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Assessment of chosen aroma compounds in foods
Greifenthalová, Ivana ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This diploma thesis is focused on the problematic of assessment of 26 most important allergenic aroma compounds in foods, flavoured herbal teas were chosen as the model samples. Aroma is the one of the main characteristics of tea, which is closely linked to taste and odour. The theoretical part of this work is focused on the characteristics of tea, tea types, producing technology, classification according to the fermentation and also their undeniable impact on the human organism. In the experimental part, the allergenic aroma compounds in 10 chosen samples of flavoured tea were identified and quantified using the solid phase microextraction (SPME-GC-FID) in conjunction with gas chromatography. The work also includes sensory evaluation of taste and smell of tea samples by qualified assessors.
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The content of aroma active compounds in sweets
Maňáková, Adriena ; Vespalcová, Milena (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the assessment of aroma active compounds in non-chocolate confectionery. In the theoretical part the production technology of non-chocolate confectionery from raw materials to final product is described. Furthermore, aroma active substances, including potentially allergenic, are characterized, and the method for their determination by solid phase microextraction and gas chromatography with mass spectrometry is briefly described. The aim of the experimental part was identification of volatile substances and subsequent quantification of 24 potentially allergenic aroma substances by the HS-SPME-GC/MS method. Gummy candies, purchased in the regular market, were used as model samples. The differences in the number and type of volatile compounds were found between the samples. Overall 230 volatile compounds were indetified including 8 allergens. These were composed of 55 alcohols, 68 esters, 29 alkenes, 18 aldehydes, 25 ketones, 2 ethers, 3 epoxides, 9 carboxylic acids and 21 other compounds.
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Assessment of chosen aromatic compounds in foods
Ascherová, Adriana ; Buňka, František (referee) ; Vítová, Eva (advisor)
This diploma thesis is focused on aromatic substances occurring in food. The theoretical part describes their characteristics, the use of fragrances of plant origin for flavoring of food and points to their possible negative effects on the human organism. Twenty six potentially allergenic fragrances are thus identified in European legislation and an overview of their physical properties, occurrence and use is also processed in this work.The aim of the experimental part was to develop and validate a method for assessment of fragrances using headspace solid phase microextraction combined with gas chromatography (HS-SPME-GC-FID). The following parameters have been validated : repeatability, linearity, limits of detection (LOD) and limits of quantification (LOQ). The HS-SPME-GC-FID method was finally applied to selected samples of foods commonly available on the market.
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Assessment of chosen aromatic compounds in foods
Škopová, Jitka ; Buňka, František (referee) ; Vítová, Eva (advisor)
The thesis deals with the issue of potentially allergenic aroma compounds in food. Aroma compounds suitable for food flavouring are mainly of plant origin. These aroma compounds and their mixtures have a lot of positive and negative effects on human organism. Although the aroma compounds are not among main groups of allergens, several studies indicate a potential risk of allergenic effects of some aroma compounds. The theoretic part of this thesis focuses on aroma compounds of plant origin and gives an overview of 26 the most important fragrance allergens according to the European cosmetic legislation. The aim of the experimental part was to verify the selectivity and appropriateness of the currently used methodology of headspace solid-phase microextraction and gas chromatography-flame ionization detection (HS-SPME-GC-FID) for determination of selected allergenic aromatic active compounds. Secondly, it is to use a proven method for a wide spectrum of real food products.
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Assessment of chosen aromatic compounds in cosmetics
Novotná, Petra ; Souralová Popelková, Miriam (referee) ; Vítová, Eva (advisor)
This master thesis deals with the assessment of selected fragrant substances in cosmetic products. At the beginning the occurrence, methods of acquiring and application of these substances is described. They are essential components primarily in cosmetic products, however they can cause an allergic reaction in sensitive individuals. The theoretical part of this thesis also describes the cause and the progress of these undesirable effects. There are several hundreds, up to thousands fragrant substances used in the perfume industry, from which 26 was designated by the European regulations as potential allergenic fragrant substances and their content is regulated. Legislative standards as well as the overview of the methods used to determine these fragrances are given here. The experimental part is focused on the development and validation of the separation methods for determining of the selected and potentially allergenic fragrant substances. The method used was a solid phase microextraction using Carboxen/Polydimethylsiloxane fiber combined with a gas chromatography coupled to a flame ionization detector (SPME-GC-FID). Amylcinnamyl alcohol, benzyl alcohol, cinnamyl alcohol, coumarin, lyral, ?-isomethyl ionone were among the determined allergenic substance. Consequently, this method was also applied on 10 selected cosmetic products specimens, in which the linalool and geraniol were identified as the most common allergenic substances.
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Assessment of aromatic compounds of plant origin in foods
Jelínková, Monika ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The aroma compounds suitable for food flavouring are mainly of plant origin. It is necessary to take into account the possible allergic effects of some of them. The theoretic part of this thesis is focused on aroma compounds and their biological effects. It also describes methods useful for their isolation and analysis with a nearer intent on the methods used in this thesis - solid phase microextraction and gas chromatography. The aim of the experimental part was to establish, optimise and validate the method for determination of allergic aroma compounds chosen and subsequently to enable its using in wide spectrum of food and other products.
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The presence of allergenic aroma compounds in sweets
Plevová, Petra ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This thesis deals with the determination of aroma active compounds in non-chocolate confectionery and their influence on the sensory properties of these sweets. The theoretical part is focused on the 26 potentially allergenic substances and their determination by SPME-GC-FID (a solid phase microextraction, gas chromatography with flame ionisation detector) and sensory analysis. In the experimental part SPME-GC-FID method was used to identify and quantify aroma active substances contained in the selected samples of confectioneries commonly available in food market and find out influence of presence and amounts of these substances on sensory profile of selected confectionery.
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Assessment of chosen aroma compounds in foods and cosmetics
Obrdlíková, Blanka ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
This diploma thesis is focused on the problematic of assessment of allergenic aroma compounds in various matrices. In the frame of European legislation 26 of potentially allergenic compounds are stated, whose content in cosmetic products is limited. In the case of foods there is not such restriction so far. In the experimental part, the allergenic aroma compounds in chosen samples of cosmetic and food samples were identified and quantified using Solid phase microextraction in conjunction with gas chromatography. Sensory evaluation of aroma or taste is also included.
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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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