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This Master's thesis is focused on evaluation of qualitative characters of cow's, sheep's and goat's milk and its different sensory quality. The theoretical part describes in detail every characters of milk as a fat, proteins, carbohydrates and also will focused on extension of quality of milk using thermo-adjustment and focused on basic sensory evaluation of certain characters, including the most frequent deviations from standard state. In the practical part is summary of results from sensory evaluation of many varieties of milk with different thermo-adjustment or following thermo-adjustment in households consecutive years 2010--2013.

In the last ten years can be recorded a multiple number of minibreweries, called sometimes craft breweries I tis not caused only by demand of kinds of beer characterised by special types of beer styles, but as well by the fact, that they are not anyway regulated and keep their natural taste and smell. The problém of unregulated (unfiltered and unpasteurized) beers starts by the contamination during their production and it may cause their relatively fast spoiling. Shelf life of these beers is e few weeks only. The time of their minimal shelf life is influenced by a lot of factors content of alcohol, rest extract and mentioned extent of contamination. The breweries called as industrial or commercional treat their beers by pasteurization or filtration which cause inactivation or killing of the microorganisms or their elimination. These beers are microbiologically stabile, they are not liable to quick spiling and i tis possible to insure their longer shelf life. Pasteurized a filterd beers show changes in their sensorial character. The aim of this diploma thesis was to determinate the condition of flash pasteurization of unfiltered beers with the aim of microbiological stability and simultaneously no changes of their sensorial quality. The experiment is finally in treatment unfiltered beer by differnt dosing of pasteurization units and following microbiological analysis, able to demonstrate the stability effect. The analysis were used with unfiltered and unpasteurized beers and with unfiltered beers where the pasteurization doses 20 PU, 30 PU, 40 PU, 60 PU, 80 PU and 100 PU were used. The idividual parameters were watched within the horizont of 4 months. The part of these tests was even microbiological analysis of the rinse water. Another task was to find out the dates from the microbiological controls of beer in selected small breweries, which use in order to heighten of microbiological stability, different kinds of filtration, to verify their effectivity and to appreciate their acceptability for minibreweries. The test showed the effectiveness of pasteurization of unfiltered beer with the rations 40 PU minimally. Where higher ratins were used could be seen apparent sensorial changes. The pasteurization of unfiltered beers are for craft breweries useful only in case of higher production of bottled beer or beer for export, because the financial expenses bound with provision flash pasteurizer are to big and for minibreweries mostly limiting. The kieselguhr filtration as well the ultrafiltration are for minibreweries unusefull, as they could not be able to insure such conditions that provide their proper affectiveness.

Alkaline phosphatase as an indicator for the heat treatment of the milk for cheesemaking Summary The aim of this diploma thesis was to summarize current knowledge about the evaluation of alkaline phosphatase activity as an indicator of heat treatment of milk for production of dairy products in theoretical part. In experimental part were comparised 2 methods for this enzyme activity determination, the original according to ČSN EN ISO 11816-2 (2003), using pasteurized milk as an extracting agent, and ISO 11816-2/IDF 155-2 (2010), using extraction buffer. For comparison were used 110 cheese samples, 8 quarg products, 49 fresh cheese products, 9 spiced fresh cheese products, 7 white-brined cheese products, 7 Penicillium sp. flora cheese products, 5 coryneform flora cheese products and 25 semi-hard and hard cheese products. Alkaline phosphatase (EC 3.1.3.1) is a hydrolase cleaving phosphate groups at the 5th and 3rdposition of many molecules including especially nucleotides and proteins. The enzyme has a pH optimum in the alkaline range (pH 10), their cofactors are ions Zn2+and inhibitors Cu2+. Dairy alkaline phosphatase derived from mammary epithelium and other cellular residua in milk. In this medium is the enzyme localized on the membrane of fat globules. Their amount depends on the stage of lactation (the highest concentration is in colostrum) and animal health (their concentration increases when disease, especially mastitis, starts). Due to its specific thermostability is alkaline phosphatase used for proof of milk and milk products pasteurization. In the experimental part of the diploma thesis was found that the recommended substitution of pasteurized milk for buffer improves enzyme extraction process from cheese matrix and so enhances method sensitivity (p > 0.05). Method unsuitability for Penicillium sp. flora cheese (especially for blue-veined ones) was also confirmed (p > 0.05). This unsuitability could be explained by content of microbial alkaline phosphatase. For the same reason might not be this method suitable also for coryneform flora cheese. On the contrary, this analysis is suitable (p > 0.05) for white-brined cheese. For spiced fresh cheese were the results in terms of evaluation suitability ambiguous. Based on the obtained data was also confirmed the suitability of proposed limit (10 mU/g) for residual enzyme activity in products from pasteurized milk.

The aim of this work was to go thoroughly throw the already existing HACCP system in the company and to evaluate if the hazard is treated in a good way and to find other more effective approach to prevent the hazard. An effort was focused on the primary processing milk and on the process of the treatment of acidified milk products. While investigating current condition the author has made several experiments focusing on the settled conditions of important process in the production (for ex. pasteurization). Chemical, physical, qualitative and microbial properties were observed on a concrete diary product. The main investigation {--} the simulation of disturbance of the cooling chain - was performed where products were exposed to various temperatures for various time periods. During this test were observed: the temperature, pH and microbial changes in exposed products. Due to results form all observations that where performed in this research its possible to proclaim that the HACCP system is settled in a good way and even if above mentioned situation happen the product is safe.