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Modern vegetable oils useful in food and cosmetics
Plachtová, Kateřina ; Mravcová, Ludmila (referee) ; Zemanová, Jana (advisor)
The aim of this Bachelor’s thesis was to make a literary research of currently most used vegetable oils in food technology, cosmetics and pharmaceuticals focusing on health benefits, possibilities of use. Two selected modern vegetable oils were specified that are currently a subject of research in respektive fields. The selected modern oils were carrot seed oil and raspberry seed oil. A literary recherche was drawn up dealing with these oils from the perspective of their composition, charakteristics, properties and use in food technology, cosmetics and pharmaceuticals. In the experimental part of the thesis the fatty characteristics of carrot seed oil and raspberry seed oil were determined: acid value, saponification value, ester number, iodine value, peroxide value. Also fatty acids present in the oils were identified and quantified using gas chromatography with flame ionization detector. Fatty acids were analysed as their methylesters. Derivatization was was performer by alkalic esterification using methanolic solution of potassium hydroxide. In conclusion, selected oils were compared in terms of fatty characteristics and fatty acid profiles. Fatty acid composition was also compared to fatty acid composition found in literature sources.
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Evaluation of selected dietary supplements - climacterium
Tobolková, Blanka ; Vránová, Dana (referee) ; Zemanová, Jana (advisor)
A dietary supplement is a product that contains nutrients (e.g. vitamins, minerals, herbs, amino acids or fatty acids) intended to supplement the diet. The aim of the diploma thesis was to suggest a prescription for preparation of three types of dietary supplements which are used to reduce of climacteric symptoms, their production and determination of energetic (nutrition) value on account of detected content of proteins, fats and saccharides in dietary supplements. A part of the diploma thesis was to suggest suitable wrapping and price of prepared dietary supplements. The three dietary supplements were used for analyses, namely capsules, herb syrup and herb drops. The content of proteins was determined by Kjeldahl´s method, total fats were determined by Soxhlet extraction and saccharides were determined by titration with potassium permanganate (Bertrand´s method). Dietary supplements in form of capsules were particular analysed on content of heavy metals (lead, cadmium and arsenal). In herbal drops was in addition determined alcohol content (ethanol). There was from the measured data found out, dietary supplement in form of capsules was chosen as the product with the lowest energetic (nutrition) value.
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Monitoring of the influence of selected synthetic preservatives on the stability of cosmetic emulsions O/W
Holubová, Anna ; Vítová, Eva (referee) ; Zemanová, Jana (advisor)
This bachelor’s thesis collects available information on commercially supplied cosmetic preservatives Sensiva PA 20 (ingredients by INCI: phenethyl alcohol, ethylhexylglycerin), Euxyl K 900 (ingredients by INCI: benzyl alcohol, ethylhexylglycerin, tocopherol) and Euxyl PE 9010 (ingredients by INCI: phenoxyethanol, ethylhexylglycerin) from German company Schülke & Mayr, especially with regard to the assessment of their potential influence on the stability of cosmetic emulsion O/W. Subsequently, based on the literature review, selected methods were applied, their combination may prospectively serves to required evaluation of the influence on the stability of studied preservation systems.
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Use of insect flour for food and feed purposes
Árendásová, Veronika ; Zemanová, Jana (referee) ; Němcová, Andrea (advisor)
Insect meal has excellent potential as food or feed. There is a need to provide enough food for the growing population, which is linked to the increasing demand for livestock production. Meat and fish have always been the staple of the human diet as a rich source of proteins and fats for human nutrition. Fish is a good source of animal protein and fat for humans, which forms the basis of the diet of a large number of people who generally live in coastal areas. The increasing demand for fish is associated with a growing interest in high-quality and affordable fish feed. Nowadays, the main ingredient in fish feed is fishmeal, and the price is constantly increasing. The sustainability of the aquaculture industry depends on finding a substitute for fishmeal with the same nutritional value and availability. Recently, there has been a growing interest in animal protein from insects for fish fattening. This thesis focused on analysing insect meal from mealworm larvae (Tenebrio molitor) and its use for food and feed purposes. The theoretical part describes the mealworm, the use of insect meal for human nutrition, and fish fattening. It also describes the requirements of fish for individual nutrients and the characterisation of insects for feeding purposes, focusing on the mealworm used as an alternative feed ingredient in fish. The individual major nutrients, namely protein, lipids, fatty acids, amino acids, fibre, chitin, and selected minerals, were determined in the experimental part. The experimental part was divided into two parts, and the first part was divided into two phases. The first phase was used to determine the nutritional components in two fractions of insect meal from Tenebrio molitor larvae. The first fraction contained the fine fraction, and the second fraction the coarse fraction of insect meal. In the second phase, the content of nutritionally significant components was only determined in the insect meal from dried larvae without fractionation. A fish feed was designed from the analyses results. In the second part, the effect of the addition of insect meal from Tenebrio molitor for food purposes was investigated; specifically, the sensory properties of muffins were monitored. From the results, it can be observed that the nutritional composition of the insect meal suggests the possibility of using the mealworm larvae as an ingredient in the fish diet. The insect meal contains a high proportion of valuable proteins and lipids necessary for fish farming and a low proportion of carbohydrates, which unlike humans, fish do not need in their diet. The sensory analysis results indicate that consumers are not prepared to eat foods with added insects.
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Influence of selected active compounds for properties of gel and emulsion cosmetics
Gardoňová, Lenka ; Pekař, Miloslav (referee) ; Zemanová, Jana (advisor)
This master‘s thesis studies problems of chosen active substances in cosmetic emulsions and gels. There is their main characteristics – distribution and properties of cosmetic emulsions and gels, preparation of the active substances, effects on the skin and conditions, which could them influence. In experimental part, preparation of gels and emulsions bases was described which were than enriched by active substances - evening primrose oil, hemp oil, Salvia officinalis extract, Symphytum officinale extract and sea salt. Properties of these cosmetic gels and emulsions bases with the addition of active substances depend on temperature and method of storage, amount of light exposure, method of preparation and another conditions. Action of these factors can cause changes of the stability, thereby the cosmetics effects on the skin can be lost. On the bases of performed rheology measurements (oscillation and flow measurements), pH measurements and sensory analysis were determined, if the properties of examined samples were changed. The measurement was performed in the certain time intervals and the properties were evaluated like at laboratory temperature 23±2 °C, so after exposure to temperature regime 37 °C in thermoregulator. On the basis of performed measurements, there was determined, that gel base with addition of Symphytum officinale extract had the most stability properties.
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Cheese curd parameters influence to selected economic factors of production of cheese with white fungus
Pavlíčková, Žaneta ; Zemanová, Jana (referee) ; Babák, Libor (advisor)
The theme of this diploma thesis is the monitoring of influences on economic aspect of the production of the blue cheese "Hermelín" in the company Pribina. The objective was to specify the dependencies of the deviations of the features of productive cow's milk and of cheese curd made from it and their economics impacts. For this purpose, the analyses of curd grain, whey and cheeses just formed were executed. The samples were taken and analyzed during the manufacturing of cheeses in the factory. Another goal was to try to design a quick operational method for measuring the firmness of curd grain, which is a factor theoretically dependent on renneting qualities of milk and indicating losses of valuable components from cheese curd to whey. The firmness of grain along with these losses may cause negative deviations from required standard of final products, especially at parametres needed for entry of cheeses on sale, such as total solids, weight or content of fat. Concerning productive pasteurize milk, the most attention was focused on the milk coagulation time and its influence on successive phases of manufacturing and on final product. Milk coagulation time is an essential technological quality of milk and it is participant on quantitative and qualitative production of cheese factory. It has been proved that milk coagulation time is notably affected by its titrating acidity, statistic analyse found this influence as very statistically significant (P
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Less conventional botanical sources of cosmetic raw materials
Novotná, Petra ; Vespalcová, Milena (referee) ; Zemanová, Jana (advisor)
The aim of this bachelor’s thesis is an investigation of use of less traditional plant sources in cosmetic industry. This review is focused on black elder (Sambucus nigra), sea buckthorn (Hippophae rhamnoides), quince (Cydonia oblonga), dog rose (Rosa canina), and stinging nettle (Urtica dioica). The substances Isolated from these plants can be used in various cosmetic products. The first section of this search deals with history and botanical characterization of these plants. The next section deals with significant substances contained in these plants and their use not only in cosmetic industry.
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Extraction of anthocyanin pigments from black chokeberry pomace
Martinková, Patrícia ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
The diploma thesis deals with the preparation of extract and concentrate of anthocyanin dyes from aronia moldings (Aronia melanocarpa). It also determines chemical properties important for human´s health, which are important also for further possible use of extract/concentrate as natural red food coloring. A series of extractions of dried and powdered aronia moldings was carried out in the experimental part of the thesis, aiming for the optimization the conditions of the extraction. Extracts were characterized by content of total anthocyans, content of total fenolic substances and total antioxidant activity. The best laboratory conditions for extraction were determined as follows: amount of moldings 12,5 g, composition of extraction agent ethanol:water 1:1, volume of extraction mixture 60 ml and time of the extraction 11 hours. Prepared extracts were concentrated on vacuum evaporator. It has been found that the temperature of the water bath in the vacuum evaporator can not exceed 40 °C. At higher temperatures there is significant degradation of anthocyanins. Furthemore, the content of individual anthocyanic dyes in extract and concentrate, from aronia moldings, was quantified by HPLC. The major anthocyanin, cyanidine-3-galactoside, was contained in the concentrate at 923,6 ± 8,5 mg·l-1, the other specified anthocyanin, minor cyanidine-3-glucoside, was present at a concentration of 53,5 ± 0,3 mg·l-1.
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Diurnal changes of Rubisco content and its activity under ambient and elevated concentrations of carbon dioxide
Matulková, Zuzana ; Zemanová, Jana (referee) ; Hrstka, Miroslav (advisor)
In this diploma thesis, the diurnal changes of initial and total Rubisco activity and Rubisco enzyme content in beech (Fagus sylvatica) were studied under conditions of ambient (A) CO2 concentration (350 µmol.mol-1) and elevated (E) CO2 concentration (700 µmol.mol-1) during the day. Samples were taken on July 8th (from 10:00 to 21:30), on July 9th (from 04:00 to 12:00) and then on July 22th (from 04:00 to 21:30). The initial and total activity were measured spectrophotometrically and the activation level was calculated from the ratio of initial and total activities. Rubisco enzyme content was determined by SDS-PAGE method and the initial and total specific activity were calculated from the ratio of initial or total activity and Rubisco enzyme content. In our experiment no statistically significant difference was found between Rubisco activities in beeches cultivated under conditions of ambient CO2 concentration and elevated CO2 concentration, so any down-regulation of Rubisco activity did not appear under the influence of ambient CO2 concentration. Diurnal changes of Rubisco activities showed only statistically nonsignificant fluctuation. After daylight no significant increase of total Rubisco activity was observed, which demonstrates the absence or the immaterial effect of CA1P night inhibitor in beech. Intensive fluctuation of the activation level (40–90 %) proves the regulation of photosynthesis during the day via Rubisco enzyme carbamylation. Rubisco enzyme content in beech cultivated under conditions of ambient CO2 concentration was lower than that one in beech cultivated under conditions of elevated CO2 concentration. Then down-regulation of Rubisco enzyme content is presented under conditions of ambient CO2 concentration. Before daylight Rubisco enzyme content showed an indistinctive minimum on the level of statistical significance, during the day only nonrelevant fluctuation was noticed.
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Study of macerates of selected plant materials in oily bases
Masár, Martin ; Pořízka, Jaromír (referee) ; Zemanová, Jana (advisor)
The aim of this thesis was in terms of literary research describe the composition, production, impact on human health and diverse uses of vegetable oils and their herbal macerates in human life. Herbal oil macerates are actually a blend of oils and herbs, created to produce a product that combines the beneficial effects of oils with therapeutic effects of herbs. Avocado and almond oil were used in combination with herbs such as black elder, chinese tea tree and ginger. Each herb also affects to some extent the quality of oil, which was observed in the time dependence of acid number in herbal macerates compared to pure oils. The acidity of the oil is also significantly influenced by temperature and therefore one set of samples was macerated at room temperature and the other in a thermostate at 35°C. The time dependencies of the acidity number of the individual oils and macerates were plotted into graphs and compared. In most cases, the thermostate-stored oils and macerates obtained higher acidity than those stored at room temperature. The effect of the herbs on the acidity of the oil varied in the different types of macerates, with the highest acidity values being taken by macerates with black elder flowers and the lowest, most similar to pure oils, by macerates with black elder fruits. At the end of the experiment, total and free fatty acids from the last sampling (after 77 days of extraction) of macerates and oils at room temperature were analysed by gas chromatography. Again, there were some differences in the composition of total and free fatty acids in herbal macerates compared to pure oils. Some herbs affect the composition of individual fatty acids more, others do not affect it almost at all.
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