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Analysis of essences in some plant materials
Koloničná, Markéta ; Svoboda, Zdeněk (referee) ; Mikulíková, Renata (advisor)
The peppermint (Mentha piperita) and the levander (Lavandula angustifolia) are the aromatic herbs with the healing and spices effects. Their essencial oils serve to production of the aromatic substances, they are used in the cosmetic and the food industry. In this thesis were analyzed substances which are contained in levander and peppermint oils. These oils were extracted through the destillation with the water steam, next they were analyzed by the gas chromatograph and the mass spectrometer. The aim of the thesis was found which substances contain these oils. In the levander oils were proofed the highest amounts of the cineole, linalool and the linalyl-acetate. In the peppermint oils were proofed the highest amounts of the menthon and the menthol.
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Monitoring of allergenic aroma compounds in foods
Plevová, Petra ; Sůkalová, Kateřina (referee) ; Vítová, Eva (advisor)
This thesis deals with the identification and quantification of aromatic potentially allergenic substances which normally occurs in food, but their amount is not legislatively controlled. These aroma compounds have many positive and negative effects on human body, although they are not main types of allergens, several studies have highlighted their potentially allergenic character. For monitoring of the content of these substances non-chocolate confectionery were chosen as model samples. Theoretical part summarizes the production technology of non-chocolate confectionery from raw materials to final processing. It also deals with the characterization of 26 potentially allergenic aroma substances and their occurrence in nature and also in food or cosmetic products. In the experimental part potentially allergenic aroma compounds occurring in samples of jelly confectionery were identified and quantified using the SPME–GC–FID method.
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Determination of residual substances from the preparation of colloidal systems based on biopolymers
Borůvková, Tereza ; Vávrová, Milada (referee) ; Mravec, Filip (advisor)
Volatile organic compounds could be isolated and concentrated from liquid solution using methods, which are based on analysis of equilibrium gas phase, because of their volatility. The aim of this bachelor´s thesis is determination the amount of residual tert-butanol, belonging to volatile organic compounds, in the samples after lyophilisation. Samples were prepared by mixing hydrofobic sonde and hydrofilic hyaluronan. For mixing these components it is necessary to add organic solvent tert-butanol, which ensures stable environment. Thanks to its presence mixing of probe and hyaluronan occurs. Consecutive lyopfilisation of the sample leads to the disruption of a water cover of hyaluronan and nonpolar hydrogen atoms, which are hidden in it, can interact with hydrofobic probe. Bonding the probe is important in oncology, where this fact could be used in targeted distribution of pharmaceuticals. However presence of tert-butanol is unacceptable in the final product, mainly in medical applications. The object this study is the minimization of residual tert-butanol amount in final lyophilised cake. The method of equilibrium gas phase analysis (static Head-Space) by gas chromatography with flame ionization detection (GC/FID) was used for the determination of its content.
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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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The assessment of aroma compounds in processed cheese analogues
Hornáková, Miroslava ; Babák, Libor (referee) ; Vítová, Eva (advisor)
The aim of this work was to identify and quantify aroma compounds in samples of processed cheese analogues made at Tomas Bata University in Zlin. Analogues are processed cheese products in which lactic part is replaced by another component, either partially or completely. Market price is lower because of this replacement and that is why it is more attractive for the consumer. However, this substitution changes aroma, taste and texture, and also contributes to a reduction of the cholesterol content. Theoretical part is dealing with literature review of processed cheese analogues, focusing mainly on the composition, properties and production technology. In the experimental part 5 samples of cheese analogues made by using different types of fats (butter, apricot, grape, black currant and linseed oil) were analysed, simultaneously used oils were also analyzed. Aroma compounds were isolated by using SPME (solid phase microextraction) method and then determined by GC-FID. The most of aroma active compounds were identified in cheese analogue with patial substitute for grape seed oil instead of butter. The largest concentration of aroma compounds was identified in cheese analogue with patial substitute for linseed oil instead of butter. The black currant oil contained the most of aroma active compounds of all measured samples of oils. This oil also contained the largest concentration of aroma compounds.
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The chosen validation parameters of method for assessment of aroma compounds in processed cheese analogues
Burdějová, Lenka ; Horváthová, Viera (referee) ; Vítová, Eva (advisor)
This Bachelor‘s thesis deals with the issues of method validation for assessment of aroma compounds in processed cheese analogues. The method is based on the isolation of volatiles from the sample using Solid Phase Microextraction (SPME) and their subsequent determination by gas chromatography. The theoretical part focuses on general characteristics, classification and producing technology of processed cheese analogues. Further, aroma active substances contained in cheese analogues, differences from the classic processed cheese and processed cheese analogues occurring on the Czech market are mentioned. The methods for determination of aroma active compounds with a focus on Solid Phase Microextraction and gas chromatography are briefly mentioned. Within experimental part of the work the linearity and repeatability of the SPME-GC method were verified and detection limits and limits of quantification of selected standards were determined. Then the method was applied to chosen samples of processed cheese analogues with addition of different types of vegetable fats.
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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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Aroma profile of cheese analogues
Součková, Šárka ; Pšenáková, Ivana (referee) ; Vítová, Eva (advisor)
This Bachelor’s thesis deals with the issue of processed cheese analogues. It will explain what they are, their chemical composition and properties. The aim is to examine a number of cheese analogue samples with added various types of vegetable fats and identify and quantify the volatile aroma active substances present. Aroma compounds were isolated from samples using the Solid Phase Microextraction (SPME), a fiber with polar stationary phase (CARTM/PDMS) was used and the captured substances were then determined by gas chromatography. The evaluated cheese analogues varied in the type of the contained fat. In total 27 aroma active compounds in different amounts were identified. Cheese analogue with sunflower oil contained the most compounds (24) and the smallest number of aroma substances (16) has been detected in the cheese analogue with coconut fat. The highest concentration of aromatic compounds was found in the analogue with coconut fat and lowest in the cheese analogue with palm fat. Ethanol occurred in all types of analogues in the largest concentration. In conclusion it can be argued that the various analogues varied in the type and the amount of aromatic compounds, depending on the type of fat used.
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