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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 basic chemical characteristics of blueberry pulp
Strapcová, Zuzana ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the investigation of selected chemical characteristics in the semifinished products of blueberries (Vaccinium myrtillus L.) and blueberries high (Vaccinium corymbosum L.). The theoretical part is described the botanical characteristics of both blueberries. The use of fruits is described in the next part. A description of the determination of the selected characteristic, refractometric of sugar dry mater, is described at the end of the theoretical part. In the experimental part, chemical characteristics were determined as total and soluble solids, pH, amount of titratable acids, reducing carbohydrates, phenolics and total anthocyanins in juice, pulp and extracts of blueberries. The purpose of the extracts was to find out how many total anthocyanins and phenolics are found in the skin of the fruit and which extract gives the highest yields. The results of the characteristics were compared across the wholefruit and semifinished products of the both blueberries. A mixture of water and ethanol in a ratio 50:50 was the most suitable solvent. The maximum extraction dependence was at twelfth and thirteenth hours of maceration. The maximum extraction dependence was determined by the above described chemical characteristics. Content of anthocyanin dyes expressed as delphinidin-3-glucoside was determined in extract of blueberry in 59,7 mg DGE100 g-1 and blueberries high in 19,6 mg DGE100 g-1. Total phenolics content expressed as gallic acid was determined in extract of blueberry in 890,9 mg GAE100 g-1 and blueberries high in 249,9 mg GAE100 g-1.
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Změny látkových složek během zrání hroznů révy vinné
Seifert, Lukáš
This Diploma thesis was focused on the study of changes in the berry components during the ripening of the grape. Four vine varieties, Pinot Blanc, Sauvignon, Grüner Veltliner, and Riesling were subjected to the investigation. Grapes were collected on four dates. The following parameters were evaluated during maturation: the weight of 10 berries, the soluble solids content, the titratable acid content and the penetration strength of the berry. From the parameters of soluble solids, titratable acids content and berry strength, the maturity index for individual varieties was calculated at the given collection date. All varieties were monitored for the development of set parameters over time and the difference between the different grape varieties. The observed varieties showed an increase in the soluble solids content during the ripening of the grapes.
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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 basic chemical characteristics of blueberry pulp
Strapcová, Zuzana ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the investigation of selected chemical characteristics in the semifinished products of blueberries (Vaccinium myrtillus L.) and blueberries high (Vaccinium corymbosum L.). The theoretical part is described the botanical characteristics of both blueberries. The use of fruits is described in the next part. A description of the determination of the selected characteristic, refractometric of sugar dry mater, is described at the end of the theoretical part. In the experimental part, chemical characteristics were determined as total and soluble solids, pH, amount of titratable acids, reducing carbohydrates, phenolics and total anthocyanins in juice, pulp and extracts of blueberries. The purpose of the extracts was to find out how many total anthocyanins and phenolics are found in the skin of the fruit and which extract gives the highest yields. The results of the characteristics were compared across the wholefruit and semifinished products of the both blueberries. A mixture of water and ethanol in a ratio 50:50 was the most suitable solvent. The maximum extraction dependence was at twelfth and thirteenth hours of maceration. The maximum extraction dependence was determined by the above described chemical characteristics. Content of anthocyanin dyes expressed as delphinidin-3-glucoside was determined in extract of blueberry in 59,7 mg DGE100 g-1 and blueberries high in 19,6 mg DGE100 g-1. Total phenolics content expressed as gallic acid was determined in extract of blueberry in 890,9 mg GAE100 g-1 and blueberries high in 249,9 mg GAE100 g-1.
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Vliv před-fermentační macerace na obsahové látky moštu révy vinné
Sapík, Miloslav
Data shows that if the year is similar to year 2013, as regards to the increased content of titratable acid, there can be a longer maceration pulp, which may serve as the future harmoniousness wine. Appropriate sufficient time of maceration for any decrease in titratable acidity corresponds to the period of maceration form 4 to 12 hours. Regarding the tartaric acid and malic acid, the time of maceration appears to be approximately 8 hours. From this time forth there may be rises in values of malic acid,which can cause microbiological instability. If we wanted to get the largest share of the health-promoting substances of this year, the must had to be macerated at least 48 hours.
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