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The importance of milk and diary products in human nutrition
Maroušková, Nela ; Hejtmánková, Alena (advisor) ; Michlová, Tereza (referee)
Milk and dairy products become integral part of human nutrition and belong to common food. Milk is very valuable because it contains complete proteins. Its disaccharide lactose is a source of energy. Butterfat is easily digestible. Besides potassium, sodium, magnesium, chlorine and sulfur milk contains also dietary elements like calcium and phosphorus.
Milk also contains many trace elements like iron, zinc, iodine, selenium, manganese, fluorine, chromium, cobalt, and molybdenum. Milk is an important source of vitamins. It contains significant amounts of water soluble B and C vitamins alongside fat soluble vitamins E and A and smaller amounts of vitamins K and D.
Milk and dairy products are an important source of calcium. Lack of calcium is the main cause of osteoporosis. Regular consumption of milk and dairy products may reduce the risk of cancer. Nevertheless disproportionate consumption of dairy products containing unsaturated fats can lead to higher incidence of certain types of cancer, higher risk of cardiovascular diseases and metabolic syndrome. Milk contains also compounds that prevent aforementioned diseases.
Milk is the only source of nutrients for newborn children and suckled infants. It is convenient source of nutrients in times of higher nutrient demands especially during pregnancy, nursing and senescence.
Milk, milk cream, fermented milk products, buttermilk, cheese, whey, curd cheese, whey proteins, frozen creams, cream, condensed and powdered milk belong to most important products. Fermented milk products are very beneficial to human health. Those products are sources of complete proteins, calcium, phosphor and vitamins, especially B vitamins. Lactose is decreased making fermented milk suitable for lactose-intolerant subjects. The fermentation process increases the shelf-life of the product while improving the digestibility and microbiological safety.
Milk and dairy products consumption can also have negative impact on human health. Lactase deficiency or lactase insufficient activity in small intestine results in lactose intolerance. Milk can also cause food allergy to the cow's milk.
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The importance of vitamin D and calcium in the human diet
Bártová, Magdaléna ; Hejtmánková, Alena (advisor) ; Michlová, Tereza (referee)
Vitamin D refers to a group of fat soluble steroids. The most important forms are
cholecalciferol occurring in foods of the animal origin and ergocalciferol of the plant origin. Human
accept them in the diet; the fatty fishes, fish liver, and some other foods like milk, eggs or yeasts are
rich resources of vitamin D. Unlike the other vitamins, the synthesis of vitamin D can also take place
in the living body. Cholecalciferol is formed in the skin from its precursor 7 - dehydrocholesterol by
the effect of UVB radiation. The conversion efficiency depends on various factors.
Two successive reaction steps are necessary for the activation of vitamin D. The first step of
hydroxylation occurs in the liver to be formed calcidiol. Calcidiol is the principal form of vitamin D in
the blood acting also as the indicator of body supplies. The second one takes place in the kidneys
where calcidiol is transformed to calcitriol. Calcitriol is assumed as the active hormonal form of
vitamin D binding to the receptor for vitamin D - VDR. The best known and the most explored
function is the effect of vitamin D on the calcium and phosphorus homeostasis. Consequently, vitamin
D also influences the proper functions of muscles and the immune system. It reduces the risk of the
cancer and cardiovascular diseases by various mechanisms as well. However, there are assumed
another effects of vitamin D on the human body, which are not fully yet understood and are the subject
for further research.
Calcium constitutes the major mineral component of bones and teeth. It is an essential nutrient
and therefore it is necessary to supply it with food. Its content in foods is various as well as its
usability from these. The major resources of calcium are milk and dairy products. Calcium is also
present in eggs, mineral waters, certain fishes and food of plant origin. Especially, the plant resources
usability of calcium is limited because of the insolubility of some calcium complexes. Calcium is
essential for the composition structure of bones and teeth. Besides of structural function, it has a main
role in the blood coagulation, neuromuscular transmission or muscle contraction.
Vitamin D has an influence on the usability of calcium because of the efficiency increase of
calcium absorption in the intestine. The lack of both micronutrients leads to skeletal diseases -
osteoporosis, osteomalacia and rickets. The adequate intake of both essential part of food, vitamin D
and calcium, is important especially for the growing children, elderly people, and pregnant and
lactating women.
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Legislative requirements for milk quality in the Czech Republic
Škvorová, Kamila ; Hejtmánková, Alena (advisor) ; Michlová, Tereza (referee)
The aim of the thesis was to give a comprehensive review of literature dealing with legislative measures, milk production in terms of sales of milk and its storage. We used the most current Czech and European legislation. These sources have been supplemented thematically compliant scientific and professional publications.
Milk is a primary since the Middle Ages and sought food which people consume every day. Along with dairy milk a deserved popularity mainly due to its rich composition and nutritional and health properties. The main components of milk include water, lactose, fat, protein and minerals. Milk however can also include foreign substances of organic and inorganic origin and unwanted microflora. Microorganisms are particularly dangerous to humans and are considered a major source of foodborne illnesses. To eliminate unwanted microflora, extending shelf life and maintain public safety is used heat treatment, including pasteurization and treatment of very high temperature (UHT). This treatment must be carried out according to established requirements and specifications.
If a consumer buys a dairy product in the Czech Republic retains its quality as well. All animal products, including products imported to the Czech market, are compulsorily fitted with oval health mark, which ensures wholesomeness. The quality of the milk is influenced by many factors, most of which are closely linked, and therefore not always easy to identify the specific cause possible reduction in quality standards. Already during the production process, emphasis is put on prevention in the field of quality and safety. Security is guaranteed by a system of determining critical control points HACCP, which is in the Czech Republic and the EU compulsory by law. Among the optional systems include ISO. Most enterprises with good reputation has introduced both these systems. Simultaneous application of HACCP and ISO standards provides a guarantee for the security of the overall quality and safety of products. This connection is known as TQM system.
The main indicators of quality of raw milk are total number of mesophilic microorganisms, somatic cell count, fat content, crude protein residues of inhibiting substances, the average herd size and the number of bred cows. The milk must not contain any preservatives or stabilizers. Meeting the requirements and quality criteria will be checked on the appropriate number of samples that are collected in enterprises producing milk, random checks.
The basic quality criteria of raw milk, food business operators must ensure that:
The content of microorganisms in 1 mL at 30 ° C must be < 100 000. It is found average values for two months for the collection of at least two samples per month.
Somatic cells in 1 ml at 30 ° C must be < 400 000. It is obtained by moving the geometric mean for the three months, every month, evaluates at least one sample.
Immediately before treating the milk must contain 1 ml < 300000 microorganisms at 30 ° C. In the treated milk that is used for the manufacture of other dairy products, may be the content of microorganisms in 1 ml> 100,000 at 30 ° C.
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