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Analysis of selected nutritional parameters in the new varieties of gooseberries
Nováková, Jana ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
Diploma thesis deals with the new varieties of gooseberries. The theoretical part characterizes gooseberry from a biological point of view, what is the content of healthful nutrients and states food technology aspects. Furthermore, the theoretical part deals with the main parameters examined nutrition: vitamin C, anthokyanům and antioxidant activity. In the experimental part was measured both weight solids content and soluble solids. Vitamin C was measured by HPLC, anthocyanins using a pH differential method and for antioxidant activity determination was selected method by Kanedy known also as DPPH.
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Selected nutritional parameters of some lesser known fruit
Diblíková, Michaela ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
Diploma thesis is focused on the chemical analysis of the juices of black, red and white currant and jostaberry (Ribes a Ribes x culverwellii). The theoretical part is focused to the definition of fruit, fruit importance in human nutrition, description of Ribes and Ribes x culverwellii genuses, active substances in the currants and the jostaberry, description of selected chemical parameters and the determination of some of them. The procedures of determining for the following chemical parameters are described in the experimental section: determination of reducing sugars, determination of total and soluble solids, formol number, pH, titratable acidity, determination of total phenols and anthocyanins and determination of vitamin C in two samples jostaberry, six varieties of black currants, one variety of white currant and two varieties of red currants. Based on the evaluation of the obtained results, the comparison was made with different varieties and the thesis that "overall comparison of the different varieties in the content of phenolic compounds, vitamin C and anthocyanins appears to be the most promising variety of blackcurrant demon. It should however be noted that the highest content of phenolics and anthocyanins were determined in jostaberry„ has been suggested.
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Characterisation of elderberry fruits
Christovová, Silvia ; Diviš, Pavel (referee) ; Vítová, Eva (advisor)
This master's thesis deals with the characterization of elderberry fruit (Sambucus nigra L.) with emphasis on the aroma active compounds (AAC) and vitamin C (ascorbic acid (AA), dehydroascorbic acid (DHA)). The theoretical part gives a brief outlook on the chemical composition and attributes of Sambucus berries, its healing properties and the means of processing. The rest of the theoretical part thoroughly examines the AAC and vitamin C. The suitable assessment methods are also discussed. The experimental part of the work consists of two main tasks. The first one was to assess the aroma profile of Sambucus berries using the HS-SPME-GC-FID. 18 samples were examined (the wild elderberry and 17 cultivated varieties). In total, 24 different volatile aroma active compounds were identified and quantified, 12 of which belonged to alcohols, 5 to aldehydes, 4 to esters, 1 to acids and 2 “other” compounds (linalool and -damascenone). The chemical composition of the individual samples was not uniform; no single sample contained all of the identified compounds. The second task was to assess the total vitamin C content (the sum of DHA and AA) using the HPLC. For the purpose of reducing DHA to AA three reducing agents were examined (DTT, TCEP and L-cysteine) at two different pH levels (7 and 4). TCEP at pH 4 turned out to be most efficient and was subsequently applied on the samples of 5 selected elderberry varieties. The measured vitamin C content was within the range of 5,1 – 13,0 mg per 100 g of fruit.
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Characterisation of chokeberry and saskatoon berry fruits
Burdějová, Lenka ; Omelka, Ladislav (referee) ; Vítová, Eva (advisor)
Diploma thesis deals with the characterization of chokeberry (Aronia melanocarpa) and saskatoon berry (Amelanchier alnifolia) fruits. The theoretical part focuses on the botanical classification, chemical composition, curative effects and the use of chokeberry and saskatoon berry in the food industry. Further, the attention is also devoted to a review of methods for the determination of important antioxidants, specialized on the determination of polyphenols, anthocyanins, ascorbic acid and total antioxidant activity. The experimental part of the work deals with the determination of selected parameters in different varieties of chokeberry and serviceberry, harvested in 2012 and 2013 using spectroscopic and chromatographic techniques with an emphasis on effect of solvent (50% ethanol, destilled water, DMSO). Specifically total content of polyphenols and anthocyanins, color characteristics using the CIE L*a*b* system and the ability of the sample to reduce the iron are determined using the UV-VIS-NIR spectroscopy. Further ascorbic acid concentration in individual extracts is quantified by High performance liquid chromatography coupled with a diode array detector and the total antioxidant activity is characterized by electron paramagnetic resonance involving •DPPH and ABTS•+ assays.
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Comparison of vitamin C content between less known kinds of fruit
Mařáková, Veronika ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
This thesis deals with the determination of vitamin C in different varieties of cornelian cherry (Cornus mas) and mountain ash (Sorbus aucuparia). The theoretical part describes the botanical characteristics of both plants, the extension in the CZ and in the world, methods of reproduction, the content of meaningful health substances and the importance of both plants in food-processing industry. Attention is paid to vitamin C, which is in their fruits in high quantity. Conclusion of the theoretical part discusses various methods of determination of vitamin C. The aim of the experimental part was to comparison of the vitamin C content in different varieties cornelian cherry and mountain ash. The chosen method for the determination of vitamin C by high performance liquid chromatography (HPLC) with UV detection was first tested on standards. Selected validation parameters of this method was then determined. Validated method was used to determine the content of vitamin C in nine varieties cornelian cherry and six varieties of the mountain ash. For comparison were also tested some samples of the determination of total vitamin C after reducing dehydroascorbic acid by using dithiothreitol (DTT).
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Proposal of Marketing Mix for an Emerging Company
Hakl, David ; Chlebovský, Vít (referee) ; Havíř, David (advisor)
Bakalářská práce se zaměřuje na vytvoření marketingového mixu služby v začínající firmě. Pokládá teoretické základy pro analýzu problému, která následně představuje společnost a snaží se popsat její místo na trhu, cílovou skupinu a komplexně analyzovat situaci pro navazující část, ve které navrhuji samotný marketingový mix s pomocí metody 4P. Cílem této práce je vytvořit takový marketingový mix, který povede k celkové prosperitě služby a tím i prosperitě celé společnosti.
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Characterization of minor fruit varieties in terms of use in the food industry
Jurečková, Zuzana ; Vítová, Eva (referee) ; Golian, Jozef (referee) ; Diviš, Pavel (advisor)
The thesis deals with one group of small fruits, the genus Ribes, ie currants, and gooseberries. It assesses their physical and chemical parameters with respect to the possibility of use in these properties for the design of a new type of product – beverages. Titration, spectrometric and other methods were used for the evaluation of these properties. A total of fifteen of these methods were available (total juice yield, juice pH, total dry matter, soluble fruit dry matter, titratable acidity, formolic number, reducing carbohydrate content, D-glucose, D-fructose and sucrose content, total polyphenolic substance content, anthocyanins, vitamin C and total antioxidant capacity) and a total of nine analytes (copper, iron, magnesium, phosphorus, zinc, manganese, potassium, calcium and sodium) were selected for the determination of mineral elements. For two years (harvest 2014 and 2015), these parameters were monitored for color variants of currants (white, red and black) and gooseberries (green-fruited, yellow-fruited and red-fruited). A total of six white varieties were tested in the group of currants - Olin, Jantar, Primus, Blanka, Viktoria and Orion, eleven varieties of red currants - Junnifer, Jesan, Detvan, Rovada, Rubigo, J.V.Tets, Tatran, Losan, Kozolupský raný, Stanca, NŠLS 11/6 and eleven varieties of black currant varieties - Ometa, Démon, Triton, Ben Hope, Ruben, Ben Gairm, Ben Lomond, Moravia, Ben Conan, Fokus and Ceres. A total of five varieties of green-fruited gooseberries were tested - Zebín, Mucurines, Rixanta, Rodnik and Prima. Yellow-fruited gooseberries were available in four varieties - Lemon Giant, Invicta, Golden Fig and Darek. The red-fruited gooseberries included varieties - Rolonda, Alan, Karat, Karmen, Krasnoslawjanskij, Himnomacki Rot, Remarka, Tamara and Black Neguš. Using Tukey's test, an analysis was performed and by scoring individual varieties based on the results of individual analyzes, a list of recommended varieties was compiled for further work on the development of a new beverage. Unfortunately, in 2015 there were very few fruits of green-fruited and yellow-fruited gooseberries, so it was decided that the volume of fruit will fall on the testing of bioactive substances. Therefore, at the end of the work, it is not possible to objectively evaluate these varieties of gooseberries in the whole range of analyzes. Therefore, the point evaluation of varieties was based on the averages of individual varieties. The red-fruited varieties were available in full, and therefore a full evaluation could take place. The most significant differences between red gooseberry varieties were in the content of bioactive substances (the content of polyphenolic substances, anthocyanin dyes, and vitamin C) and antioxidant capacity. These results were provided to the food subject, which continued to work with these values. Based on this project, utility model No. PUV 2016-33171 and the resulting combined drink based on wine and fruit juice were developed.
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Preparation and use of selected nanoparticles in cosmetics
Hoová, Julie ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The Bachelor thesis is focused on preparation and use of selected nanoparticles in cosmetics. The theoretical part deals with general characterization and use of caffeine, phenolics and vitamin C in cosmetics. Further, characterization of liposomes and possibilities of encapsulation of active substances gained from natural sources were introduced. In experimental part liposomes with encapsulated active substances were prepared by three different techniques. Encapsulation efficiency was determined by HPLC/PDA, phenolics spectrophotometrically and vitamin C by titration. Prepared particles were monitored for size and stability by dynamic light scattering. Furthermore, long-term stability of liposomes in model conditions was evaluated as the amount of the active substances released during incubation. In this work was found out that from all tested samples co-encapsulated liposomes are probably the best application form which can be used in face lotion or gel. Co-encapsulated liposomes exhibited relatively high encapsulation efficiency, good stability and thanks to quality of active substances they meet customer’s requirements of cosmetic industry.
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Basic chemical characteristics of chokeberry juices
Zámorská, Vendula ; Veselá, Mária (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals wirh characteristics of berries and assessment of basic chemical parameters of chokeberry juices (Aronia melanocarpa). The theoretical part is about the basic botanical description of selected varieties of Aronia and its taxonomic status. The following are important substances contained in fruits and their part in human nutrition and use for food purposes. The end of the theoretical part of bachelor thesis is about basic methods of determining the nutritional parameters of berries. In the experimental part solids content of the fruit. Furthermore soluble dry matter content, pH, titratable acidity, formol number, reducing sacharides and ascorbic acid by spectrofotometry were determined. Based on the results, juices were compared.
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Determination of selected chemical parameters of fruits of modern gooseberry varieties
Javorská, Kateřina ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
Diploma thesis deals with determination of individual chemical parameters contained in modern varietes of gooseberries (Grossularia uva-crispa). The theoretical part is focused on the botanical characteristics of the plant, a description of selected varietes, chemical composition and food utilization fruits. The second half of the theoretical part is devoted to the characterization of selected nutritional parameters and methods for determination of total anthocyanins, phenolic compounds, vitamin C and antioxidant activity. Total of 17 varietes of gooseberries, which come from growers Vondráček and the Research and Breeding Institute of Pomology Holovousy Ltd. were analyzed in the experimental part. pH differential method was used to determination total monomeric anthocyanins. Total content of polyphenols were determined by using the Folin-Ciocalteu reagent. Next was determined content of vitamin C in all varieties by HPLC and was evaluated the total antioxidant aktivity using radical DPPH. In conclusion, individual varieties of gooseberries were compared by the contents of the determined chemical parameters.
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