PROJECT 1: SUITABLE AND QUALITY FOOD

1. The purpose of the project is to introduce early-school children to the concept of "suitable" and "quality" of food. It will include tests - scientific experiments for children that are applicable to the Social Responsibility Applied Sciences section of Interests  activities. Prepared by the BULGARIAN and Spanish CHILDREN under the guidance of our teachers.
2. The children will fill up separately TABLES with the results of the experiments for selected by them country-specific foods and with SKYPEwill hold a SCIENTIFIC discussion by discussing and drawing together a small book "HOW TO KNOW THE QUALITY FOOD --- WHY WE HAVE TO KNOW ABOUT QUALITY Of food and WHY we can be useful in housekeeping and protecting our  health and the health of our loved ones. Let's be help  for Mother and Father,   for Grandma and Grandpa. "  In both languages.
3. The childern will realize the following experemients and activities with two very imporant foods such as eggs and legumes: 1º. Legumes in the kitchen (elaboration of a key dichotomous with the pulses that we can find in the supermarkets of your city). 2º. How to differentiate leguminous plant  from other plants (recognition of leguminous trees from parks and gardens in your city) 3º. Legumes in the supermarket (types of legumes and their homemade uses). 4º. The density of pulses (density experiments with pulses). 5. The Papiloneacea flower (learned flower structure with a leguminous flower model made with EVA Rubber). 6º. Legumes and art (seed and pictures).  7º. The eggs that change color. 8º. The jumping egg. 9º . Edible colors eggs. 10º. The radioactive egg. 11º. Differentiate between raw and boiled eggs. 12º. Fry an egg without heat. 13º. The egg of Columbus .14º. The egg that floats. 15º. The  egg Tangram.16º. The egg and the school garden.

4. The children themselves will draw and describe the experimenters by explaining them at their age and formulating the PRINCIPLES of the Healthy Eating they will share with their classmates from neighboring classes and / or schools.

-      Scientific experiments are based on basic physical and chemical laws which  can explain and demonstrate clearly cause and effect relationships and why things happen around us. Some of them are related to healthy eating and how to check the suitable and quality of the foods and types of water that we buying and consuming in our daily lives.

Experiments are planned and conducted in the classroomwhere we entertain together and learn new things. Suggested experiments do not require special conditions and training and  they are fast, easy and funy. It is planned that my colleague from Spain will hold a joint lesson at the our town  Kyustendil, where  will meet with the town, while we will be able to exchange practices related to CHEMISTRY and environmental protection.

We will create a glossary of the words and phrasesthatwe will use in Bulgariaand a glossary of words and phrases that will be used in Spain.

We will write TOGETHER SONG for Health and Healthy Eating

Sample topics            

What water do we drink and what do we know about it?

Types of water and its qualities.

What does a healthy diet mean?

Which foods are included in a healthy diet?

This,  thinks to which not only the stomach but also the body and our spirit feel good.

What is good food?

The one that is made from natural quality and fresh products in a way that preserves their maximum beneficial properties and with a taste that deserves the calories absorbed.

Here are some easy   ways  to check the quality and suitable of food products such as milk, yoghurt and eggs as well as the quality of the water we drink.

Experiments.

1. How to check if the yogurt is real? Is there а  starch in it or not?

1. In a small cup put a spoonful of yogurt.

2.Put  2-3 drops of iodine and wait a few minutes.

If milk is starch, the color will be blue and purple if there will remain brown. 

Clutter. Easy. Interesting.

It is important to know what we eat !!!

The starch is not harmful to health, but it is not desirable to have it in yogurt.

2. Multicolored milk

What you need:

milk, food coloring, liquid detergent, cotton buds, dish.

experiment:

Pour a little milk on the plate. Add a few drops of food coloring. Take a cotton swab and dip one end into the cleaner. Then put this very near the center of the plate. Milk begins to form a variety of colored forms.

How it works: the detergent react to the touch of fatty molecules in the milk and began to move.

 I.e. if you use low-fat milk  the experiment will not work. 

3. How to know if eggs are fresh?

Fresh or not are eggs?

Surely many times you've asked yourself this question. Eggs are one of the most  beneficial and healthy food sources  but if they are not fresh can be quite dangerous to human health.

How do we know whether they are fresh or not?.

All you need for this  experience a bowl full of water. Put eggs inside and monitor whether .

 Tthey will stay at the bottom or swim.

Here are a few examples:

1. Fresh Eggs

The eggs will fall to the bottom of the bowl and will remain so lying on its side.

2. One week

Eggs on a week will remain on the bottom of the bowl but the lower (wider) part will be raised slightly.

3. Two or three weeks

Eggs on  three weeks would still be retained on the bottom of balancing its upper part and the lower part of it will be raised up. Such eggs should be eaten as soon as possible because soon become inedible.

 4.Rotten

Eggs which is already spoiled or unfit for consumption will resurface and will remain there.

Such eggs should not be eaten, they are no longer harmful to health.

Be careful what you eat !!!

Here are some scientific experiments that explain some physical and chemical laws

5. How do we get a whole egg into a bottle?

What do you need:

1. A glass bottle or flask with a wide neck.

2. Peeled hard - boiled egg.

3. Matches.

4. Piece of paper.

5. Compulsory parental supervision.

Choose a small egg. Cook it for a longer time than usual. It must be really peeled hard - boiled egg . Coat the neck of the bottle with oil.

After burning match the pressure in the stoppered bottle becomes lower than the air pressure outside and inside the egg slides.

6. Invisible letter

1.With cotton swab in an alkaline solution such as aqueous  baking soda.

2.Write something on white filter paper.

Writing still not visible since the solution of baking soda is colorless. If you apply a solution of turmeric on paper white paper turns yellow and alkaline surface of  the writing - brown.

What explains this phenomenon?

Pigment known as curcumin becomes brown in alkaline medium thus playing the role of an indicator.

7. Hidden message

Write something with acid of lemon.

Waiting to dry. Heat the writing  on the flame of a burning candle.The writing occurs from the hea  and so we can read the hidden  message.

8. Fruit cell

1.Let’s doing  galvanic element of small pieces of metal and fruits, in which chemical reactions produce electricity.

2. Place two different metals (eg. Copper and zinc)  in juicy, acidic fruit or vegetable and mounted LED    lamp lights up immediately.

How is that possible?

Since the processes of separation and absorption of electrons is carried out in various fields, is carried out electron transfer between the two parts. Metals and surrounding solution (in this case fruit juice) play the role of electrodes and electrolyte whose electric potentials vary. Two electrodes connected by solution form galvanic element, the difference between the potentials of the two electrodes is electromotive force. The conversion of chemical energy  into electrical energy due to the oxidation and  reduction processes  in the electrodes.    

9.  The Ph of the water

Ph is a measure of acidity or alkalinity of the water.

The scale of Ph is from 0 to 14. 

The alkaline Ph is greater than 7.

Neutral water has a Ph 7 and the acidic water has a Ph of less than 7.        

      

What water you drink?

Spring, mineral, filtered - make a difference?

Two simple molecules - hydrogen and oxygen are connected to create one water molecule, the most massive and the most important substance on Earth and the human body. However, hydrogen and oxygen atoms are not only in water, because it is a universal solvent and it is always present, and other elements, which means that 100% pure water (unless it is artificially purified) does not exist. The composition of the Earth's water is different for each geographical point, and hence the composition of the water in our body.     

      In the body of every adult has at least 60% water, but it was much more in the beginning. In the 32nd week of pregnancy the fetus is 80% water and is surrounded by amniotic fluid resembling ocean water.

The germ permanently absorb about 250 milliliters per kilogram weight of the water, using it for food (equivalent is 18 liters of water per day for an adult). Without this water the embryo would not have received the necessary valuable substances to develop, and his digestive system would not function properly.

That is why water is the most important element in the human body, the main component in all fluids - blood, lymph, tears, digestive juices, urine and sweat. Water is involved in almost all the functions of the human body - circulation, digestion, assimilation, elimination and much more.                            

              "The best" water?

But what water is the best drink is a complex issue that has no definite answer. However, here are some things you should know about our drinking water to do the better choice for themselves.

First, always conformed to their personal sense of smell and taste - this is the easiest way to our body a signal that something is good for us.

If water has a bad taste or smell - do not drink.

Unfortunately, some toxins and pollutants  in water taste and odor free ...

What must be careful where to find it?    

            Tap water

The water that flows from our taps at home comes from groundwater or from land-based tanks such as rivers, lakes and reservoirs. To reach us, this water passes through treatment plants that filter it and add chemicals for further purification.

Each state has a regulatory body which monitors drinking water should not exceed certain levels of contamination with microorganisms (bacteria, viruses and parasites), disinfectant (chlorine), inorganic chemicals (heavy metals, asbestos, nitrates and nitrites) and organic chemicals (pesticides, plastics, solvents). In other words, it is accepted as normal drinking water contain these contaminants, but within certain limits so that they do not harm the human body.

Despite purification and adding purifying chemicals but in recent years more and more frequently observed serious pollution of drinking water, mainly pesticides and fertilizers of modern agriculture, which seep into underground layers of soil  and hence in ground tanks themselves pipes and others.  

The most common contaminants in drinking water are:

Lead - mostly from corrosion of old pipes water from solder in water pipes and the content of lead in brass valves. Higher risk of contamination with lead are people living in old buildings with old pipes, as well as families with small children because children toksikirat easier.

Nitrates - especially in rural areas, wherein the monitor and higher levels of toxic pesticides and herbicides. Under particular risk for toxicity nitrate babies, pregnant women and people with serious illnesses because nitrates are converted to nitrites by the bacteria in our digestive system and these nitrates can alter the hemoglobin molecule, turning it into methemoglobin, which can not carry oxygen. Other possible contaminants are mercury, arsenic, radon and others.

As a general conclusion, I would recommend   avoiding tap water as drinking water or purified further.

Water from a well

This water comes from underground sources and contents of minerals and toxins can vary dramatically from low mineral content to high mineral from low to high toxic. To use this water, not necessarily her make analyzes for bacteria, mineral content and organic chemical contaminants. If everything is the norm - drink freely and wear analysis once a year to stay calm.

Spring water

This water comes from underground springs and ground and normally sells bottled. This means that it is disinfected (possibly with chlorine) and untreated.

Its mineral content depends on the geographical location of the spring, but is generally assumed that groundwater are higher mineral content (recommended), and ground with a very low one.

Another factor that can affect the quality is whether bottled on site (recommended) or transported and bottled elsewhere. And the last thing to keep track of when choosing a spring water is pH-it her. It is desirable that it be written out of the bottle and a base above 7.0.

In summary, the spring water is a very good option for drinking it is advisable comes from an underground source  to be bottled on site and have a pH of 7.0 above.

Mineral water

All mineral waters are, that contain a certain amount of minerals. To be bottled and sold, however, as such, must have a certain minimum content of minerals. General here apply the same rules as spring water.

Filtered water

Filtering or purifying water constitutes remove unnecessary substances which could be chemicals, metals, bacteria and minerals even thereof.

By law in order for a system to be called "cleansing", it must remove more than 99.75% of bacteria in the water

The most popular methods for purifying water are:                               

Activated carbon, or charcoal filter. These filters mechanically or biomagnetic (ion) purify the water, removing the bad taste and smell coming from bacteria, parasites, viruses, chlorine, organic chemicals and heavy metals (lead, mercury, etc.), But not entirely eliminated lighter and small items.

In practice, these filters only remove particles and organisms larger than 0.4 microns, or as the size of the filter itself. There are doubts, however, that the detainees bacteria may be re-treated water or to multiply in the filter itself, especially if we try to purify hot water. To further facilitate the killing of harmful bacteria, some manufacturers add silver to the filter, but for the moment is still not 100% proven that it is as effective as claimed.  

 In conclusion, the carbon filters are fairly good option for  water, but must be replaced regularly, have added silver to the filter and should not be used for treatment of hot water.

 Solid carbon block, or filter with solid hydrogen unit. In these filters are not standing problem of additional contamination or retention of microorganisms because the bloc has no oxygen and virtually bacteria can not exist. Studies show that these filters also retain more chemicals, organic pollutants, radon and asbestos than those with activated charcoal. An important factor in these filters is their micron rating, as best considered with such a filter is not greater than 1 micron    

      Reverse osmosis, or purification by reverse osmosis. Globally, it is considered one of the best waste disposal systems that are installed directly on the tap or at the entrance to the pipes in the house. The system operates as a voltage below the water passes through special membranes with microporous holes to the size of water molecule. These pores allow water molecules to pass but keep all other inorganic and organic materials. These filters purify elements with size 0.009 microns, that is at times better than all the filters listed so far. RO systems typically have several different filtering mechanisms in the process removes the water almost everything, even valuable minerals.

In conclusion, this system is great for water, especially if you put the whole house and even filtered water with which to bathe, wash, etc., but because of its reduced mineral content is better not to count only it for drinking water.                                                              

Distilled water

The process of distillation is a water evaporation in a chamber and holding it as a liquid in the other chamber, in this process the water removes all minerals organisms and chemicals. All that remained were the chemicals whose boiling point exceeds that of water, so before distillation water is passed through a filter for purification.

Due to the removal of water of all minerals tyane recommended for permanent use as drinking water.

As final conclusions, it is recommended drinking a combination of water - spring, mineral and purified.

All these attempts were  made in times of Applied Science in Classes interest. 

They form at younger students love and knowledge of science from the earliest school age.

And why not maybe formed in the future scientists?

  

The project includes scientific experiments that are tailored to the age group of the participants and were conducted in Activities classes  and Interest of Section Applied Science.

Scientific experiments are simple and clever way to familiarize your child with some basic physical and chemical laws that can explain the laws of nature and to show clearly why things are happening around. Experiments performed our time in classroom where together  having fun and learning new things. The proposed experiments do not require special conditions and training and are quick, easy and funny.