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Determination of selected nutritional parameters in the fruit of the plant genus Ribes
Ledvina, Vojtěch ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis focuses on the small fruit representatives from the plant genus Ribes L. - currant, gooseberry and jostaberry. The beginning of theoretical part describes history of cultivation and basic botanical description of individual cultivars. The next part describes important substances contained in fruit as well as their importance in human diet and it also describes some basic products made of the Ribes L. genus representatives. The final section of the theoretical part contains basic principal of determination of individual nutritional parameters. In the experimental part several nutritional parameters were determined including dry matter, soluble solids, pH, titratable acids, formol number, reducing sugars and total phenolics. Individual species and cultivars were compared based on the results.
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Determination of basic chemical characteristics of blackberry pulp
Pilátová, Anna ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with determination of selected chemical characteristics of juice, pulp and extract prepared from blackberry of two species, from The Czech Republic and Ukraine. The theoretical part contains the botanical characteristics of blackberry, the content of active substances and possibilities of use of blackberries in the food industry. The following chapters focus on the description of phenolic substances and the determination of pH and titration acidity of fruit juices by manual methods. In the experimental part, two extraction solvents were first compared for extraction of anthocyanins from blackberry moldings. Furthermore, the selected chemical and physical properties of extracts, juice and pulp from blackberries were determined. The analysis was carried out for blackberries from the Czech Republic and Ukraine. A 1 : 1 mixture of distilled water and ethanol was a better extraction solvent for the content of anthocyanins. After 14 hours of maceration 150.4 mg of anthocyanins was obtained from 100,0 g of blackberry moldings Extract from blackberry moldings has been determined to have a much higher concentration of anthocyanins than juice and pulp. The extract of Ukrainian blackberries contained 197.4 mg CGEdm-3 and extract of Czech blackberries 150.4 mg CGEdm-3. Also phenolic substances had the highest concentration in extracts. Ukrainian blackberries contained 3501.9 mg GAEdm-3 and Czech blackberries contained 3256.1 mg GAEdm-3.
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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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The measurement of total alkaloids in tobacco
Pipková, Renata ; Vránová, Dana (referee) ; Omelková, Jiřina (advisor)
The aim of this diploma thesis is the assay of total alkaloids in different tobacco types. To measure the content of total alkaloids are utilized types of tobacco used for preparation of tobacco blends and consecutive production of cigarettes. The samples of analyzed tobacco include various countries of cultivation and different crop years. There is described tobacco as a plant, in it contained alkaloids and the utilization of tobacco in the theoretical part. In more detail it deals with the production and construction of cigarettes which is closely related to the content monitoring of total alkaloids in tobacco. The contents of total alkaloids are determined by the continuous flow analyzer- SKALAR. On this spectrophotometer are set the contens of reducing sugars as well. The comparison of total alkaloids contents and reducing sugars from the perspective of single tobacco types, countries of cultivation and crop years is clearly summarized in the experimental part of the thesis that was performed in the company Philip Morris ČR, a.s.
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Extraction of bioactive substances from the pomace of red grapes
Jandrtová, Sabina ; Pořízka, Jaromír (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the research of chosen chemical characteristics in juice and in extracts of grapevine (Vitis vinifera L.). The theoretical part is divided into three parts. In the first part is described the botanical characteristic of grapevine, then its origin, morphology, chemical composition, species and uses. In the second part are characterized anthocyanin pigments, their occurrence and attributes. There are described methods of the investigation. In the third part are described extractions. The experimental part illustrates extractions of the pomace. The purpose of these extractions is to find out the total amount of anthocyanins and phenolics in the pomace, and which solvent gives the highest yield. Then the chemical characteristics, such as total and soluble solids, pH, the amount of titratable acids, reducing carbohydrates, phenolics and anthocyanins, are described in this section. All determinations are executed and results are compared among grapevine juice and two species (Cabernet Sauvignon and Zweigeltrebe). The most suitable solvent is selected a mixture of water and ethanol in a ratio 50:50. In the most effective hours are determined the chemical characteristics. The titratable acids are expressed as the amount of the tartaric acid. The amount of phenolics is expressed as gallic acid and the amount of anthocyanins as malvidin-3-glucoside.
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Extraction of bioactive substances from black currant pomace
Sedláčková, Lucie ; Štursa, Václav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with extraction of bioactive substances from black currant pomace (Ribes nigrum). The theoretical part contains the botanical characteristics of the plant species Ribes nigrum. It is also devoted to the biologically active substances contained in black currant and possibilities of using black currant in the food industry. The fourth chapter deals with description of phenolic compounds, their distribution and methods of determination of phenolic substances. The fifth chapter describes selected extraction procedures. In the experimental part, there were extracted dry black currant pomace in order to optimize the extraction process and obtain the highest yields of dyes. In addition, were determined the selected chemical and physical characteristics of blackcurrant juice and extracts from blackcurrant pomace. A better solvent was a mixture of water and ethanol in a volume ratio of 1:1. After 14 hours maceration of dry pomace, were obtained 769,9 mg anthocyanins per 100 g of dry material.
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Basic chemical characteristics of juices from selected red currants varieties
Rucká, Markéta ; Jurečková, Zuzana (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis is focused on the determination of basic chemical characteristics of selected red currants varieties from the Research and Breeding Institute of Pomology Holovousy Ltd. The theoretical part concentrates on general information about red currant, such as history of cultivation, origin and its expansion. There is also mention of the general characteristics of currant, currant building and significance of red currant cultivation. Chapter "Individual varieties" deals with the analysed varieties of red currants, especially its description and its biological properties, followed by an overview of the main substances contained in red currants and their brief description. Bachelor thesis also presents examples of the processing and the utilization of red currant in the food industry. The final chapter provides information about the individual determinations of the chemical characteristics of red currants, which include juice yield, soluble solids content, total dry matter content, pH, titratable acidity, formol number and reducing sugars. The experimental part describes the specific conditions and methods of individual determinations, followed by a summary of the results and their discussion. Variety Jesan showed the highest juice yield (63 ml per 100 g) and the highest pH value (3,16). The highest soluble solids content (13,94 %) and the highest formol number (22,83 ml of 0,1 M NaOH per 100 g) was determined in a variety Jonkheer van Tets. The highest dry matter value was detected for variety Rovada (14,48 %). The titratable acids content was highest in variety NŠLS 11/6 (403,88 mmol•kg-1). The highest concentration of reducing sugars was found in variety Tatran (8,17 %).
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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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The basic chemical parameters of several varieties of cherries
Boberová, Jana ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis deals with determination of basic chemical parameters in sweet cherry (Prunus avium). In the theoretical part, the taxonomic classification of the cherry, its botanical characteristics and the pomology of several cultivars are mentioned. Also, the history of cultivation, appropriate conditions and most common diseases are listed. The last chapter deals with the chemical composition of the fruits. In the experimental part, the determination of selected chemical parameters of various cultivars (Karešova, Napoleonova and Stark Gold) were determined. The content of total solids was determined in the range of 14.53–18.15 %, soluble solids 13.96–16.44 %, ash 0.34–0.44 %, reducing sugars 6.89–10.18 % and nitrogenous substances 0.056–0.116 %. Ascorbic acid content was set at 26.1–44.1 mg/kg. The titratable acidity was determined in the range of 6.15–8.86 g of predominant malic acid in 1 kg of cherry and a formol number was determined from 194 to 297 ml of 0.1 M NaOH per 1 kg of edible fraction. The amount of anthocyanins was determined at 4–686 mg cyanidin-3-rutinoside/kg and total phenolic compounds at 0.91–1.47 g gallic acid/kg. All data are based on fresh fruit weight.
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