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Analysis of czech garlic varieties
Fähnrichová, Nikola ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This master thesis deals with analysis of Czech garlic varieties in comparison with two varieties from abroad. Alliin and carbohydrates were determined by high performance liquid chromatography with diode-array detector or evaporative light scattering detector. Crude proteins were calculated from total content of nitrogen that was determinated by Kjeldahl method. Elementary analysis was performed by inductively coupled plasma optical emission spectrometry. In theoretical part of this thesis is describes botanical characterization and cultivation of garlic, chemical composition of garlic, especially groups of substances which were analysed in this thesis. Principle of used methods is described too. The experimental part of this work deals with sample and calibration solution preparation and process of analysis. Obtained results from analysed substances are summarized in the tables, discussed and compared with results of analysis of other authors. Between Czech and Spanish/Chinese garlic are slight differences. Garlics contain 24,66 g/kg dry weight of alliin. Content of crude proteins in Czech garlic is comparable to Chinese garlic but the Spanish garlic has just half of amount crude proteins. Elementary analysis also includes significant differences. Czech varieties contain higher amount of phosphorus, iron and zinc. On the contrary, content of potassium in foreign garlic is higher than in Czech Republic and the analysed amount is 15 g/kg dry weight.
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Characterization of minor fruit varieties in terms of use in the food industry
Jurečková, Zuzana ; Vítová, Eva (referee) ; Golian, Jozef (referee) ; Diviš, Pavel (advisor)
The thesis deals with one group of small fruits, the genus Ribes, ie currants, and gooseberries. It assesses their physical and chemical parameters with respect to the possibility of use in these properties for the design of a new type of product – beverages. Titration, spectrometric and other methods were used for the evaluation of these properties. A total of fifteen of these methods were available (total juice yield, juice pH, total dry matter, soluble fruit dry matter, titratable acidity, formolic number, reducing carbohydrate content, D-glucose, D-fructose and sucrose content, total polyphenolic substance content, anthocyanins, vitamin C and total antioxidant capacity) and a total of nine analytes (copper, iron, magnesium, phosphorus, zinc, manganese, potassium, calcium and sodium) were selected for the determination of mineral elements. For two years (harvest 2014 and 2015), these parameters were monitored for color variants of currants (white, red and black) and gooseberries (green-fruited, yellow-fruited and red-fruited). A total of six white varieties were tested in the group of currants - Olin, Jantar, Primus, Blanka, Viktoria and Orion, eleven varieties of red currants - Junnifer, Jesan, Detvan, Rovada, Rubigo, J.V.Tets, Tatran, Losan, Kozolupský raný, Stanca, NŠLS 11/6 and eleven varieties of black currant varieties - Ometa, Démon, Triton, Ben Hope, Ruben, Ben Gairm, Ben Lomond, Moravia, Ben Conan, Fokus and Ceres. A total of five varieties of green-fruited gooseberries were tested - Zebín, Mucurines, Rixanta, Rodnik and Prima. Yellow-fruited gooseberries were available in four varieties - Lemon Giant, Invicta, Golden Fig and Darek. The red-fruited gooseberries included varieties - Rolonda, Alan, Karat, Karmen, Krasnoslawjanskij, Himnomacki Rot, Remarka, Tamara and Black Neguš. Using Tukey's test, an analysis was performed and by scoring individual varieties based on the results of individual analyzes, a list of recommended varieties was compiled for further work on the development of a new beverage. Unfortunately, in 2015 there were very few fruits of green-fruited and yellow-fruited gooseberries, so it was decided that the volume of fruit will fall on the testing of bioactive substances. Therefore, at the end of the work, it is not possible to objectively evaluate these varieties of gooseberries in the whole range of analyzes. Therefore, the point evaluation of varieties was based on the averages of individual varieties. The red-fruited varieties were available in full, and therefore a full evaluation could take place. The most significant differences between red gooseberry varieties were in the content of bioactive substances (the content of polyphenolic substances, anthocyanin dyes, and vitamin C) and antioxidant capacity. These results were provided to the food subject, which continued to work with these values. Based on this project, utility model No. PUV 2016-33171 and the resulting combined drink based on wine and fruit juice were developed.
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Study of selected technological properties of licorice mass
Gajdušek, Martin ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the study of selected technological properties of liquorice matter. By microscopic observation it was found that at a content of more than 10% of the boiled starch grains or more than 30% of the non-swollen grains, the mass does not achieve the desired properties for further processing. Technological loss during drying depends mainly on time, but also on location in the oven, both in height and space. The highest technological loss was achieved mainly in the highest positions in the oven. By liquid chromatography was determined 11.8% glucose, 9.2% fructose, 23.3% sucrose in liquorice mass prior to cooking; 11.9% glucose, 9.4% fructose, 22.6% sucrose in cooked matter; 12.7% glucose, 10.8% fructose and 20.1% sucrose in dried liquorice products.
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Chemical and sensory characterization of cider made from apple cultivars ordinarily grown in Czech republic
Strapcová, Zuzana ; Vítová, Eva (referee) ; Pořízka, Jaromír (advisor)
This master thesis deals with the investigation of selected chemical and sensory characteristics of ciders, which were made from four selected apple varieties. The theoretical part describes the chemical composition of apples, cider, the technology of production and production in the world. The next section describes the analytical methods used to determine chemical characteristics not only in ciders but also in other alcoholic beverages. The experimental part focuses on the determination of chemical characteristics such as the content of organic acids, carbohydrates, total phenolic content, alcohol antioxidant activity and elemental composition. The purpose of the work was to find out how different varieties differ in chemical composition. The produced ciders were subjected to sensory analysis to evaluate the selected cider sensory parameters, which were in the natural state and with the addition of carbon dioxide. The results show that ciders of different varieties differ in chemical composition. Malic acid was the most cider's abundant of the organic acids in the range of 2759 – 4411 mg·l-1. Another acid represented was lactic acid in the range of 166,2 – 288,1 mg·l-1. The glucose content of each cider was determined between 845,3 – 1159,8 mg·l-1and fructose 32,6 – 406,7 mg·l-1. Potassium 944,29 – 1073,98 mg·l-1 was the most represented of all elements. The total phenolic content was determined to be in the range of 164,2 – 214,1 mg of GAE·l-1and the antioxidant activity of 0,192 – 0,318 mg·l-1. These differences in chemical composition were also reflected in sensory evaluation. According to the overall assessment, the best cider was made from the Granny Smith variety, which contained the most organic acids and carbohydrates. It has been found that by adding carbon dioxide, sensory parameters such as colour, taste and smell are altered.
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Evaluation of the influence of the pasterization and filtration on selected chemical components of beer
Vopelková, Dominika ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
The aim of this work was to study the influence of the pasteurization and filtration on selected chemical compounds in beer. Specifically, the influence on elemental composition, content of organic acids, carbohydrates and phenolic substances was studied. Optical emission spectrometry with inductively coupled plasma (ICP-OES) was used for elemental analysis of beer. Analysis of organic acids was evaluated by Ion chromatography. For analysis of carbohydrates was used High performance liquid chromatography with ELSD detector (HPLC-ELSD), phenolic compounds was evaluated by HPLC with diode array detector (HPLC-DAD). Data from analysis of beer was performed by usage of statistical methods (analysis of variance and principal component analysis). Parameters that showed the most significant differences between individual groups of beers were obtained. Correlations between the variables and the technological beer processing operations were found. 12 parameters of total 23 were affected. The effect of filtration and pasteurization was observed in content of the iron, silicon, potassium and magnesium, malate, monosaccharides glucose and fructose and phenolic compounds.
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Monitoring the stability of the beer brewing process
Tichá, Anna ; Štursa, Václav (referee) ; Diviš, Pavel (advisor)
The bachelor thesis deals with the analysis of 3 samples of the same beer, brewed in different batches of the brewing process. The analyzed sample is Dalešická jedenáctka - light lager of 11% of the Stock Brewery Dalešice, a.s., which was taken directly from the lager tanks in the brewery. The aspect we have examined were total protein content, total carbohydrate content, maltose content, total polyphenol content and ethanol content. The Hartree-lowry method was used to analyzed the total protein content. Total carbohydrates were measured spectrophotometrically using anthrone reagent. The maltose content was analysed by HPLC with an ELSD detector. The total polyphenol content was analyzed by the Folin-Ciocaltau reagent method and measured spectrophotometrically. The ethanol content was analyzed on a HPLC using a refractometric detector. The aim of the work was to compare to what extent the process of beer production is stable and what parameters may change in the final product
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Determination of honey authenticity and adulteration by anion exchange chromatography
Ždiniaková, Tereza ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Cieľom tejto diplomovej práce je stanoviť kvalitu a zloženie medu, taktiež stanoviť jeho botanický pôvod na základe profilu sacharidov v mede. Med je prírodný produkt vysokej kvality a vďaka značnej spotrebe a nemalej trhovej hodnote je tiež terčom na falšovanie. S cieľom identifikovať podvody a cudzorodé látky, pochádzajúce z cukrových sirupov, boli analyzované oligosacharidy a polysacharidy na báze maltodextrínov. Teoretická časť popisuje chemické zloženie medu a hlavné princípy aplikovanej inštrumentálnej techniky. Poskytuje literárny prehľad existujúcich analytických metód na stanovenie sacharidov prítomných v mede a na odhalenie jeho falšovania. Boli definované hlavné body falšovania a autenticity, vrátane legislatívnych aspektov a opisu bežných druhov falšovania. Experimentálna časť obsahuje postupy, ktoré vedú k vývoju a optimalizácii chromatografických podmienok a parametrov elektrochemického detektora na stanovenie sacharidov a maltodextrínov (oligosacharidov a polysacharidov) vo vzorkách medu. Použitá analytická technika bola vysoko účinná aniónovo-výmenná chromatografia (HPAEC) spojená s pulzným amperometrickým detektorom (PAD). Vyvinutá a optimalizovaná chromatografická metóda bola taktiež validovaná z hľadiska linearity, dynamického rozsahu, analytických limitov, presnosti a správnosti. Na záver bola táto vypracovaná metóda úspešne zhodnotená analýzou autentických a falšovaných vzoriek medu rôzneho botanického pôvodu pochádzajúcich z členských štátov EÚ.
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Mineral nutrients dynamics of hemiparasite Viscum album L. and its host Tilia cordata Mill
Nikitina, Tatiana
The presence of hemiparasitic plants can potentially harm urban trees, which are valuable resources due to their aesthetic and environmental functions. Therefore, this study examines the nutrient dynamics of European mistletoe (Viscum album L. subsp. album) and its host tree small-leaved linden (Tilia cordata Mill.) during the vegetation season. The concentration of all macronutrients was higher in mistletoe compared to the host tree, except for calcium. Deficiencies in phosphorus and potassium were observed in Tilia leaves during the vegetation season. The concentration of soluble non-structural carbohydrates in Tilia leaves was significantly higher than that of Viscum. Leaf spectral reflectance showed differing outcomes for the two species, with Tilia displaying a quicker senescence rate than Viscum's current-year leaves and slower and prolonged development of current-year Viscum leaves. The study emphasizes the accumulation of macronutrients by mistletoe at the expense of hot tree resources.
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Stanovení biologicky aktivních látek v čerstvých ovocných šťávách
Františová, Gabriela
Fruit is a valuable source of biologically active compounds. These compounds are often contained in minor amounts. A large proportion in fruit is made up of carbohydrates. In this work, the contents of vitamin C, polyphenols, flavonoids, glucose, fructose and sucrose in fresh fruit juices were determined. Aronia, strawberries, josta, raspberries, blackberries, white and blue grapes, white and red currants were obtained from a private garden, blueberries were collected in the wild. The vitamin C and carbohydrate concentrations were determined using HPLC. The total polyphenol and flavonoid contents were measured using spectrophotometry. Of the biologically active compounds, polyphenols were the most abundant in the fruit juices. The highest contents of polyphenols and flavonoids were detected in aronia (7905.81 ± 622.65 mg/l and 4714.82 ± 667.37 mg/l). Josta was the most significant source of vitamin C (721.90 ± 1.79 mg/l). Fructose in white grapes was the highest concentrated compound (93.81 ± 3.74 g/l). The highest glucose content was detected in aronia (83.95 ± 4.80 g/l) and white grapes (90.94 ± 3.48 g/l). Sucrose was detected in strawberries, gooseberries and raspberries.
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Posouzení trvanlivosti vybraných druhů dřev pro obchodovatelný výrobek
Sion, Matěj
In this thesis, the problem of the resistance of terrace boards to biological degradation. The following woods were chosen for the experiment: 1) Garapa (Apuleia leiocarpa Vog.) → is a representative of tropical woods and at the same time a species required by customers. 2) Mulberry (Morus) → a possible alternative in future years. 3) Acetylated European alder wood (Alnus glutinosa) → a possible alternative, when this method of modification appears to be very effective. The selected woods were tested according to the ČSN EN 350 standard for resistance to the wood decay fungi of white rot (Trametes versicolor) and brown rot (Gloeophyllum trabeu) and Coniophora puteana). The second part of this thesis was the determination of the total content of extractive substances (ES), phenolic substances (FS), carbohydrates (C), and pH values of aqueous leachate selected wood species. All samples were tested and compared with each other. The wood of the mulberry tree was evaluated and as to how these properties change along the radius of the trunk. The selected woods have been found to be suitable for decking. Weight losses (white and brown rot) were in negative values, so the fungi were not able to attack the wood and it was classified in durability class 1 "very durable". From the point of view of chemical composition, it was found that the most chemical substances are contained in the wood of the mulberry tree, garapa, and the least acetylated alder. In the case of the mulberry tree, it was also found that the amount of chemical substances varies depending on the position along the stem radius. The high resistance of garapa and mulberry to wood-rotting fungi is mainly caused by the content of chemical substances. The resistance of acetylated alder was due to the acetylation process.
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