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The thesis "Production and Evaluation of Fruit Wines" was prepared in 2016/2017 at the Institute of Postharvest Technology of Horticultural Products at the Faculty of Horticulture of the Mendel University in Brno. The thesis deals with the production of fruit wines with a focus on their fabric composition. In the practical part, based on analytical and sensory analyzes, samples of wines, laboratory samples of wines from the wine-growing and retail networks were evaluated. The data obtained were statistically compared and appropriately interpreted. The currant and cherry wines were sensitively evaluated above the apple. And currant and cherry wines have shown a higher antioxidant capacity.

In the teoretical part of this thesis is breefly written about history of brewing beer, beer ingredients, brewing proceses and methods by which the beer is analyzed (instrumental and sensoric methods) and also contains legislative requirements for herbal beers and for beverages that are based on beer. In the practical part are mentioned processes of making beer using herbs and other materials. The final product is beer containing extracts of lemon balm (Melissa officinalis L.) and common yarrow (Achillea millefolium agg.). Antioxidant capacity was defined by DPPH and FRAP methods. To monitor sensory acceptance for herbal beers sensory analysis was used.

Climate change is characterized by higher average temperatures, more frequent extreme weather events such as torrential rains, floods, frost and snow cover absence, absence of snow cover and longer episodes of drought. In the 21st century is likely to shift production areas where surface area of corn and sugar beet will be increased. In corn production areas will be achieved lower yields than in sugar beet in 2020. Around 2030, the most suitable conditions for growing wheat sown in sugar beet and potato production area. The last part was determined from the data of the Central Control and Testing Institute for Agriculture of the Czech Hydrometeorological Institute and the relationship between the moisture regime selected sites in different stages of the growing season and yield lines. Statistically significant correlations between yield and available water holding capacity (AWHC) was observed at stations Uherský Ostroh, Pusté Jakartice, Lípa and Věrovany.

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This thesis dealing with the study of antioxidant capacity was developed between 2006-2011 at the Department of Post-Harvest Technology of Horticultural Products, Faculty of Horticulture, Mendel University in Brno. The aim of this thesis was the evaluation of photo-chemiluminescence method and its optimization for determining the antioxidant capacity by the Bux Photochem device. The assessment of impact of selected substances and treatment of experimental material on measured values of antioxidant capacity. The other aim of this thesis was the monitoring of development of antioxidant capacity of the grapes during ripening period and during the process of alcoholic fermentation. The basic principles of measuring the antioxidant capacity by photo-chemiluminescence method are provided by compliance of the methodology with an emphasis on the same treatment of the device. The work showed that the dilution of the observed samples affects the antioxidant capacity measured by Photochem Bux PCL. The solutions of the reference wine and the antioxidant rutin showed higher antioxidant capacity at the samples with higher dilution level. At the parallel extraction by non-polar and polar extractants and the subsequent summation of the measured values of TAC was shown that the resulting value was higher than at the consecutive extractions. Therefore the summation of the values is not appropriate for parallel extractions of antioxidants obtained from the extractants with various polarities. During the extractions 75% methanol was evaluated as the best extractant of antioxidants present in grapes. It is necessary to homogenize the sample before extraction. All the extraction operations must be finished in the shortest time possible. It was shown that all the extraction operations apart from used extractant and re-extraction have demonstrable effects on degradation of antioxidants extracted from the samples. Therefore it is necessary to describe all the extraction procedures perfectly. Very suitable extraction procedure is a re-extraction. There is a big difference in concentrations of extracted substances and extractant occurring during re-extraction, so the extraction is very effective. It was observed that one of the factors causing the degradation of antioxidant compounds during the extraction procedures is the presence of atmospheric oxygen. Sulphites present in wine do not affect the value of antioxidant capacity measured by photo-chemiluminescence method. Conversely, FRAP method has a positive response to the presence of sulphites in wine, so the values measured by this method are affected by the sulphites content. The impact of alcohol content on antioxidant capacity measured by photo-chemiluminescence method was not demonstrated. The monitoring of the antioxidant capacity development in grapes during the ripening period showed that the white varieties have no characteristic development. The blue varieties showed that during the ripening period the values of antioxidant capacity were gradually increasing up to three times the first measurement (46 days before the harvest). The antioxidant capacity of grape juice was increasing during the alcoholic fermentation only if the juice was left in the contact with skins. There was no increase of antioxidant capacity observed after the pressing, although the fermentation process was highly reductive and took place in closed containers.

This diploma thesis is focused on the topic The use of polyvinylpolypyrrolidone and possibilities of its regeneration in the beverage industry. The thesis was written in years 2015/2016 at the Department of Post-Harvest Technology of Horticultural Products, Faculty of Horticulture at Mendel University in Brno. The theoretical part deals with the polyphenolics compounds in wine, antioxidant capacity and wine defects related to polyphenols. The last chapter offers multiple methods of removing defects, where the highest priority is given to the clarifier PVPP. The experimental part is aimed at the regeneration of single used PVPP with four different ways and the determination of its efficiency throughout suitable analyses after its reuse in the wine. The resulting data are statistically processed and shown in the graphs.

This thesis dealing with The influence of sulfur dioxide on on qualitative parameters of the wines was developer between 2014/2016 at the Department of Post Harvest Technology of Horticultural Products, Faculty of Horticulture, Mendel University in Brno. In this thesis was studied influence of sulfur dioxide on total polyphenols, which was measured by Folin-Ciocalteu and antioxidant capacity, which was measured by FRAP and DPPH. For this experiment were chosen two wines. The white wine was Rulandské bílé and the red wine was Svatovavřinecké. Doses of sulfur dioxide were applied at 0 mg/l, 25 mg/l, 50 mg/l, 75 mg/l, 100 mg/l. These doses are used in winemaking. Was found, that sulfur dioxide added to wine influence measured values of polyphenols and antioxidant capacity measured by FRAP and DPPH. Also was found, that system FRAP is more affected by sulfur dioxide, than system DPPH.