The diploma thesis "Determination of aflatoxin in selected products" deals mainly with aflatoxin, its occurrence in raw materials of plant origin and methods of decontamination. The studied toxin is produced by fibrous micromycetes primarily from genus Aspergillus is their secondary metabolites. It is very widespread and is a frequent cause of retention of raw materials at the border. Factors that affect production of aflatoxin are, among other things, water activity and pH and are also determined in samples and mentioned in theoretical part. A total of 30 samples were tested for aflatoxin B1, including batch of apricot jam, two batches of Svatojánské ořechy and two batches of Jarní hustopečské mandle. A heterogeneous competitive enzyme immunoassay (ELISA) was used for the analysis. Detectable amounts of AFB1 in the range of 1,26 - 1,66 μg∙kg-1 showed 26,67 % of samples. These values were determined in samples of Svatojánské ořechy and Jarní hustopečské mandle, the apricot jam did not contain measurable amount of AFB1.

The Shea nut and butter production industry has been a prominent feature of the economy of northern Ghana, dominated by women. Recent surge in international demand for the commodity has led to the claim that the local industry possesses the potential to alleviate poverty. This study has employed the Global Value Chain analysis together with the New Institutionalism theory to assess the socioeconomic importance of shea nut and butter production on the livelihoods of the people in northern Ghana. Given the significance of value chain governance on resource accumulation and distribution as well as opportunities for upgrading, market access and …the study focused particular attention on the effects of chain governance on the shea industry in northern Ghana and how that impacted the socioeconomic lives of the people. The study found that the shea industry provided employment and a source of income to the people especially women who dominate the sector. However, the incomes levels from shea are so low as to make any significant improvements in the lives of domestic actors especially those at the low end of the chain ie nut collectors and butter processors. The the challenges identified were the mode of insertion in GVC, the lack of institutions especially, an effective regulatory body to oversee the sector and a general reluctance of the government to invest in the sector by providing the necessary infrastructure to improve the industry. In addition, value chain governance has enabled a few leading downstream shea processing firms and product manufacturers to dominate the industry through their agents who have been indulging in exploitative activities thereby reaping huge profits at the expense of the low end actors. It is the recommendation of this study that the state should get actively involved in the management of the industry by setting up a regulatory body which will oversee the activities of the sector. Such a body should be de-coupled from the COCOBOD in order to move the industry from being under the shadow of the Cocoa industry. The extortionist and exploitative activities of some profit making NGOs, Development Agencies and Large scale shea nut and butter exporters should be checked so as to free the shea worker from being cheated.

The thesis deals with determination of selected nutrients (copper, zinc, iron) in nuts. In total, 33 samples, bought in retail chains in Czech Republic, were analysed. The theoretical part of the thesis is focused on characterisation of individual nuts including other fruits, which are consumed as nuts. In the practical part, contents of copper, zinc and iron were measured by the atomic absorption spektrometry method. From the results, it is clear that the highest amount of copper was found in Brazil nuts. The lowest amount of copper was found in macadam nuts. Overall the highest content of zinc within all types of nuts was found in pine nuts and the lowest amount of zinc was determined in coconut and edible chestnuts. Iron was the most contained in alaburks, cashews and pine nuts. The lowest quantitty of this element was measured in edible chestnuts.

This thesis is engaged chip machining using the system Sinumerik 840D-ShopTurn. The first part of the thesis is engaged the incorporation of the control system Sinumerik 840D - ShopTurn among other control systems. The thesis also deals with the basic methods of NC programming with an emphasis on workshop-oriented programming. The practical part includes design and preparation of technical documentation for the selected part (nutcracker), including creating a CNC program using workshoporiented environment - Sinumerik 840D ShopTurn. The program was validated using a graphical simulation software SinuTrain 7.5 and also directly at the machine SP 280SY. At the conclusion was created techno - economic evaluation of the proposed technology.

The aim of this study is to determine the content of toxic and essentials elements in samples of nuts and seeds produced by ecologic agriculture and to compare results with nuts and seeds from conventional agriculture production. These nuts and seeds can be bought in the Czech market (except bio pine nuts, bio pecan nuts and bio pistachios). The amount of elements was analysed using inductively coupled plasma mass spectrometry after previous digestion of samples using microwaves. This study summarizes the main physiological functions of toxic and essentials elements. Results were also compared with another studies. It does not results from all measured amounts of all essential elements, that bio nuts and seeds have higher amounts of these elements; however, all amounts of toxic elements in bio nuts and seeds are lower than in the no-bio ones. For more precise results it would be necessary to measure more samples.