology. There are described and compared traditional wine-making methods with those which are used dominantly in wine-producing countries. The thesis deals with the chemical composition of wines vinified by different technologies. The knowlage gained from literary sources is compared eith the results of the experimental part.
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Studium flavonoidů v červených vínech
Kandourova, Alexandra
This diploma thesis deals with study of flavonoids in red wine. This dissertation is divided into two parts: theoretical and practical. Theoretical part is define phenolic compounds, pays attention to flavonoids as important polyphenols which influence quality of red wines. The particular subchapters pay attention to maceration, respectively cryomaceration. The aim of the experimental part of this diploma thesis was to compare wines from Pinot noir. The wines were produced by two ways of maceration: fermentative maceration and cryomaceration at 4, 5°C for 3, 7, 14 days. At the same time, the effect of post-fermentation maceration was monitored in these two ways too. For wines was investigated the content of phenolic compounds, anthocyanins, flavanols content of catechin, epicatechin and antioxidative activity. Fermentative maceration positively influenced the content of total phenolic substances and post-fermentation maceration increased the catechin and epicatechin concentration. For red wines, cryomaceration appears to be a desirable step in production.
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Využití suchého ledu v technologii vín révy vinné
Holešinský, Radim
This Diploma thesis contains information about cryomaceration and using of dry ice in wine technology. Base on that we could compare differences in basic wine parameters or amount of fenolic and sensoric contrasts in mature wines. In theoretical part of this thesis are describe principles of cold maceration or cryomaceration, but main focus was on maceration method with dry ice. In next part we oriented on calculating total costs and usefulness of dry ice. Final part is all about maceration and squeezing of blue grapes. In the beginning of experimental part is described variety Frankovka in general, which was used to this experiments. In following article is explained how the experiment was handled, what practices were used for it and why I chose analytic and sensoric method for this experiment. In Final part are presented graphs, results, conclusions we made in this experiment.
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Porovnání komerčně dostupných maceračních enzymů při výrobě bílých vín
Maleňáková, Daniela
This bachelor thesis deals with the influence of macerating enzymes in the white wine production. The use of enzymes, description of pectins and their change during the production of wine, and various types of maceration are described in detail in the literature review. The main aim of this work was to map macerating enzymes commercially obtainable in the Czech Republic and select representative sample for experimental part. Pomace from crushed grapes was divided into 9 batches, treated with enzymes and macerated for 24 hours. The pomace was pressed and stripped subsequently. The yield values, basic parameters and the polyphenolic profile of the must were evaluated for all samples. An evaluation of the enzymes parameters was performed based on these measurements. The results of measurements revealed that the best results were achieved by the Lallzyme Cuvee Blanc enzyme from LALLEMAND company.
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Využití třapin v technologii vín révy vinné
Helmová, Tereza
The bachelor thesis on The use of grape vines in the technology of wine grape vines in the first part deals with the literary summary on the given topic, namely the composition of grapes, the principle of maceration and Frankovka as a variety. Further, the bachelor thesis develops in the experimental part, which consists in the maceration of certain parts of the stems. The Frankovka variety is used for the experiment. The results of the experiment consist of sensory evaluation and chemical analysis.
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Aronia as a raw material for cosmetic production
Palkovská, Kateřina ; Sýkora, Michal (referee) ; Zemanová, Jana (advisor)
This bachelor thesis deals with extraction of polyphenols from fruits and leaves of aronia and consequent use of obtained extract in cosmetic production. In the theoretical part are information about the origin of the aronia, the botanical characteristics of Aronia Melanocarpa and about its utilization. Furthermore, the chemical composition of the plant material of the aronia is described, which is also common for fruits. At the end of the theoretical part are described extraction and separation techniques, methods of determination of total polyphenolic compounds and brief characteristics of the material safety data sheet. The experimental part describes the optimization of the prepared extract so that the extract contains as many polyphenolic compounds as possible. 50% ethanol at room temperature was shown to be optimal for leaf and fruit extraction, and the maceration time was found to have a significant effect on the polyphenolic compounds obtained. For the obtained optimized macerate, some chemical and physical properties such as pH, density, refractive index were determined for the purpose of producing a material safety data sheet and product specification. At the end of the experimental part were prepared cosmetic products with the addition of macerate from crushed aronia fruits.
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Vliv různých technik studené macerace na obsahové látky vína
Blasch, Jiří
This bachelor thesis deals with the composition of wine, describes cold maceration and its effect on extraction of substances from white and blue grape varieties. The thesis describes technology for grapes cooling and its use in viticulture. The effort was put on summarization of current knowledge of maceration methods which were further used in experiment with Riesling variety. Different methods of pre-fermentation maceration (in terms of contained substances and sensory feeling) were compared.
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