|
|
The quality of eggs - general, functional and nutritional properties
PECH, Miloslav
This bachelor's thesis, processed in the form of a literary review, focuses on a comprehensive view of hen's eggs, analyzing their general, functional, and nutritional properties. After the introduction, a literary review follows, mapping the biological origin and domestication of the chicken, and then summarizing the current state of chicken farming. The thesis then delves into the formation and development of eggs, examining the structure and chemical composition of the yolk and albumen, including their proteins, lipids, carbohydrates, pigments, vitamins, and minerals. The physicochemical properties of eggs are also analyzed, including a total of seven properties such as specific gravity, freezing point, or refractive index. A detailed examination of the functional properties of eggs follows, which represent a key element in understanding their wide use in the food and culinary industries. The thesis focuses on analyzing the mechanisms through which hen's eggs can form gels, foams, and emulsions, which are properties that play an important role in various food processes and recipes. These properties are essential for the production of various foods, such as gelatin desserts, leavened doughs in baking, sauces, and mayonnaises. Eggs are also recognized as functional food because they are a rich source of nutrients, including vitamins, minerals, and biologically active substances that can contribute to overall health. These substances can, for example, help reduce the risk of heart disease and improve eye health. In the next section, the thesis focuses on the nutritional properties of eggs, examining microbial contamination, egg allergies, and biologically active substances such as choline, immunoglobulin Y (IgY), and lutein and their impact on human health. An overview of this section provides a deeper understanding of hen's eggs and their influence on human nutrition and health.
|
|
|
Vlastnosti vaječných hmot využitelných jako nutričně obohacující složky potravin
Fikarová, Zdeňka
The diploma thesis deals with determination of pH, viscosity, whipping, strength and height of the white gel and the strength of the bakery product with added egg materials. Various additions of salt, sugar, citric acid, triethyl citrate, soy lecithin, corn syrup, whey protein and apple pulp have been added to the egg masses. The index of whipping with different additions ranges from 300 – 600 % for hen eggs and ranges of 256 – 680 % for quail eggs. The index of foam durability for 30 minutes with different additions ranges of 73.83 – 99.83 % for hen white and 69 – 99 % for quail white. The index of foam durability for 60 minutes ranges of 71.94 – 98.62 % for hen white and 67 – 97 % for quail white. The strength of the laboratory egg white gels ranged between 1.61 – 8.10 N and the commercially purchased gels ranged between 7.78 – 19.16 N. The strength of the bakery product with various additives ranged from 2.54 – 9.43 N in hen eggs and in the range of 5.85 – 9.65 N in quail eggs. The viscosity at a shear rate of 1 s-1 ranged between 187.5 – 1259.5 mPa•s for hen's egg whites and ranged of 303.5 – 1045.7 mPa•s for quail whites. Various additives can influence the technological properties of both hen and quail eggs.
|
|
|
Kvalitativní parametry vajec minoritních druhů drůbeže
Fikarová, Zdeňka
This bachelor thesis concerns with the issue of the quality of eggs of minority species of poultry´s - duck´s, goose´s, turkey´s, quail´s, ostrich´s, emu´s, guinea fowl´s and pheasant´s eggs. The world production and the consumption of egg from minority species of poultry´s is rising. Chemically, the eggs differ in ratio of egg-white, yolk and egg shell, but as well in the content of water, proteins and lipids. The highest content of water is contained in ostrich´s eggs, the goose´s eggs contain the highest content of proteins, and the duck´s and emu´s eggs contain the highest content of lipids. As well, it can distinguish their smell, taste, colour of the shell and colour of the yolk. According to their physical qualities, the eggs differ for example in their weight - ostrich´s egg is the heaviest (1 520 g), on the other hand the quail´s egg is the lightest (11 g) - or in their yolk index - the pheasant´s and quail´s eggs have the highest value (50%), the emu´s eggs have the lowest value of the yolk index (31%).
|
guest ::
