National Repository of Grey Literature 34 records found  beginprevious25 - 34  jump to record: Search took 0.01 seconds. 
Waste materials utilization for preparing hydrolysates for the fermentation phase.
Vadovičová, Natália ; Hrstka, Miroslav (referee) ; Babák, Libor (advisor)
Bachelor thesis focuses on the study and comparison of different types of hydrolysis, their optimization and maximization of yields for the upcoming fermentation. Orange peel was chosen as a substrate to conduct the experiments. First, the substrate was mechanically grinded to form a suspension. Each suspension then underwent one out of the examined methods of hydrolysis. Chosen methods were physical, such as microwaves, increased temperature or ultrasound, and chemical acidic and alkaline. Combinations of both types were also examined. The last optimized method was enzymatic hydrolysis. First set of experiments was conducted using enzymes Novozymes® NS50013 and NS50010. Production of cellulase and pectinase enzymes by A. niger during solid-state fermentation that lasted 10 days was also studied. The yields of reducing sugars of all the experiments were calculated using the Somogyi-Nelson method. Enzymatic hydrolysis was proven to be the most effective using the combination of both of the enzymes for a period of 96 hours at pH = 4.5 and temperature 45 °C. Yield of the reducing sugars under these conditions reached 27,4241 ± 0,0007 gl-1.
The measurement of total alkaloids in tobacco
Pipková, Renata ; Vránová, Dana (referee) ; Omelková, Jiřina (advisor)
The aim of this diploma thesis is the assay of total alkaloids in different tobacco types. To measure the content of total alkaloids are utilized types of tobacco used for preparation of tobacco blends and consecutive production of cigarettes. The samples of analyzed tobacco include various countries of cultivation and different crop years. There is described tobacco as a plant, in it contained alkaloids and the utilization of tobacco in the theoretical part. In more detail it deals with the production and construction of cigarettes which is closely related to the content monitoring of total alkaloids in tobacco. The contents of total alkaloids are determined by the continuous flow analyzer- SKALAR. On this spectrophotometer are set the contens of reducing sugars as well. The comparison of total alkaloids contents and reducing sugars from the perspective of single tobacco types, countries of cultivation and crop years is clearly summarized in the experimental part of the thesis that was performed in the company Philip Morris ČR, a.s.
Whey utilization with thermophilic microorganisms
Rychová, Alexandra ; Vítová, Eva (referee) ; Babák, Libor (advisor)
This diploma thesis studies the utilization of whey using thermophilic bacteria of the genus Thermus and Geobacillus. The whey stripped off proteins was used as a cultivation medium during experiments. The cultivation took place in the Erlenmeyer flasks, to assess the optimal conditions for microrganism’s growth. During the cultivation in the bioreactor, growth curves were established. The amount of whey utilization was assessed by analytical methods that determine the concentration of reducing saccharides (lactose) and chemical oxygen demand (COD) while studying the optimal conditions and a method determining the concentration of reducing saccharides during growth curves analysis.
Analysis of selected biologically active substances in cereal products
Skutek, Miroslav ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis was focused on study of biologically active compounds, especially some sugars in cereal products. In experimental part the total of 29 different cereal materials, food industry waste products and natural complex matrixes (microbial polysaccharide, honey, beer) were used. As a part of this work optimization of analytical methods suitable for analysis of simple sugars, oligo- and polysaccharides was done. In cereal samples reduced and neutral sugars were analyzed spectrophotometrically and individual sugars were detected by chromatography. For HPLC/RI analysis optimal mobile phase composition and chromatography conditions were proposed. For mono- a oligosaccharides C18-NH2 sorbent, mixture acetonitril:water 75:25 as mobile phase and flow 1 ml/min were verified as suitable separation parameters. Thin layer chromatography of mono- and oligosaccharides was optimized too. Introduced chromatography and spectrophotometry methods were then applied to analysis of cereal samples. As a model sugar natural microbial polysaccharide pullulan was used to analytical method testing. In cereal products and food matrixes total neutral and reduced sugars as well as products of their acid and enzyme hydrolysis were measured. Detailed analysis of some glycoside composition was tested too. As the most usable method for both qualitative and quantitative analysis of cereal sugars HPLC/RI method was found. To detailed identification of malto-oligosacharides tandem LC/MS/MS technique using derivatization by 1-phenyl-3-methyl-5-pyrazolon was tested too.
Basic chemical characteristics of juices of selected white gooseberry varieties
Zelníčková, Jaroslava ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Theoretical part of this bachelor thesis includes taxonomical classification of gooseberry, deals with biological characteristics, active substances contained in fruits of gooseberry and its using as well with description of the methods by research detection. In the experimental part primary nutritional parameters of chosen gooseberry species were analysed including orientation juice yield, soluble solids, pH, dry matter, titratable acids, formol number and reducing sugars. There were analysed following species of gooseberry: Reflamba, Mucurines, Rixanta, Veliš, Citronový obří, Darek, Prima, Invicta, Zlatý fík a Zebín. Individual species and cultivars were compared based on the results.
Basic chemical characteristics of juices from selected red currants varieties
Rucká, Markéta ; Jurečková, Zuzana (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis is focused on the determination of basic chemical characteristics of selected red currants varieties from the Research and Breeding Institute of Pomology Holovousy Ltd. The theoretical part concentrates on general information about red currant, such as history of cultivation, origin and its expansion. There is also mention of the general characteristics of currant, currant building and significance of red currant cultivation. Chapter "Individual varieties" deals with the analysed varieties of red currants, especially its description and its biological properties, followed by an overview of the main substances contained in red currants and their brief description. Bachelor thesis also presents examples of the processing and the utilization of red currant in the food industry. The final chapter provides information about the individual determinations of the chemical characteristics of red currants, which include juice yield, soluble solids content, total dry matter content, pH, titratable acidity, formol number and reducing sugars. The experimental part describes the specific conditions and methods of individual determinations, followed by a summary of the results and their discussion. Variety Jesan showed the highest juice yield (63 ml per 100 g) and the highest pH value (3,16). The highest soluble solids content (13,94 %) and the highest formol number (22,83 ml of 0,1 M NaOH per 100 g) was determined in a variety Jonkheer van Tets. The highest dry matter value was detected for variety Rovada (14,48 %). The titratable acids content was highest in variety NŠLS 11/6 (403,88 mmol•kg-1). The highest concentration of reducing sugars was found in variety Tatran (8,17 %).
Basic features of wine fermented from freerun and pressed must
Becková, Eliška ; Šalplachta, Jan (referee) ; Vespalcová, Milena (advisor)
My work is engaging in winemaking of white and red wines. Theoretic processes and goings during winemaking is describe in the first part of this work. It deals harvest of kapes, fermetation, clearing wine, chemical content of grapes and wine, deseases and abnormality of wines. There are this described choosen variettes, their grapes were processed practically. The third part of this work is dealed in practice winemaking and chemical analyse sof wines. Musts from the start of pressing, from the first dressing and from the end dressing fermented to the end dressing . They were fermented and than analysed by chemical and tasting tests. The discussion about the dependence of the quality of wines on the kind of the must during pressing is presented in the end of this work. The results are motivated by chemical analyses and senzoric tasting of the experts.
Monitoring of the selected parameters of grape wine before expedition
Trávníčková, Jiřina ; Pořízka, Jaromír (referee) ; Omelková, Jiřina (advisor)
Presented bachelor thesis is focused on laboratory monitoring and determination of the selected parameters of grape wine which includes specific gravity, alcoholic content, reducing sugar content, total titratable acidity, volatile acidity and total solids, sulfur dioxide content and protein and crystalline wine stability. The theoretical part deals with the wine production technology from the entry commodities to the bottling of mature wine. The aim of experimental part is a description of analytical determinations and complete wine sample analysis according to Regulation EEC No 2676/90 determining Community methods for the analysis of wines.
Biologically significant substances in cereal products
Vondráčková, Hedvika ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
Presented work was focused on study of biologically significant substances in cereal products. In experimental part selected active substances in cereal bars were analyzed. The highest content of total phenolics, total flavonoids, total antioxidant capacity, procyanidin B2 and chlorogenic acid was measured in plums and blueberry bars. The highest level of reduced saccharides was evaluated in raspberry and cereal bars. Presence of main simple sugars - maltose, glucose and fructose was detected in all bar samples.

National Repository of Grey Literature : 34 records found   beginprevious25 - 34  jump to record:
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