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Vplyv stupňa oxidácie muštov na senzorické a analytické vlastnosti vín révy vinnej
Čaklošová, Katarína
This diploma thesis dealt with the influence of the degree of must oxidation on the sensory and analytical properties of wine grape. In the literary part of the thesis, chapters dealing with must, phenolic compounds, oxygen, the process of oxidation in must and wine, their effects on sensory properties and various technological methods of oxygen supply during wine production were processed. Two varieties of grapevine were used for the experiment. The aromatic category was represented by the Cvetočnij variety and the non-aromatic Grüner Veltliner variety. The musts of the two varieties were divided according to the degree of oxidation into a reductive and oxidative variant, and also according to the length of maceration to 0 and 24 hours. Oxidative variants were already hyperoxidised in the must after pressing and reductive variants were added sulfur dioxide. After pressing, all the samples were left for 24 hours by gravity sedimentation followed by spinning from the sludge and fermentation. After alcohol fermentation, the samples were coiled from coarse yeast and mixed for 4 months on fine yeast at regular intervals of 1 per week. Basic parameters, dissolved oxygen content, total polyphenols, flavanols, sulfur dioxide, optical density and color intensity were analyzed in various technological stages of production (after pressing, after sludge, on the 5th day after fermentation, after the first twisting, after 4 months). All wine samples were sensory evaluated after 4 months of maturation. The results of analytical and sensory analyzes were processed, statistically evaluated and shown in well-arranged graphs and tables. From the acquired knowledge was concluded for the purpose of its use in possible practice.
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Biologically active compounds in uncommon vegetables
VOCÍLKOVÁ, Soňa
My bachelor thesis dealed with determination of content of some phenolic compounds in some rare sorts of vegetable like Amaranthus tricolor, Chrysanthemum coronarium, Brassica rapa var. komatsuna, Brassica rapa ssp. japonica var. mizuna and mibuna, Brassica juncea. These uncommon species belonged to the asian leaf vegetable. At the present time these species are restrained over the whole world. Besides vitamins, these species of leaf vegetable contain also phenolic compounds like flavonoids, which reveal significant biological activity with positive effects on human health. The above mentioned sorts of vegetable were cultivated both on the experimental field on the open air and also in glasshouse. The content of phenolic derivatives was determined by high-performance liquid chromatography. In the selected plants were found these dominant compounds: Amaranthus tricolor contained derivatives of caffeic acid and rutin, in Chrysanthemum coronarium chlorogenic acid, dicaffeoyl acid and dicaffeoyl-succinylquinic acid. In the plants Brassica rapa var. komatsuna and Brassica juncea were determined derivatives of flavonols and phenolic acid, in varieties mizuna and mibuna derivatives of flavonols, phenolic acid and indols. Significant differences in the content of studied compounds was found between the plants cultivated under open air and in glasshouse. The plants cultivated under the open air have significantly higher content of studied compounds than those cultivated in glasshouse.
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Přehled fenolových látek v bylinných čajích
Holčíková, Dagmar
The topic of my bachelor thesis is Overview of phenolic compounds in herbal infusions. The first part of work describes the types of tea from the leaves of Chinese Tea (Camellia sinensis). The next part is focused on herbal drugs and their classification. For selected drugs are mentioned the substances and therapeutic effects. The next section describes the most important substances in herbal infusions, namely minerals, terpenes, vitamins, alkaloids, and the phenolic compounds are characterized by the most. The work deals mainly with their classifications, gives a brief description, and mentions the most famous representative of each group of phenolic compounds. The experiment determines the content of phenolic compounds and vitamin C in berries of the sea buckthorn (Hippophae rhamnoides).
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Monitoring flavonoidních látek ve vybraných druzích medu
Sojková, Tereza
This work deals with flavonoid substances contained in honey. The work is to develop a theoretical part, which is focused on the composition of honey, its effects on human health and on the description of flavonoid substances. In the next section of the work is experimental part, which is shown in tables occurrence of phenolic compounds in different types of honey.
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