The diplom thesis deals with comparation od the wines aged in different types of barrique barrels. In the theoretical part there are described types and origin of the wood, processing of the wood and chemical compounds, which are brought into the wine during aeging. Practical part deals with comparation of the data from spectrophotometry and chromatography analysis.

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This diploma thesis will be focused on the identification and quantification of PAHs with molecular mass exceeding 278 Da by separation and spectrometric methods available at the laboratories of ICTEP.

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Tereza Šmidrkalová Supervisor: Doc. RNDr. Dalibor Šatínský, Ph.D. Title of Diploma Thesis: Using of HPLC for illegal colorants determination in foods. This thesis deal with looking for optimal conditions for determination of Sudan dyes. High performance liquid chromatography (HPLC) was used for determination. During searching several various columns and mobile phases were tested. For validation of separation conditions Ascentis Express F5 column (100 x 4,6 mm, 2,7 μm) was used. Detection was measured at a wavelength of 500 nm and 426 nm. Separation used gradient elution with mobile phase of acetonitrile - water at a flow rate 1 ml/min. Injection volume was set to 5 μl. During measuring validation parametres was used on-line SPE extraction in HPLC system on precolumn Ascentis Express C18 (5 x 4,6 mm, 2,7 μm) with washing mobile phase 5% solution of acetonitril - water before separation. Optimalization and validation used only standards and method was suggested for other testing and using real samples. Keywords: high performance liquid chromatography (HPLC), Sudan dyes

Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Proefschrift Universiteit van Amsterdam. / Auteursnaam op omslag: Edwin P.C. Mes. Met bibliogr., lit. opg. - Met samenvatting in het Engels.

Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

PhD dissertation thesis "Study of correlation of quality parameters of wines and wine distillates" was done at Department of Post-Harvest Technology of Horticultural Products, Faculty of Horticulture, Mendel University of Agriculture and Forestry in Brno during 2006 - 2012. Samples of wines and samples of distillates made from these wines were analysed using liquid-liquid extraction method (LLE) followed by gas chromatography analysis (GC). Potential characteristics -- chemical markers were determined: trans-linalool oxide and cislinalool oxide which are typical for Muscat Ottonel and tetradecanote, ethyl 3- methylpentanoate for Pinot Blanc. In wine distillates, ethyl 2-methylbutanoate, ethyl 3- methylpentanoate, 1,1-diethoxybutane, diethoxypentane were determined, however none of these substances were found in wines. These substances probably originate as a result of esterification process during ageing of wine distillates after distillation process. Differences in chemical composition of wine distillates made from red wine grape cultivars were analysed using main component method. Group of substances such as ethyl butanoate, hexanoate, octanoate, decanoate, dodecanoate and diethyl succinate can be considered as possible markers identifying wine distillates from red wine grape cultivars and white grape cultivars. Characteristic aroma of grape variety was recognisable in wine distillates from Muscat Ottonell and Blue Frankish varieties. Samples of wine and wine distillates were analysed using Solid-phase micro extraction (SPME-headspace) technique followed by Gas chromatography--mass spectrometry (GCMS). Negative correlation between 1-hexanol content and intensity of aroma was discovered in wine distillates. Characteristic aroma of grape variety showed significantly in distillates from Pinot Gris (RS_2) and in distillates from red wine grape cultivars, particularly Saint Laurent (SV) and Pinot Noir. Based on analysis of samples of wine distillates from red wine grape cultivars, ten major terpentic aromatic substances were determined (o-cymen, limonen, cis-b-ocimen, cislinalool oxid, linalool, isoborneol, terpinen-4-ol, a-terpineol, trans-sabinyl acetate a transkalamenen). All these substances influence aroma of grape variety. Both centred log ratio transform (clr) and main component method were applied and similarity in aroma of wine distillates was found and it was discovered that aroma of wine distillate from varieties Merlot, Pinot Noir and similar ones are influenced by terpenoids cis-linalool oxid, linalool, 94 isoborneol, terpinen-4-ol a a-terpineol. On the other hand, aroma of wine distillates from varieties Blue Portugieser and Cabernet Sauvignon are influenced by o-cymen, limonen, trans-sabinyl acetate and trans-kalamenen. Analysis of terpentic content wine distillates was carried out using Solid-phase micro extraction (SPME-headspace) technique followed by Gas chromatography--mass spectrometry (GC-MS).Major terpentic substances identified are limonen, linalool, a-ylangen, b- bourbonen, g-kadinen, trans-nerolidol, 2,3-dihydrofarnesol and (2-cis, 6-trans)-farnesol. Verifiable differences were discovered between various distillates types. Predominantly mono-terpentic substances were identified in wine distillates; in grappa there were also identified sesquiterpenic substances which are characteristic for these types of distillates.

Gas chromatography with mass spektrometry and gas chromatography with flame ionization detector were used for the determination of volatile compounds in raw material for beer production, in intermediate products and in beer. Isolation of compounds with low boiling point was optimized using purge and trap analysis, solid phase microextraction, liquid extraction, and static headspace. Solid phase microextraction was proved to be the most useful for determination of Maillard reaction products that are formed during kilning and roasting of malt, hop essential oils and volatile substances produced by fermentation. The ratio of hop essentials oils with lower boiling point (alfa-humulene, beta-farnesene and beta-caryophyllene) decrease during wort boiling. Maillard reaction products are formed during wort boiling, although the content of 3-methylbutanal and maltol is reduced by evaporation. Higher concentration of volatile substances contained top-fermented beer except 3-methyl-1-butanol. The Dudák Premium proved the best results of the analyzed bottled beers. The Stella Artois contained the lowest concentration of volatile compounds.

Aromatic compounds belong to the most valuable substances that give the wine a distinctive expression and are important for sensory evaluation of wine. We chose two samples of white wine - Grüner Veltliner and Sauvignon, where we have set aromatic compounds. Wines were concluded with two different closures (screw cap and classic cork) and then these wines were stored for one year in two conditions different especially by temperature - cool in the cellar and at room temperature. After a year of storage, we have set the aromatic compounds again. The most significant decrease was in the esters of higher alcohols with acetic acid (especially isoamyl acetate and hexyl acetate). These esters are typical for young wines and give them fruitiness particularly. The decrease of these substances was detected in both conditions of storage, but during storage at room temperature was more pronounced. Impact of the closure wasn`t proved. Temperature is a very important factor which influences the aromatic compounds during storage.