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Beer foam stabilization using biosurfactants
Jandrtová, Sabina ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis focuses on a research of the foam stability of the beer. We specifically observed the influence of ethanol and surface tension on the foam stability, and influence of ethanol and surface tension on the height of the foam. It was observed the influence of the hop acids in non-alcoholic beers. Furthermore, different biosurfactants were added into to the beer to observe better stability of the foam. The theoretical part of this work describes the foam from the physical aspect. There are described fourth key events involved in foam formation. Then it focuses on the beer foam – its structure, substances that influence its behavior and measurement of the foam stability. In this part there are described biosurfactants as well – their characteristics, qualities, distribution and applications. The experimental part is dedicated to the influence of ethanol, surface tension, the amount of iso- acids on foam stability in beer. There is observed the influence of biosurfactants of the foam stability and surface tension, which are added into to the beer. For the measurement of the foam stability was used the Rudin method. Liquid chromatography with DAD detector was used for the measurement the amount of the hop acids. The surface tension was determined by tensiometer. According to the results addition of ethanol changed the characteristics of the foam stability, but it’s not easy to find correlation between the increasing amount of ethanol and its stability. It was found out, that there is connection between the amount of ethanol and surface tension. On the other hand, there is not much connection between the surface tension and foam height. Within the framework of addition of biosurfactants was observed, that these foaming agents interacted the surface tension of the beer (lowering), however these agents accelerated the fall of the beer foam.
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Obsahové látky jedlých květů a jejich antioxidační aktivita
Tvrzníková, Eliška
This diploma thesis deals with phytochemicals with antioxidant effect in edible flowers. In the literary section are described edible flowers, antioxidants and substances harmful to human health. In the selected assortment is described the morphology of the flower, the origin, the distribution, the occurrence, the demands, the use and the multiplication according to whether they are species growing in the wild or cultivated species are described. In the practical part, flowers were harvested from March to May 2017 and their content was determined - vitamin C, flavonoids, phenols, saponins, antioxidants. This thesis confirmed that phenolic substances are primarily responsible for the antioxidant capacity. The highest antioxidant capacity along with phenolic substances was in the flowers of Bergenia ciliata.
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Vliv technologie pěstování kotvičníku zemního (Tribulus terrestris L.) na kvalitu produktu
NEUMANN, Jaroslav
This diploma thesis focuses on the Tribulus terrestris and its cultivation in order to achieve the highest content of biologically active substances. Tribulus has its roots in Chinese traditional medicine and Indian Ayurveda. The monitored substances are protodioscin and diosgenin. These two substances are saponins which are known for many beneficial effects on human health. For example, protodioscin is widely used as a remedy for conception problems. Diosgenin has its use in the fight against cancer. Both of these substances are also used in fitness to increase muscle mass and strength. The most famous is protodioscin, which became famous thanks to the Bulgarian weightlifters. However, the mechanisms of action of protodioscin and, in fact, diosgenin in the human body are not completely known in terms of influencing hormones in our body. In the practical part of this work, acetylsalicylic acid and the commercial preparation NanoFyt Si? are used as an elicitor. Water control was used for control, which was carried out in the same way as elicitor sprays. It is statistically summarized in what concentration the elicitors act or do not act. Based on statistical results, the cultivation procedure is recommended.
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Využití merlíku chilského - quinoa (Chenopodium quinoa Willd.) v potravinářství
Křivánková, Kateřina
Bachelor thesis "The use of chilean merlot - quinoa (Chenopodium quinoa Wild) in food industry" deals about its history, cultivating, variety and contained substances. Next, there are described diverse ways of using quinoa in food industry and its positive effects at health. Thanks to the high nutritious value, quinoa is called superfood, which NASA investigate as a suitable food for astronauts. Bitter saponins also contained in seeds make problems, they are needed to be removed before using. Quinoa comes from the South America, but it is possible to grow it in the Czech Republic, too. The most suitable is the Danish variety TITICACA. In a practical part of this thesis, the research of market in shops of „health nutrition“ is evaluated. It has been accomplished by means of questionnaires, which were filled by owners of inquired salesrooms. There are offered red, white and black seeds in a market. The white seeds are the most salable. It is possible also to buy flakes, flour and next products containing quinoa.
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Beer foam stabilization using biosurfactants
Jandrtová, Sabina ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis focuses on a research of the foam stability of the beer. We specifically observed the influence of ethanol and surface tension on the foam stability, and influence of ethanol and surface tension on the height of the foam. It was observed the influence of the hop acids in non-alcoholic beers. Furthermore, different biosurfactants were added into to the beer to observe better stability of the foam. The theoretical part of this work describes the foam from the physical aspect. There are described fourth key events involved in foam formation. Then it focuses on the beer foam – its structure, substances that influence its behavior and measurement of the foam stability. In this part there are described biosurfactants as well – their characteristics, qualities, distribution and applications. The experimental part is dedicated to the influence of ethanol, surface tension, the amount of iso- acids on foam stability in beer. There is observed the influence of biosurfactants of the foam stability and surface tension, which are added into to the beer. For the measurement of the foam stability was used the Rudin method. Liquid chromatography with DAD detector was used for the measurement the amount of the hop acids. The surface tension was determined by tensiometer. According to the results addition of ethanol changed the characteristics of the foam stability, but it’s not easy to find correlation between the increasing amount of ethanol and its stability. It was found out, that there is connection between the amount of ethanol and surface tension. On the other hand, there is not much connection between the surface tension and foam height. Within the framework of addition of biosurfactants was observed, that these foaming agents interacted the surface tension of the beer (lowering), however these agents accelerated the fall of the beer foam.
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Technologie pěstování Kotvičníku zemního (Tribulus terrestris L.) a jeho využití
NEUMANN, Jaroslav
This bachelor thesis is about a plant named Puncturevine (Tribulus terrestris), its substances, which are contained and about its possible usage in medicine. Another chapters describes some substances which we can find in a whole plant. The most important substances are saponins, phytosterols and flavonoids. Saponins are most popular for their aphrodisiatic effects, flavonoids for fighting illnes and phytosterols for decreasing cholesterol in blood plasma. Quantity of these substances is highly dependent on the area where, or how the plant is grown and if elicitors were used. In the practical part I found out if tribulus is known amongst people and how to grow it in greenhouse.
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Změny v kvalitě měsíčkové drogy
Lekeš, Radek
On the base of charakterization using organs of mangold was attention focus on posibilities to influence substances in inflorescence, whose application is not relate just to terapeutic effects. Every group of substances has diferent curative properties, while in plant material affect complex of substances and some of them are more important than others. These are very sensitive to every patological change in plant or in harvested drug. Degradation of these substancies is posible to prevent by, more ways, which have to be in harmony with law. These motheds and proceses are aplicated on the base of knowledges about influence factors. Varieties, rezistence etc., are include in internal factors. Between external factors belong fertilization, or patogens.
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Growing technology earthy Tribulus terrestris (Tribulus terrestris L.) and its use
HUDSKÁ, Miluše
This bachelor thesis deals with Puncturevine (Tribulus terrestris) as for planting, content substances, pharmacological use and with influences of planting technology or elicitors upon the active substance contents. Saponines, flavonoids, and phytosterols are the main active substances of Puncturevine. The saponines act as aphrodisiacs, the flavonoids treat with heart diseases and the phytosterols decrease the cholesterol concentration in blood plasma. The active substance contents depend on the planting and elicitor influences. The practical part is focused on the matters of free soil growing and economy of planting the herb.
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