No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

The aim of this work was to suggest a quicker, technically-undemanding, and easy to use method for measuring the malt colour without congress mashing, and to evaluate the extent how the colour values obtained by this quick method will vary from the values obtained by a standard method. 12 malt samples were used for the experiment (3.1 -- 1320 j. EBC), wort was prepared from them in the standard (congress) way and in the new quicker way. The quick method for wort preparation was based on the extraction of overground malt in hot water. The extraction lasted 5, 10, and 15 minutes. The following properties of wort were measured by the spectrophotometer: clarity (L*) a* and b*. Overall differences in the clarity (L*) and calculated total colour difference (delta E*) between the wort prepared by the tested method and the congress wort were caused by the fact that boiling water, which created conditions for Maillard reactions, was used for the extraction. High-molecular colour components started to be formed in the extract. The suggested method seems to be applicable, but it will be necessary to optimize its conditions, especially to decrease the water temperature for extraction.

The aim of this thesis was to compare the analytical and sensory attributes of wines aged in different storage containers for a certain period of aging . The theoretical section describes wine storage containers from history to the present, their advantages and disadvantages. There are more details of barrique barrels , their processing and burning . The following section discusses the selection of appropriate containers for alcoholic fermentation. There is an important process of biological degradation of acid before red wine maturing, which is described in the next chapter. A large part of the chapter is devoted to wine aging . There are some effects in terms of oxygen, depending on maturation, pH for red wine colours, pH of the acid. An important chapter is the aging of wines in barrique barrels , followed by a change of phenolic compounds, dependence of oak and volatile compounds on physico -chemical characteristics of wines. In subsequent chapters there is explained the concept of wine aging , there are cataracts, diseases and defects of wines that may occur during aging . In the experimental part I used two red wines and one white wine . Wines were divided into inert containers and various barrels of different manufacturers and volumes. Red wines were produced in the same technology manner and the aging conditions (temperature , humidity) were the same as well. The aim was to evaluate the analytical and sensory values of wines for the time of one year . The attempt for white wine was aimed for the time of three months. The main intention was to monitor changes in the content of phenolic compounds : polyphenols, anthocyanins , polyphenols amount of gallic acid, hydroxycinnamic acids and flavonoids. Differences for each wine were observed depending on the container size and the ripening time. The senzory evaluation was an important parameter. Wines matured in barrels showed aromatic complexity and tannin structure with finesse .