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The influence of microflora on the sensoric characteristic of the wine
Petrášová, Ludmila ; Vítová, Eva (referee) ; Vránová, Dana (advisor)
The bachelor thesis is focused on the influence of the microflora on the sensory characteristics of the wine. The theoretical part provides information of the botanical description of Grüner Veltliner grape wine varietal, as well as its chemical composition, the white wine processing technology, and the influence of yeast on the aroma profile of this varietal. The experimental part describes the method of determining the aroma-active compounds by gas chromatography in combination with solid phase micro-extraction (SPME-GC). The object of the study was to measure samples of four different cider varieties of Grüner Veltliner during the fermentation process, and to compare the aromatic compounds in the cider with the indigenous yeast and in the cider where spontaneous fermentation was used.
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Assessment of aroma active compounds in unconventional fruit types
Krchňavá, Petra ; Divišová, Radka (referee) ; Vítová, Eva (advisor)
This bachelor’s thesis deals with the determination of aroma compounds in selected drinks produced from chokeberry (Aronia melanocarpa). The theoretical part is focused on the description of this plant, its chemical composition, properties, influence on the human body and possibility of utilization and processing. In the experimental part the aroma compounds in samples of sirup and liqueur from chokeberry were identified and quantified. . The aroma compounds were extracted by solid-phase microextraction and analysed by gas chromatography. A total of 43 compounds were identified. Concurrently, the sensory evaluation of samples was carried out. The profile test and evaluation using scales were used for evaluation of overall pleasantness and intensity of taste and odour. The contribution of selected descriptors (fruit, sweet, acid and other taste and odour) to overall sensory quality of samples was also judged.
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The assessment of aroma active compounds in cheeses
Ryglová, Hana ; Diviš, Pavel (referee) ; Vítová, Eva (advisor)
This work deals with aroma active compounds of Edam cheese, i.e. natural hard cheese with low heat curd. Aroma active compounds contribute to overal aroma of cheese. They are volatile compounds, which include alcohols, aldehydes, ketones, fatty acids, esters, lactones, terpenes etc. These compounds were identified and quantified using SPME/GC/FID method in the model samples of Edam cheese, produced at Tomas Bata University in Zlin. In total 18 volatile compounds were identified, 3 aldehydes, 4 ketones, 7 alcohols, 1 ester and 3 acids. Differences in number of compounds identified, as well as in the contents of them, were found between samples. Low number of compounds and also their low total content correspond to the initial phase of cheese ripening.
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Assessment of aroma active compounds in chosen fruit types
Rodzíková, Martina ; Vespalcová, Milena (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the assessment of aroma active compounds in less known berries, gooseberries. In the theoretical part the general characteristics, biological signs and properties of selected varieties, chemical composition and structure of the components, drug effects, the possibility of processing and use of gooseberries are mainly described. The main aim of this thesis was to determine aroma active substances in selected varieties of gooseberry fruits using SPME-GC method. Aroma active compounds were first extracted by solid-phase microextraction and then assessed by gas chromatography.
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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 unconventional fruit types
Melikantová, Marcela ; Pšenáková, Ivana (referee) ; Vítová, Eva (advisor)
The aim of this bachelor thesis is the assessment of aroma active compounds in unconventional fruit types, sea buckthorn (Hippopha rhamnoides L.) was chosen as a model sample. The first part is focused on the description of these plants, their chemical composition and use. The experimental part is focused on identification and quantification of aroma compounds in chosen cultivars of sea buckthorn using SPME-GC-FID method. In total, eleven cultivars were analysed. The cultivar Krasna was found as having the most aromatical profile (the highest content of aroma compounds identified). Ethanol, 3-hydroxy-2-butanone, ethanal, butyl acetate and acetic acid were the most often occuring compounds.
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Assessment of aromatic compounds with allergenic effect
Obrdlíková, Blanka ; Sůkalová, Kateřina (referee) ; Vítová, Eva (advisor)
The thesis deals with the determination of allergenic fragrances in cosmetics. The theoretical part is focused on the description of cosmetic products, the use of fragrances in the preparation of cosmetics, obtaining fragrances and their allergenic effects on the human body. In the practical part the SPME-GC-FID method is used for the determination of aromatic substances with allergenic potential in selected cosmetic products (natural creams and toilet water).
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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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The content of allergenic aromatic compounds in chosen food types
Fidrichová, Ivana ; Dvořák, Miloš (referee) ; Vítová, Eva (advisor)
This thesis describes properties, origin, usage and methods of obtaining fragrances of vegetable origin, which are common part of food products. Although the aroma substances are not classified as the main group of allergens, in many cases there is a warning of their allergic potential. 26 crucial fragrance allergens and related restrictions are set by the European Cosmetic Regulations. There is no coincident regulation for food processing industry so far. The practical part dealt with identification of potential allergenic fragrances in randomly selected food products.
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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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