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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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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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Determination of macroelements, organic acids and other parameters in ketchups
Popelová, Nikola ; Divišová, Radka (referee) ; Diviš, Pavel (advisor)
The aim of this master’s thesis is perform basic analyses of samples ketchups. The theoretical part describes the basic characteristics of tomato, tomatoes processing and production of puree and ketchup. Then there are described analytical methods which were used for analysing the selected parameters in ketchups. The experimental part deals with the determination of pH, total solids, organic acids, saccharides, macroelements and lycopene in ketchups. Citrate and acetate were analysed by IC. The amount of acetate in ketchups was about 5 times greater than the amount of citrate. Glucose, fructose and sucrose were analysed by HPLC. Glucose and fructose were determined in all samples but sucrose not. The ICP-OES method was used to determine four elements. Magnesium was the least represented element and sodium was the most represented element in the analysis. The amount of sodium was recalculated on the amount of salt. Lycopene was analysed by UV-VIS spectrometry. Its amount in ketchups is influenced by the variety of used tomatoes and plenty of other factors.
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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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The basic chemical parameters of several varieties of sour cherries
Komárek, Šimon ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis deals with determination of basic chemical parameters in sour cherry (Prunus cerasus). Three different cultivars Köröšská, Pandy 6039 and Šumadinka were examined. The content of total solids varied from 13,32 to 15,22 %, soluble solid content amounted for 12,04–14,60 %, ash 0,4 %, reducing sugars 4,9–6,9 %, nitrogenous substances 0,11–0,12 %, L-ascorbic acid 343–456 mg/kg. Titratable acidity ranged from 15,1 to 21,8 g malic acid equivalent/kg, formol number 268–373 ml of 0,1 NaOH/kg. Total anthocyanins varied from 308 to 1104 mg cyanidin 3-glucoside equivalent/kg and total phenolics ranged from 1,05 to 3,99 g gallic acid equivalent/kg. All data are applied to fresh fruit weight.
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Chemical characteristics of fruit Mirabelle plum
Lukšová, Leona ; Pořízka, Jaromír (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with chemical and physical analysis of dried, lyophilized and stewed fruit, specially Mirabelle de Nancy. Theoretical part is devoted to the origin, the economic importance of plums, the botanical classification of Mirabelle de Nancy and other subspecies belonging to the genus Prunus. Subsequently the most economical method of preserving food called lyophilization is described. Part of this work is also the theme of raw food and description of biologically active substances contained in this fruit. In the experimental part, these characteristics of Mirabelle de Nancy were analyzed: total solids, soluble solids, determination of reducing sugars, titratable acidity, phenolic substances and ascorbic acid. It has been found that the lyophilized friut contains 16,8 wt. % of reducing sugars which is less than dried fruit with a value of 18,0; wt. %. It also contains less titratable acids with a value of 59,7 mmol/l versus 72,7 mmol/l in dried fruit.
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Basic chemical characteristics of cranberry juice
Cao, Ha Thuy ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis is about lingonberries and cranberries. It is mainly about berries which were used for chemical analysis. The berries are from the Research and Breeding Institute of Pomology Holovousy Ltd. and they have delivered six cultivars of lingonberries and three cultivars of cranberries. There is a research of general information about classification, botanical description, important chemical substances such as vitamins, natural colorants and products made in the industry. Furthermore there is descriprion of chemical methods for basic analysis. The next part of bachelor thesis is about how all these methods were applied to berry juice. What instruments and chemicals were used. First assessment was profit of juice which was about 50,00–60,00 %, but lingonberry Runo bilawskie has at least 31,49 % and cranberries have less profit too. Total solids were determined in the range of 11,40 % (Pilgrim) to 18,50 % (Runo bielawskie) and solitable solids are in range of 10,00 % (Pilgrim) to 16,08 % (Korál). Lingonberry contains more reducing sugars (8,81–12,92 %) than cranberry (7,90–9,03 %). Titratable acids are about 32,04–49,60 mmol.l-1 for lingonberry and about 55,40–60,67 mmol.l-1 for cranberry. The measurements show that pH of both berries are about 3. The most phenolic substances are found in range of 2187,11–3476,75 mg.l-1. Berries content anthocyans colorants in range of 54,91-65,29 mg.l-1 and the most in cranberry. All results are shown in charts and in the end there is a discussion and conclusion about methods and results.
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Basic chemical properties of fruits of selected cherry varieties
Chmil, Vojtěch ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
Diploma thesis is focused on chemical characteristics of nine selected sweet cherry varieties in nine parameters. Total and soluble solids were analyzed with these results 13.07–16.58 % for total and 14.67–19.50 °Brix for soluble solids, ash content 0,31–0,39 %, titratable acidity 5.44–9.91 g of malic acid per 1 kg of fresh cherries and formol number 14.45–23.73 ml of 0.1 M NaOH per 100 g of cherries. Then there were analyzed crude proteins content calculated from total nitrogen content determined by Kjeldahl method with results 0.41–0.68 % of crude proteins. Molecular absorption UV/VIS spectrophotometry was used for determination of total phenolic substances 0.30–0.89 g of gallic acid per 1 kg of cherries and total content of anthocyanins 128–848 mg of cyanidine-3-glucoside in 1 kg of cherries. Saccharides were determined by high performance liquid chromatography (HPLC) with ELSD detector. Content of glucose was 45.45–59.49 g/kg and fructose 46.88–60.01 g/kg. All results are compiled using tables and graphs and discussed. Experimental part of the thesis also describes principles and procedures of every analysis, so it can be reproduced. In theoretical part there is described botanical characteristic of cherry tree (Prunus avium L.), active substances contained in its fruits and their use in food industry. At the end of the theoretical part there is described instrumentation of high-performance liquid chromatography.
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Monitoring of the selected parameters of grape wine before expedition
Trávníčková, Jiřina ; Pořízka, Jaromír (referee) ; Omelková, Jiřina (advisor)
Presented bachelor thesis is focused on laboratory monitoring and determination of the selected parameters of grape wine which includes specific gravity, alcoholic content, reducing sugar content, total titratable acidity, volatile acidity and total solids, sulfur dioxide content and protein and crystalline wine stability. The theoretical part deals with the wine production technology from the entry commodities to the bottling of mature wine. The aim of experimental part is a description of analytical determinations and complete wine sample analysis according to Regulation EEC No 2676/90 determining Community methods for the analysis of wines.
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Measurement of selected physical properties of the waste water from biogas plant
Ondruška, Vojtěch ; Zejda, Vojtěch (referee) ; Vondra, Marek (advisor)
The aim of this Bachelor’s thesis is the experimental measurement of physical and chemical properties of the wastewater from biogas plants. Thesis concisely describes wastewater and its origin. The main part is dedicated to the design of experiments and to the detailed description of the measurement of selected properties with the available laboratory methods. Measured data are evaluated and compared to literature. The results of this thesis can be employed to further develop the equipment for thickening wastewater from biogas plants or to other scientific activity in the field of waste management in agriculture.
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