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Basic chemical characteristics of juices of selected white gooseberry varieties
Zelníčková, Jaroslava ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Theoretical part of this bachelor thesis includes taxonomical classification of gooseberry, deals with biological characteristics, active substances contained in fruits of gooseberry and its using as well with description of the methods by research detection. In the experimental part primary nutritional parameters of chosen gooseberry species were analysed including orientation juice yield, soluble solids, pH, dry matter, titratable acids, formol number and reducing sugars. There were analysed following species of gooseberry: Reflamba, Mucurines, Rixanta, Veliš, Citronový obří, Darek, Prima, Invicta, Zlatý fík a Zebín. Individual species and cultivars were compared based on the results.
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Basic chemical characteristics of juices from selected blackcurrant varieties
Maňásková, Eva ; Pořízka, Jaromír (referee) ; Vespalcová, Milena (advisor)
This thesis deals with the basic characteristic of juices of the selected varieties of blackcurrant. The theoretical part presents the history and origin of this fruit cultivation, basic botanical description of each species and selected varieties and also features active substances contained in fruits. Conclusion the theoretical part then describes procedures basic methods of determining the various chemical parameters of fruits. In the experimental part was set tentative determination juice yield, soluble solids content, pH, titratable acidity and formol number. Based on the results were different varieties compared.
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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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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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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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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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Fyzikálně chemické změny hroznů révy vinné během zrání
Majorová, Anežka
This diploma thesis deals with the physical changes of grapevines during their ripening. Three grapevine cultivars were tested - Hibernal, Malverina and Perun. Grapes were harvested at three different times and the basic criteria for defining the level of ripeness were observed namely, in particular, the weight of bunch of grapes, the weight of ten vine berries, grape berry firmness, the percentage of dry matter and the percentage of titratable acids, and the ripeness index. The changes of all criteria in time as well as the difference between particular cultivars were observed. Furthermore, the correlation between criteria was assessed. The grape berries were also assessed from the visual point of view before harvesting. Regarding all the data which was collected, the decrease of titratable acids for each grapevine cultivar was proven during the monitored period. For Hibernal, a linear decrease of 26mg/100g per day was observed. Linear decrease was also observed for grape berry firmness of 18 kPa in case of Hibernal, and 24 kPa in case of Malverina. Increase of the percentage of dry matter was observed for all three cultivars. In addition, a correlation between the weight of a grape berry and any other measured criteria was not found. The ripeness index shows a different beginning of ripening of different cultivars.
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