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This diploma thesis was processed in the years 2018-2019 at the Institute of Horticultural Engineering of the Faculty of Horticulture of the Mendel University in Brno. The aim of this study was to verify and determine the yield of grapevine seed oil during pressing on a screw press with an emphasis on its working setting, especially on the revolutions per minute during pressing. Various possibilities of using marc and the seeds themselves were analyzed. However, we have focused on different ways of separation, seed drying technology and especially pressing methods. In the practical part were compared the results of the thousand grain weight, density of seeds, press performance and values of oil yield, as well as the content and density of oil in six selected varieties of Vitis vinifera L. Furthermore, a chapter dealing with the cost of operation was elaborated.

Nowadays the study of phenolic compounds and their content in food is of great interest due to their versatile capabilities, and above all their beneficial influence on human health. According to numerous research works phenolic compounds are able to decrease the level of cardiovascular diseases, and they have bactericidal, fungistatic, antioxidant and vitamin properties. Most authors agree that vineyard site, as a combination of soil-climatic conditions, and rootstocks have a significant influence on accumulation and distribution of phenolic compounds. That is why the influence of different vineyard site and rootstocks on content of various phenolic compounds and spectrophotometric indexes of must and wine of new interspecific grape varieties was studied. The results of our research allowed us to choose the best rootstock and vineyard site for each variety. The comparison with control varieties showed that the influence of the year on content of individual phenolic compounds is more prominent than the influence of studied factors (vineyard sites and rootstocks). The knowledge in that area could help to select and recommend certain vineyard sites and rootstocks for those varieties. The choice will be based both on the quality of must and wine and on the potentially positive influence on human health. The correlation of the antioxidant properties with the principal polyphenols showed that individual compounds are weakly associated with all antioxidant parameters, suggesting that the expression of antioxidant activity is rather a consequence of synergism between various phenolics, and it is not simply attributed to specific constituents. On the other hand a strong positive correlation of AAR in grape juice and catechin content was established, these data indicate that catechin is likely to play a major role in antioxidant activity of grapes.

This thesis was aimed at evaluating the effectiveness of the separation device for the separation of seeds from marc. The first chapter describes the characteristics of marc and how is obtained. In the second chapter, the work was focused on the possibility of using the marc in waste management and food industries. The next chapter deals with separation technology and its technical support, which describes the different technologies and processes for the separation. The work also highlights the technological capabilities of drying seeds vine after separation. The experimental part of the work is focused on the evaluation of the separation of selected varieties. This assessment is complemented by tables and graphs of the results of the experiment. In the last chapter of the thesis focuses on determining the cost of separation of seeds and draft technological lines for medium and large wine-growing operations. Technological operations are accompanied by model proposals mobile and fixed lines.

The thesis deals with testing the antimicrobial activity of the seed extracts from grapevine, in the research data summary of biologically active substances contained in the vine seed (Vitis vinifera) and brief general characteristic of selected species of microorganisms. In the practical part of thesis was examined antimicrobial effect of seed extracts obtained from grape wine varieties grown in ČR. The first part of thesis deals with the process of producing extract. It was tested nonmethanol extract exposed to oxdiation, fresh methanol and nonmethanol extract in appropriate diluted concentrations. These extracts at 100 %, 50 %, 10 % concentrations were tested by using the agar difusion method, including Escherichia coli, Enterococcus faecalis and Candida tropicalis. All tested microorganisms were inhibited by the grape seed extracts using agar well difusion method and they were cultivated in their optimal conditions for the growth and reproduction after 24 hours and 48 hours. Finally were performed measurings of the inhibition zones.

Nowadays the study of phenolic compounds and their content in food is of great interest due to their versatile capabilities, and above all their beneficial influence on human health. According to numerous research works phenolic compounds are able to decrease the level of cardiovascular diseases, and they have bactericidal, fungistatic, antioxidant and vitamin properties. Most authors agree that vineyard site, as a combination of soil-climatic conditions, and rootstocks have a significant influence on accumulation and distribution of phenolic compounds. That is why the influence of different vineyard site and rootstocks on content of various phenolic compounds and spectrophotometric indexes of must and wine of new interspecific grape varieties was studied. The results of our research allowed us to choose the best rootstock and vineyard site for each variety. The comparison with control varieties showed that the influence of the year on content of individual phenolic compounds is more prominent than the influence of studied factors (vineyard sites and rootstocks). The knowledge in that area could help to select and recommend certain vineyard sites and rootstocks for those varieties. The choice will be based both on the quality of must and wine and on the potentially positive influence on human health. The correlation of the antioxidant properties with the principal polyphenols showed that individual compounds are weakly associated with all antioxidant parameters, suggesting that the expression of antioxidant activity is rather a consequence of synergism between various phenolics, and it is not simply attributed to specific constituents. On the other hand a strong positive correlation of AAR in grape juice and catechin content was established, these data indicate that catechin is likely to play a major role in antioxidant activity of grapes.

The aim of this master thesis was to compare the effect of active dry wine yeast (ADWY), own yeast starter and spontaneous fermentation on the quality of wine produced, knowing that the fermentation is a key process in winemaking. An experiment was run with the grape varieties Veltlínske zelené and Pálava, vintage 2016, grown at University vineyards in Lednice. Racked and moderately sulfited must with optimal yeast assimilable nitrogen and sugar content was the starting point of the experiment. It was inoculated by commercial ADWY, a yeast starter prepared previously from the grapes of the same origin and the last sample was not inoculated so fermented spontaneously. Fermentation took place in the University wine cellar. Final wines were not treated by any preparate except sulfiting. Sensory and analytical analysis took place in spring 2017. The usage of self-prepared yeast starter has shown the highest sensory quality in both varieties. It has been confirmed that this old and reliable method is capable of producing high quality wines reflecting the terroir.

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ABSTRACT The diploma thesis called "Verification of efficiency and utilization of oilseed presses" is focused on the issue of oil pressing with emphasis on process efficiency and oil yield. A measurement was carried out at the Institute of Horticultural Engineering, the purpose of which was to verify the screw press of a small capacity UNO FM 3 F of Farmet, Czech Republic in the pressing of grape seed oil. The experimental measurements were carried out in 2018-2019 for seed samples provided by Agropol Mikulov, which were separated from the marc. The results of the work are divided into two main parts – Cold oil pressing and Soxhlet oil extraction and Economic aspects of wine production lines designed for seed processing and oil production. The seeds were compressed at 20, 40, 60, 80 and 100 rpm. The results confirmed that with increasing speed the pressing time was reduced. At higher speeds during compression, the amount of sediment increased. While pressing from 20 to 80 rpm, the oil yield decreased from 9.87 % to 9.67 % while the pressing capacity increased from 0.86 liter/hour to 2.17 liter/hour. It was no longer possible to press at speed 100 rpm, the machine was too overloaded. The Soxhlet extraction apparatus with hexane as solvent was used to determine the total oil content. Seed oiliness was 12.85 %. The market value of cold pressed oil from grapevine seeds, used in gastronomy or as a massage product, is 990-1100 CZK / liter. With an average crude oil yield of 8 %, from 1 ton of seeds, 80 liters of oil can be pressed, which represents the currently expected yield of 80-88 thousand. CZK. The results of the economic evaluation show that with all the costs involved in the oil production, including the investment costs for the production line, the return on investment is 3,23 years. From the results of the economic evaluation of the experiment at 9,8 %, from 1 ton of seeds the expected yield of 98 l of oil is 97 020 - 107 800 thous. CZK. The return on investment period was 1,92 years.

Jams and jellies are a significant range of fruit products and the range of products undergoing an extension due to the increase in various types of fruit used to make jams and jellies. The fruits are apples, pears, sapota, apricot, loquat, peach, papaya, plum, mango, grapes, pumpkins, etc .. This work describes a mechanism of gelation of gel substances used in the production of jams and jellies. Described herein are other additives such as sweeteners, acidity agents, flavoring agents and colorful. T What are described different recipes to production methods and packaging materials used in the manufacture of products. Described herein is a process for the production process of placing these products on the market gastronomy.