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Analysis of onion and garlic samples of different geographical origin
Korček, Jakub ; Mikulíková, Renata (referee) ; Diviš, Pavel (advisor)
Presented master thesis dealt with the analysis of garlic and onion samples and tried to find correlations between chemical composition and country of origin. The parameters examined were dry content, crude protein content, concentration of phenolic compunds, carbohydrate content (fructose, glucose), alliin content and concentration of selected elements (P, Mg, Ca, Na, K, Fe, Zn). Average content of dry matter of fresh samples was 35,84 ±2,12 g/100 g and of dehydrated samples was 90,61 ±2,90 g/100 g. Concentration of phenolic compounds was measured spectrophotometrically with Folin-Ciocault reagent. Average phenolic compounds content of samples was 0,1840 ±0,1286 GAE g/100 g. Crude protein content was measured by Kjeldahl method, and calculated from total nitrogen content. Carbohydrates were measured by HPLC-ELSD after hydrolysis of fructans. Average content of fructose of garlic samples was 57,014 ±0,863 g/100 g, of onion samples was 33,718 ±1,168 g/100 g. Average content of glucose of onion samples was 22,633 ±0,405 g/100 g. Alliin content was measured by HPLC-DAD method. Average alliin content of fresh samples was 4,644 ±0,446 g/100 g and of dehydrated samples was 1,962 ±0,180 g/100 g. Elemental analysis was conducted by ICP-OES method. Average concentration of selected elements was: P 2,15 ±0,11 mg/g, Mg 0,638 ±0,03 mg/g, Ca 1,246 ±0,05 mg/g, Na 0,550 ±0,08 mg/g, K 7,49 ±0,41 mg/g, Fe 79,3 ±6,16 mg/kg, Zn 11,4 ±3,33 mg/kg. Obtained data were statistically processed on significance level 0,05. Based on the principal components analysis, it was found, that the best parameters to differentiate samples from Czechia, Poland and Ukraine from other countries were content of nitrogen, phosphorus, magnesium, sodium and calcium. It was also discovered, that genus differences between onion and garlic have greater significance than geographical differences.
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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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Analysis of onion and garlic samples of different geographical origin
Korček, Jakub ; Mikulíková, Renata (referee) ; Diviš, Pavel (advisor)
Presented master thesis dealt with the analysis of garlic and onion samples and tried to find correlations between chemical composition and country of origin. The parameters examined were dry content, crude protein content, concentration of phenolic compunds, carbohydrate content (fructose, glucose), alliin content and concentration of selected elements (P, Mg, Ca, Na, K, Fe, Zn). Average content of dry matter of fresh samples was 35,84 ±2,12 g/100 g and of dehydrated samples was 90,61 ±2,90 g/100 g. Concentration of phenolic compounds was measured spectrophotometrically with Folin-Ciocault reagent. Average phenolic compounds content of samples was 0,1840 ±0,1286 GAE g/100 g. Crude protein content was measured by Kjeldahl method, and calculated from total nitrogen content. Carbohydrates were measured by HPLC-ELSD after hydrolysis of fructans. Average content of fructose of garlic samples was 57,014 ±0,863 g/100 g, of onion samples was 33,718 ±1,168 g/100 g. Average content of glucose of onion samples was 22,633 ±0,405 g/100 g. Alliin content was measured by HPLC-DAD method. Average alliin content of fresh samples was 4,644 ±0,446 g/100 g and of dehydrated samples was 1,962 ±0,180 g/100 g. Elemental analysis was conducted by ICP-OES method. Average concentration of selected elements was: P 2,15 ±0,11 mg/g, Mg 0,638 ±0,03 mg/g, Ca 1,246 ±0,05 mg/g, Na 0,550 ±0,08 mg/g, K 7,49 ±0,41 mg/g, Fe 79,3 ±6,16 mg/kg, Zn 11,4 ±3,33 mg/kg. Obtained data were statistically processed on significance level 0,05. Based on the principal components analysis, it was found, that the best parameters to differentiate samples from Czechia, Poland and Ukraine from other countries were content of nitrogen, phosphorus, magnesium, sodium and calcium. It was also discovered, that genus differences between onion and garlic have greater significance than geographical differences.
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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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The genetic basis of Czech garlic "paličák" (A. sativum L. ssp. ophioscorodon) focusing on the biosynthetic pathways of the secondary metabolites
Čermák, Vladimír ; Ovesná, Jaroslava (advisor) ; Demnerová, Kateřina (referee)
Czech bolting garlic (Allium sativum L.) is the name for Czech varieties, which are categorized into subspecies sativum ssp. An inflorescence production and specific onion morphology is typical for this type of garlic. The genetic basis, that has been described by the analysis of microsatellites, are discussed in this thesis. Transcription analysis has revealed a large number of unigenes that have been assigned by genetic ontology to individual functions in the organism. Therefore, genetic differences from other varieties were confirmed. The impact of the environment and cultivation practices, including large- scale production, is being explored. The results can be used for further research or breeding. Consumers and experts have rated the Czech bolting garlic as a variety with a distinctly pungent taste and aroma. Substances causing this strong characteristic taste are secondary metabolites, alk(en)ylcysteine-S-oxides (ACSO), especially alliin and methiin. Chemical analysis did not confirm the exceptionally high value of these taste precursors or other substances that should distinguish Czech bolting garlic. Secondary metabolism includes other important substances that are used mainly in pharmacy and healthcare, where garlic has been used for thousands of years due to antibacterial effects,...
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