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Tea or coffee?

CaffeinecaffeineCaffeine is a white, odourless substance, sparingly soluble in water. This compound is also a component of energy drinks, cola drinks, chocolate and Kola nuts. Caffeine is rapidly absorbed from the digestive tract and is excreted in the urine.

Caffeine stimulates the cerebral cortex, improves the efficiency of thinking, speeds up heart action, and improves well‑being. Its effect on the body depends on body weight. Excessive intake of caffeine (above 2000mg) can cause insomnia, impaired motor coordination, increased breathing rate and general anxiety.

Other compounds contained in coffee, such as polyphenols, antioxidants, have a beneficial effect on the body, because these slow down the aging process, prevent the accumulation of cholesterol, protect against atherosclerosis. Coffee ingredients can also act adversely, because they stimulate the secretion of hydrochloric acid in the stomach, causing heartburn in many cases. Coffee can contribute to bloating and indigestion, increasing the risk of colon cancer. An important disadvantage of coffee is its irritating effect on the digestive tract. The lethal dose of caffeine is about 10 g (depending on body weight). Getting out of caffeine addiction is linked with headache, irritability, lack of energy and drowsiness.

Caffeine belongs to the alkaloid group (a group of organic compounds, usually of vegetable origin, containing nitrogen and having a strong effect). Some of the alkaloids are used as medicines, others are poisons.

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Ilustracja przedstawiająca zrośnięte roślinnością pole uprawne na terenie górskim z licznymi pagórkami i dolinami. W oddali widać szczyty gór, porośniętych drzewami.

Tea (mainly white and green) contains significant amounts of compounds that support the body's natural defence mechanisms, counteract cancer. These compounds are called antioxidants because they inhibit the body's oxidative processes. Its activity is due to i.e. unique amino acid – theanine contained in it. The most of this ingredient is contained in green tea – 100 g of dried leaves contains 0.6–2.3 mg of theanine. TheaninetheanineTheanine influence on the taste of tea. Interesting is the physiological activity of theanine – it lowers blood pressure, has an effect on information transfer and brain function, has a calming and relaxing effect.

Other important components of tea are:

Caffeine – initially, it was mistakenly thought that tea included a compound with caffeine‑like properties and structure, which was called theine. Currently, it is already known that the compound is simply caffeine.

Flavonoids (polyphenols)flavonoids (polyphenols)Flavonoids (polyphenols) – have strong antioxidant properties and the ability to bind metals, due to which these helps to protect the body against harmful free radicals.

Tea also contains some vitamins: A, B1, B2, C, E and K and mineral compounds of: fluorine ions, calcium ions, iron ions, potassium ions, sodium ions, zinc ions.

Tea is a beverage with high health‑promoting properties, but it can also work unfavourably.

• Consuming too much tea (more than 4 cups a day) can make the tannins contained in it irritate the mucous membrane, which will adversely affect the absorption of nutrients. In addition, an excess of tannins destroys vitamin BIndeks dolny 1₁.

• Polyphenols in tea can block the absorption of iron compounds from meat and fish. Therefore, people suffering from anaemia should not drink tea with food. To neutralize this effect, foods rich in vitamin C should be consumed to increase the absorption of iron ions.

• Drinking too much tea (especially strong) before bedtime can cause insomnia.

Mineral water, spring water or maybe cola?

Spring waters come from underground deposits. These contain only a few minerals that are important for human health. Very low mineralization (up to 500 mg of minerals/l) are the cause why such waters have a high degree of assimilability, which results in leaching healthy minerals from the body. Excessive consumption of such waters at one time may cause disturbances of the body's water and mineral metabolism.

Mineral watersmineral watersMineral waters come from shallower underground intakes than spring waters, so they are richer in minerals. These can be medium mineralized (500–1500 mg/l) and highly mineralized (over 1500 mg of mineral substances/l). Regular consumption of approx. 1 litre per day of certain mineral waters, e.g. with high (or) low ion sodium content or high content of ions of magnesium and calcium, may improve some of the body's physiological functions. Systematic drinking of waters containing a significant amount of ions of calcium and magnesium in quantities of 0.5–1 litre per day improves the balance of these elements in our body.

Table waters are enriched with the most needed minerals, especially ions of magnesium, calcium and iodine (mineralized). These can be a very important supplement to the diet, especially in areas where there are no natural mineral waters. Such waters are hard waters and have beneficial effects on the heart. People who often drink water containing a lot of ions of magnesium and calcium, protect their body against cardiovascular disease and heart attack.

Medicinal waters (available in sanatoriums and pharmacies) support the treatment of various diseases. Depending on the composition and mutual proportions of their components, these improve metabolism, relieve stomach discomfort, help to cure kidney diseases and fight diabetes. Medicinal waters do not quench thirst and should only be used as directed by the doctor. It should be remembered that medicinal waters act as a medicine and they must not be overdosed, as these may have harmful effect.

Cola and other still and sparkling sweetened beverages do not have nutritional values, and their main advantages are the taste associated with high sugar content. Obviously, these fulfil the basic function for beverages – they provide water. However, consuming a large amount of this type of beverage can adversely affect our health. The carbon dioxide contained may cause flatulence and high sugar content lead to obesity. The acid pH of carbonated beverages adversely affects the condition of the teeth, and the presence of phosphoric acid increases the risk of osteoporosis incidence, i.e. loss of bone mass.

Energizer or isotonic drink?

Energizers (energetic drinks)energizerEnergizers (energetic drinks) are intended for people whose energy demand is higher than average. Their action is based on improving the concentration and efficiency of the body, in addition, these accelerate metabolism.

These beverages include mainly caffeine. The other ingredients are taurine, B vitamins, various herbs and sugar. This composition is supplemented by water, carbon dioxide, acidity regulators. The high content of some ingredients in beverages can be dangerous – especially when consumed by children or pregnant women – this is the case with caffeine and B vitamins. Typically, energy drinks contain caffeine in the amount of 32 mg/100 ml and significant amounts of B vitamins.

For this reason, you should drink them with caution. This is particularly important because the consumption of excessive amounts of caffeine does not improve sport performance, but has adverse side effects.

The main components of isotonic beverages are water, carbohydrates and sodium chloride.

Juice, nectar or fruit flavoured drink?

Fruit juices are a source of many vitamins and mineral salts, necessary for proper development and good health. Juices and nectars enrich the human body with such essential nutrients as: pro‑vitamin A, vitamin PP, vitamin C, vitamin E, potassium ions, fibre, pectin, and folic acid.

Fibre is a non‑digestible carbohydrate. It does not have nutritional functions, but it is beneficial in human diet because it speeds up intestinal peristalsis, regulates defecation and reduces the absorption of cholesterol.

It is worth knowing that:

• one glass of carrot juice (200 ml) covers the average daily requirement for vitamin A;

• two glasses (200 ml each) of orange juice or blackcurrant nectar cover the daily average requirement for vitamin C;

• one glass of tomato juice provides an average of 500 mg of potassium compounds, which satisfies on average 25% of the daily requirement.

Maybe milk?

Drink milk–you will be great– it is widely believed that after breastfeeding, the diet of a child or young man there must include cow's or goat's milk. It is believed that milk is one of the most valuable foods available to humans, because it is a source of easily digestible protein and calcium ions and an important source of vitamins B Indeks dolny 2₂ and BIndeks dolny 12₁₂.

It is usually recommended to consume 2–3 glasses of milk per day, and for athletes, approximately 1 litre per day. Of course, you can replace milk with milk products. For example, considering the protein content, 2 glasses of milk can be replaced with two glasses of natural yoghurt or 100 g of curd cheese or 150 g of cottage cheese. Due to the source of protein and its assimilation, milk products, including beverages and curd cheese, are more recommended.

Task 1

Before you watch the movie „Study of cola beverage ingredients”, formulate a research question and a hypothesis.

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Wykonaj ćwiczenie zgodnie z poleceniem.

Wykonaj ćwiczenie zgodnie z poleceniem.

Analysis of the experiment: "Study of cola beverage ingredients"

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Research question

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Hypothesis

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Do kolby płaskodennej należy wlać 20 cm3 coli i dodać nieco węgla aktywnego. Zawartość kolby energicznie wytrząsać i odstawić na 10 min. Badaniu poddajmy odfiltrowany, klarowny roztwór. Kilka cm3 przesączu wlewamy do zlewki i mierzymy pH pehametrem. Określamy odczyn roztworu. 5 cm3 przesączu wlewamy do probówki, dodajemy kilka kropel stężonego kwasu azotowego pięć. Roztwór przelewamy do parowniczki i ogrzewamy tak długo, aż ulotnią się tlenki azotu. Po ostudzeniu roztwór przelewamy do probówki i dodajemy kroplami roztwór molibdenianu amonu. Pojawienie się żółtego osadu świadczy o obecności kwasu fosforowego pięć w roztworze. 5 cm3 przesączu wlewamy do probówki, dodajemy tyle roztworu wodorotlenku sodu, aż roztwór przybierze odczyn zasadowy (sprawdzić papierkiem uniwersalnym). Do tak przygotowanego roztworu dodajemy 2-3 krople roztworu siarczanu sześć miedzi dwa i lekko ogrzewamy płomieniem palnika.

Do kolby płaskodennej należy wlać 20 cm3 coli i dodać nieco węgla aktywnego. Zawartość kolby energicznie wytrząsać i odstawić na 10 min. Badaniu poddajmy odfiltrowany, klarowny roztwór. Kilka cm3 przesączu wlewamy do zlewki i mierzymy pH pehametrem. Określamy odczyn roztworu. 5 cm3 przesączu wlewamy do probówki, dodajemy kilka kropel stężonego kwasu azotowego pięć. Roztwór przelewamy do parowniczki i ogrzewamy tak długo, aż ulotnią się tlenki azotu. Po ostudzeniu roztwór przelewamy do probówki i dodajemy kroplami roztwór molibdenianu amonu. Pojawienie się żółtego osadu świadczy o obecności kwasu fosforowego pięć w roztworze. 5 cm3 przesączu wlewamy do probówki, dodajemy tyle roztworu wodorotlenku sodu, aż roztwór przybierze odczyn zasadowy (sprawdzić papierkiem uniwersalnym). Do tak przygotowanego roztworu dodajemy 2-3 krople roztworu siarczanu sześć miedzi dwa i lekko ogrzewamy płomieniem palnika.

Film dostępny na portalu epodreczniki.pl

Do kolby płaskodennej należy wlać 20 cm3 coli i dodać nieco węgla aktywnego. Zawartość kolby energicznie wytrząsać i odstawić na 10 min. Badaniu poddajmy odfiltrowany, klarowny roztwór. Kilka cm3 przesączu wlewamy do zlewki i mierzymy pH pehametrem. Określamy odczyn roztworu. 5 cm3 przesączu wlewamy do probówki, dodajemy kilka kropel stężonego kwasu azotowego pięć. Roztwór przelewamy do parowniczki i ogrzewamy tak długo, aż ulotnią się tlenki azotu. Po ostudzeniu roztwór przelewamy do probówki i dodajemy kroplami roztwór molibdenianu amonu. Pojawienie się żółtego osadu świadczy o obecności kwasu fosforowego pięć w roztworze. 5 cm3 przesączu wlewamy do probówki, dodajemy tyle roztworu wodorotlenku sodu, aż roztwór przybierze odczyn zasadowy (sprawdzić papierkiem uniwersalnym). Do tak przygotowanego roztworu dodajemy 2-3 krople roztworu siarczanu sześć miedzi dwa i lekko ogrzewamy płomieniem palnika.

Summary

• Drinks are an essential ingredient in our daily diet. In addition to satisfying the thirst by providing water and mineral salts dissolved in it, these can be the source of other substances that affect our body.

• The active ingredient of coffee and tea is the same substance with stimulating properties – caffeine. Caffeine is also included in cola drinks and energy drinks.

• Juices contain the same (beneficial to our health) ingredients as fruits and vegetables. These provide antioxidants and enrich the diet with essential nutrients such as vitamins, minerals and micro- and macronutrients.

• Milk is an exceptional drink because it provides practically all necessary nutrients (water, proteins, fats, carbohydrates, mineral salts and vitamins).

Keywords

Flavonoids, caffeine, theanine, theine, mineral waters, energizer, isotonic drink

Glossary