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Chemical and sensory analysis of fruit juice from selected cultivars of European elder
Ješková, Kristýna ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
The aim of this thesis is the chemical and sensory analysis of the juice from fruits of cultivated varieties of elderberry (Sambucus nigra L.). In the theoretical part botanical description of elderberry including its distribution and places of existence are given. There are also mentioned medical effects and collection of various parts of the elderberry as well as breeding certain species and methods evaluating sensory features of the juice samples prepared from the cultivated varieties of elderberry. In the experimental part some chemical parameters (yield, soluble dry matter content, relative density, pH, titratable acidity, formol number, reducing saccharides) in the juice of berries of eighteen cultivated varieties of elderberry were determined. In fifteen cultivated varieties was made sensory evaluation using profile test and scale. The aim of the evaluators in the evaluation using scale was to evaluate the taste, smell, sensory quality and preferences according to seven point cathegorical hedonic scale. In the profile test, five point scale was used to evaluate the intensity of chosen flavours: acidic, sweet, bitter and others. Overall impression of the sensory evaluation was rather not positive. In majority of the samples the taste and smell were evaluated as good or satisfactory and their general acceptability, too. The juice from the wild elderberry was estimated as worse than in other samples, its taste, smell and overall acceptability were unsatisfactory. In majority of the cultivated varieties were the taste and smell estimated as unsatisfactory as well as their general acceptability.
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The chosen validation parameters of method for assessment of aroma compounds in elderberries
Christovová, Silvia ; Ürgeová, Eva (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the assessment of aroma active compounds in elderberries (Sambucus nigra L.). In the theoretical part the chemical composition and attributes of elderberries are described. Brief information on their healing properties is also given. The possible processing methods in food industry, as well as the traditional means of use at home, are discussed furthermore. Following chapters describe the gas chromatography method combined with the technique of solid-phase microextraction, utilized for the specification of aroma active compounds. The validation of this method is also included. The aim of the experimental part of the work was to verify a set of the selected validation parameters of the SPME-GC method, specifically linearity, the limits of detection (LOD), the limits of quantification (LOQ) and repeatability. Subsequently, the SPME-GC method was applied on the chosen elderberry juice samples. In total, 37 different volatile aroma active compounds were identified and quantified, 15 of which belonged to alcohols, 9 to aldehydes, 5 to ketones, 5 to esters and 2 other compounds. The chemical composition of individual samples was not uniform; no single sample contained all of the identified compounds.
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Assessment of aroma active compounds in elderberries
Kaňová, Kateřina ; Divišová, Radka (referee) ; Vítová, Eva (advisor)
This work is focused on determination of aroma compounds of elderberries (Sambucus nigra L.). The theoretical part provides an overview of the properties, occurrence, other varieties and composition of elder berries and their use particular in the production of juices. The possibilities of assessment of aroma compounds are also briefly discussed. In the experimental part, the identification and quantification of aroma compounds in samples of mixed juices (elder with grape) and comparison of the content of aroma compounds in different types of juices, was made. Solid Phase Microextraction in conjunction with gas chromatography (SPME-GC) was used for analysis. Totally 51 different volatile aroma compounds were identified. They were 19 alcohols, 10 aldehydes, 8 esters, 7 ketones, 6 fatty acids and an oxide. As expected, the largest amount of aroma compounds was found in sample of pure elderberry juice.
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Characterization of elder juice on the basis of some chemical parameters
Mizerovská, Lucie ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
The aim of this thesis was to determine selected chemical parameters of elderberry juice namely its wild variety and four cultivated types Albida 08, Albida 09, Dana and Haschberg. The relative density was the lowest for cultivar Albida 09 (1.0149) and the highest for the wild variety of elder from the surroundings of Padochov (1.0337). Values of pH ran within the range of 3.62 for cultivar Haschberg to 4.85 for cultivar Albida 08. The highest titrating acidity was determined by cultivar Haschberg (13.12 g l-1), the lowest content of acids was determined by cultivar Albida 08 (3.47 g l-1). The highest content of reducing sugars had cultivar Albida 08 (9.64%) together with the wild variety of elder from the surroundings of Padochov (9.47 %), the minimum amount of sugars was determined by cultivar Dana (4.79 %). The content of citric acid varied between 4.76 g l-1 by cultivar Dana and 13.48 g l-1 by cultivar Haschberg. The total amino acid content, expressed as a formole number, was the lowest in cultivar Haschberg (12.9) and the highest in the wild variety of elder from the surroundings of Padochov (59.2).
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The assessment of aroma active compounds in elderberry juice
Lukačková, Adéla ; Divišová, Radka (referee) ; Vítová, Eva (advisor)
This work deals with the assessment of aroma active compounds in elderberry juice. In the theoretical part, the characteristic of elderberry, including species, varieties of elderberries, content compounds and use is described. The production of fruit juices and SPME-GC method, which has been chosen for assessment, is shortly summarized here. In the experimental part, identification and quantification of aroma active compounds in 11 samples with various content of elderberry juice combined with other type of fruit juice, diluted or not diluted with water, was made. The fiber CARTM/PDMS 85 µm was used for extraction of aroma compounds. 43 aromatic compounds were identified in total 5 aldehydes, 7 ketones, 18 alcohols, 5 esters and 8 fatty acids. The most of all aroma active compounds were determined in sample containing 10% of elderberry juice with 50% of apple juice and 40% of water, but some of them were not identified. The most of all compounds identified were determined in commercially acquired concentrated elderberry juice sample from Austria.
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The possibilities of the assessment of aroma active compounds in elderberry juice
Kolibačová, Silvie ; Vránová, Dana (referee) ; Vítová, Eva (advisor)
This bachelor thesis is a literature research, which deals with the characteristics of black elderberry, its occurrence, types and how to use it particularly in medicine and food industry. The next section describes the production of fruit juices and methodologies for the determination of aromatic compounds in elderflower juice, which were selected for future measurements. This is the method solid phase microextraction (SPME) and gas chromatography (GC). Almost a hundred different volatile compounds are given in the literature, which are located in different cultures of elderberry and their presence and quantity are dependent not only on the culture, but also on the season, the environment and the method that was used for extraction and determination of aromatic compounds.
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Characterization of elder juice on the basis of some chemical parameters
Šafránková, Petra ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
This study is about characteristic of eldberry juice based on selected chemical properties. In the theoretical part, it is described botanical characteristic, including place of origin and spread. This part is also about the healing effects of elderberry and cultivating and improving of this plant is also mentioned there, together with some varieties of elderberries. In the experimental part, there were made some determinations the same for wild variety of elderberry and for cultivated elderberry. There were not found significant differences in relative density between both samples. According to pH, the more acidic is the cultivated variety of juice and this juice also contains higher content of organic and mineral acids, reducing sugars and citric acid. On the other hand the wild variety juice contains higher total content of amino acids and mineral solids.
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Less conventional botanical sources of cosmetic raw materials
Novotná, Petra ; Vespalcová, Milena (referee) ; Zemanová, Jana (advisor)
The aim of this bachelor’s thesis is an investigation of use of less traditional plant sources in cosmetic industry. This review is focused on black elder (Sambucus nigra), sea buckthorn (Hippophae rhamnoides), quince (Cydonia oblonga), dog rose (Rosa canina), and stinging nettle (Urtica dioica). The substances Isolated from these plants can be used in various cosmetic products. The first section of this search deals with history and botanical characterization of these plants. The next section deals with significant substances contained in these plants and their use not only in cosmetic industry.
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Optimization of conditions and procedures for plant extraction.
SMUTNÍKOVÁ, Kateřina
The thesis deals with the content of selected phenolic compounds in some species of the genus Amaranthus, in black elderberry (Sambucus nigra L.) and buckwheat (Fagopyrum esculentum M.). Phenolic compounds are a group of natural compounds exclusively vegetable character. Flavonoids represent only one group of phenolic compounds. Flavonoids show many positive biological effects, in particular act as antioxidants. Natural flavonoids may cause to prevent from coronary- heard diseases and other diseases associated with older age. In recent years the increased attention is paid to flavonoid investigation due to its biological effects. For the determination of phenolic substances there were used two independent analytical methods. There are the high-performance liquid chromatography (HPLC) and micellar electrokinetic capillary chromatography (MECC). The MECC method was used for determination rutin and free quercetin. The highest content of rutin was found in leaves of buckwheat (76,400 mg/kg of dry weight) and the lowest content of rutin was determined in buckwheat hulls. The highest content of rutin was observed in teas from buckwheat leaves and inflorescence. This amount of rutin corresponds with rutin content in more than two pills of Ascorutin (the most favourite flavonoid medicament in the Czech Republic) The HPLC method was used for quantitative determination of phenolic acids. The content of free quercetin was monitored in all samples. No free quercetin was found both in plant material and in samples of teas. The ethanolic extract from the elderberry inflorescence didn´t contain any free quercetin. Free quercetin wasn?t found in any further samples of teas, which were prepared by described methods.
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