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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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Nutritional comparison of animal-based and plant-based foods
Tichá, Kateřina ; Pejšová, Hana (advisor) ; Chrpová, Diana (referee)
The substitution of animal-based foods with plant-based products is common in some alternative diets, but plant-based substitutes are also increasingly consumed by mainstream customers. The aim of this thesis was to compare animal-based foods with their plant-based alternatives and to assess how nutrition professional and the lay public is informed about the differences between them. A total of 223 respondents, 136 of whom had no education in nutrition, participated in the questionnaire survey. The results showed that the awareness of the lay public about the nutritional composition of plant-based alternatives is significantly lower than that of professionals. Furthermore, professionals pay significantly more attention to information on food labels and consider their diet as healthier than the lay public. In contrast, education in nutrition did not have a significant effect on experience with alternative diets or on the frequency of consumption of plant-based alternatives. The practical part of this thesis included market research as well. Differences in composition and nutritional values were found not only between animal-based foods and their alternatives, but also among plant-based products. Soy drinks appear to be the best plant-based alternative to milk, as their protein content is almost...
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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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Large crabgrass (\kur{Digitaria sanquinalis}) a weed or a crop?
PAUROVÁ, Natálie
The aim of this bachelor thesis was to collect all available information about the occurrence, spread, nutritional value and use of species from the genus Digitaria with the emphasis on the Digitaria sanguinalis in the form of a literature review. Large crabgrass is currently considered a weed plant for its spread in tropical, subtropical and temperate areas. The importance of its regulation in crop stands increases year after year. Its use as a cereal fell into forgetfulness. Other Digitaria species, especially Digitaria iburua and Digitaria exilis, grown in Africa are currently considered a "super food" due to the high level of sulphur amino acids (methionine a cysteine) in the grain.
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Senzorické hodnocení vybraných obilných nápojů
URBAN, Martin
The aim of this diploma thesis was a sensory and nutritional evaluation of vegetable drinks. The analysis focused on rice and oat drink. Part of the population has health problems with milk consumption. Some substitutes can be beverages from legumes, cereals, nuts, etc. Oat and rice drinks does not contain cholesterol, are a source of minerals and vitamins. Rice and oat drink does not contain lactose or milk proteins. The downside is the insufficient amount of protein and the fact that, unlike milk protein, the protein of cereals is poor, deficient. Rice drink does not contain gluten. The sensory analysis aimed to compare individual drinks and determine their differences between samples, to determine the intensity of certain properties and to rank the samples from best to worst. The sensory analysis confirmed the differences between manufacturers. In the case of rice beverages, the evaluators concluded that they perceived the difference between the product of Alpro and Alnatura, with the Alnatura drink being considered the most acceptable. The amount of fat in rice beverages was low (1-1.1 g fat per 100 ml). Drinks also contain little protein (0.1-0.3 g / 100 ml). Oat beverages differed in particular with Alnatura and Delhaize - Bio. The evaluators preferred Delhaize Drink Company - Bio the most. The nutritional composition of the fat-like products is similar to rice beverages (1-1.5 g fat per 100 ml). The amount of protein was slightly higher (0.6-1 g protein per 100 ml). From a nutritional point of view, there is a noticeable difference between cow's milk and oat and rice beverages. The rice and oat drinks that were preferred contained the most sugar and the brewing flavor was the least noticeable.
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Usage of wastewater from RAS for microbial protein production.
SADLOŇ, Patrik
The aim of this diploma thesis was to analyse waste water quality from RAS, verification of its possible cleaning in a model of wastewater treatment plant using heterotrophic bacteria, experimentally compare the influence of used carbon source in the initial phase of bacteria cultivation and evaluation of biofloc usage in fish feed. Analysed water was obtained from rearing tanks, sewage water from mechanical filtration and tap water for filling the system. Wastewater treatment plant (built according to AS VARIOcomp K model) was divided into 3 parts (primary settling, activated part, secondary settling) and then filled with water from running BFT system. For carbon source comparing experiment 4 groups were used: flour, glucose, acetate and glycerol, each in 3 replications. Cultivation took 28 days and at the end the nutritional composition of each BFT system was evaluated. Water analyses showed that sewage water from mechanical filtration is nutrient rich and contain big amount of undissolved solids. This water is not suitable for purification in conventional system without pre-treatment. The model of water treatment plant purified approximately 50 l of water from vortex per day which was pumped back into RAS. Probably it would be capable of purifying bigger volume. Bacteria cultivation using different carbon sources is very similar to start-up of nitrifying bacteria in biofilter at the beginning. It was proved that biofloc is also capable of removing nitrates from water. The biggest measured concentration among groups was 1695 +- 438 mg.l-1 NO3- and in 6 days it decreased to 493 +- 409 mg.l-1. The average FVI for flour, glucose, acetate and glycerol were 102 +- 57; 267 +- 59; 219 +- 26 and 293 +- 9 ml.l-1 at the end of cultivation. Experiment comparing carbon sources also proved that nutritional composition of biofloc is similar to composition of commercial feed. Heterotrophic bacteria are also capable to cumulate heavy metals and mineral matter over time. Experiment with added biofloc to feed in amount 0 %, 25 % and 50 % did not show any statistically significant differences (p < 0,05) on survival rate, FCR and SGR between the groups of juvenile grass carp (Ctenopharyngodon idella).
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