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The lipid quality of our economically significant fish species
KREJSA, Jakub
The level of fish consumption in the Czech Republic is very low. One of the possible factors influencing this situation is low awareness of the customer or consumer. The thesis "The Lipid Quality of our economically significant fish species" works with the list of nineteen economically most significant fish species not only including fish from the semi-intensive and intensive breeding, but also such species that are interesting for the consumption from the sport fishing point of view. The samples taken from particular fish were primarily used for the analysis of the fat content and fatty acid composition. The analysis established very interesting results in this field and created basis for further analysis for establishing atherogenic and thrombogenic index or for formation of nutritive values mentioned as "Big 7" (fat content and the ratio of fatty acid out of it, sacharide content and the sugar ratio in it, protein content, ash content and energy value) by particular fish species according to the regulation ES 1169/2011. The results of this work confirmed that the fat content and its composition are highly influenced by the type of ingested nourishment. The fish bred in semi-intensive way with the highest fat content are Common carp (7,62 ? 2,9 %) and Silver carp (6,87 ? 1,37 %). On the contrary the predatory fish evinced the fat content usually within 1%. The fish from extensive breeding or the types caught in sport fishing are in the fat con-tent more balanced. The fattest fish in this group is Silver Bream (5,52 ? 0,44 %) and the lowest content evinced Goldfish (1,14 ? 0,38 %). Also the species living in the aquaculture and living in the free waters as well were compared (Common carp, Rainbow trout, Peled, Tench, Wels catfish). The fatty acid composition significantly depends on the fat content. The predatory fish contain 195 - 219 mg×100 g-1, the most (p0,05) was found by the peled from the extensive breed (1048 mg×100 g-1 EPA + DHA). The participation of SFA by the most of the fish was under 30%, the content of MUFA was the highest by the Common carp (52,71 ? 7,75 %), the lowest by the European perch (18,83 ? 1,12 %). Pike, Zander and European perch contain relatively the most of PUFA, this is over 50%. All the fish species (Nile tilapia excluded) show in this study the values of atherogenic index below 0,5 and thrombogenic index below 0,4. The total energetic value was counted from the results of nutritional values presented in the "Big 7" list. The higher energetic value is directly proportional to the increasing fat content. The fish species included in this thesis show the total energetic value in the range of 500 - 900 kJ×100 g-1. The results of this study bring complete, laboratory proven information about the nutrition composition of our fish. This data can be appli-cable not only to increase the knowledge of the customers but mainly to be used by breeders and manufacturers of fish as an implement of fulfilling the duty of stating the nutrition facts on their products according to ES 1169/2011 on the providing infor-mation about the eatables to the consumers.
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Rol of sacharides in nutrition
JURÁK, Ondřej
In the theoretical part of the bachelor thesis basic characteristics of the sacharides were handled by form of literary searches. Further, the properties of basic cereals and cereal products were described, including the chapter about digestion and absorption of carbohydrates in the human organism. Last part describes cereal products, especialy breakfast cereals, their prevalence and importance in the diet of school pupils and students. The aim of the research part of the bachelor thesis was to realize and analyse a questionnaire survey in the segments - pupils of higher grades of elementary schools and students of universities, focusing on the validation of the knowledge about carbohydrates, cereals and its consumption. The first partial aim was to determine the interest of pupils of higher grades of elementary schools and students of universities in different kinds of cereals products. The second partial aim was the comparison of the dieatary habits of pupils and students. On the basis of targeted objectives, three working hypotheses were formulated and verified. The validity of the first hypothesis - pupils of the second level of elementary schools have less knowledge about carbohydrates and cereals products than the students of universities, was confirmed by the analysis of responses from the questionnaires. The validity of the second hypothesis - students of universities prefer breakfast cereals more than pupils of higher grades of elementary schools, has also been confirmed. During the analyses of answers related to the third hypothesis - pupils of higher grades of elementary schools have better forenoon eating habits, than students of universities, it was found that students of universities have better eating habits than pupils of elementary schools, however pupils have better eating habits during snacks.
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