Physical properties of chocolate. Physics in Chocolate Completed by: Boglaev Nikolay Supervisor: Plutalova E.V.

Municipal educational institution

"Secondary school number 8"

Physics in chocolate

Completed

Supervisor

Physics teacher

Introduction ……………………………………………………. …………………… ..… ..3

1. All about chocolate.

1.1. The history of chocolate …………………………………………………… ..... 4

1.2. Cocoa products …………………………………………………………… .7

1.3. Chocolate production technology ……… ... ………………………… .... 9

1.4. About the benefits of chocolate …………………………………………………… ... 12

1.5. Chocolate recipes ……………………………………… .13

1.6. Criteria for assessing the quality of chocolate …………………………………… 14

2. Study of the physical properties of chocolate.

2.1. Criteria for selecting chocolate for the experiment ………………………… .16

2.2. Study of the physical properties of chocolate …………………………….… .16

2.3. Experiment results …………………………………………… ........ 21

Conclusion ………………………………………………………………………… ..22

Literature …………………………………………………… ... ………………… ...… 25

Appendices ……………………………………………………………………….… 26

Introduction

Chocolate is a very popular delicacy all over the world, which neither adults nor children refuse.

We are accustomed to the fact that girls are considered sweet tooth. But I also like sweets, especially chocolate. They say that if a man loves sweets, then he is kind. According to my friends, I am a kind person, hence the saying is right. And I decided to find out how useful chocolate is for us, whether all types of chocolate are the same in composition and whether they are different in properties.

There is a lot of chocolate now. It is different in taste, color, composition. Chocolate is produced by different companies. Each manufacturer has its own method of making chocolate, its own production technology. Each company tries to make such products so that they are not only attractive, but also have their own special shapes, fillings and taste.

I wonder what is the story behind this product? How is it made? Is chocolate really good for you? If so, how is it useful? Here are some of the questions I have posed and tried to answer.

I wanted to know a little more about chocolate than the average consumer knows, therefore, the consumer, to consider some of its properties from a physical point of view.

The purpose work is - to study some of the physical properties of chocolate and its effect on humans.

To achieve this goal, it is necessary to solve the following tasks:

1. Study literary and electronic sources of information.

2. To systematize and summarize the found material.

3. Conduct a study of the individual physical properties of chocolate.

1. All about chocolate

1.1. The history of chocolate

The history of chocolate began a long time ago. About 1500 BC, the Olmec civilization arose in the lowlands on the coast of the Gulf of Mexico in America. Very little remains of their culture, but some linguists believe that the word "cocoa" first sounded like "kakawa" around 1000 BC, during the heyday of the Olmec civilization.

The Maya attached great importance to cocoa. Chocolate was drunk during rituals as a sacred drink. In the pantheon of the Mayan gods, there was a cocoa god. The Maya set up the first known cocoa plantations. They had well-developed methods for preparing various types of chocolate drinks using all sorts of additives and components - from cloves to pepper. The Indians did not know the sugar at all.

Cocoa beans were a symbol of wealth and power. Only the elite could afford a drink made from chocolate beans. The chocolate beans themselves were used instead of money. A slave could be purchased for 100 beans.

"Chocolate tree"

In botany, the "chocolate tree" is called "Theobroma cocoa", which means "food of the gods." The Aztecs considered him a "tree of paradise" and worshiped him as a divine creation. This tree grows only in warm and humid climates, in the heart of rainforests - mainly in the Americas, Australia and some islands in Asia. Plant height can reach 10-15 meters. A photo of a chocolate tree is presented in Appendix No. 3. The harvest is taken twice a year - the main harvest in October-February and the intermediate one in May-June. Each fruit contains 20 to 50 seeds - cocoa beans. They can be round, flat, convex and have a grayish, bluish or brown tint. A healthy tree can produce up to 2 kilograms of beans per year. Freshly harvested cocoa beans have a bitter-tart taste and pale color; as such, they are unsuitable for use in the manufacture of chocolate. Fresh cocoa beans contain approximately 30% water and 30% cocoa butter.

The Aztecs played an important role in the spread of cocoa in the New World. Aztec legend says that cacao seeds came to us from Paradise and that wisdom and strength emanate from the fruit of the cacao tree.

The Maya called the chocolate drink "xocolatl" ("xokolatl"). This name is made up of a combination of two Indian words: "choco" or "xocol" - "foam" and "atl" - "water". This may have been because early chocolate was only known as a beverage.

Cocoa beans also served as a kind of money among the Aztecs. The amount of cocoa beans that was stored in the barns of the palaces of the Indian leaders is striking. One of these palaces consumed 486 bags of cocoa per year, each bag contained about 24,000 grains.

The first European to taste chocolate was Christopher Columbus. It happened in 1502, when the inhabitants of the island of Guyana wholeheartedly treated their dear guest with a drink made from cocoa beans. They say that Columbus delivered the mysterious grains to King Ferdinand from his fourth expedition to the New World, but no one paid attention to them - the navigator brought too many other treasures.

Twenty years later, Hernan Cortez, the conqueror of Mexico, also tried Xocolatl. When Cortez first entered the land of the Aztecs in 1519, he was mistaken for a god ... In a golden bowl in front of him was smoking a strange bitter drink made from boiled cocoa beans with spices, pepper, honey, whipped to a foam.

This was the first chocolate to which the Spanish conquistadors gradually got used to, replacing pepper in this drink with vanilla and adding nutmeg and sugar to give a stronger aroma.

In 1526, on his way to report to the Spanish king, who had heard rumors of his cruelty, Cortez took with him a box of selected cocoa beans. This time the chocolate was lucky: the exotic aromatic drink was favorably received at the Madrid court.

Soon chocolate became an obligatory morning drink of the Spanish aristocrats, especially the ladies of the court, replacing the tea and coffee that were quite widespread by that time. The cost of the new drink was so high that one Spanish historian even wrote: "Only the rich and noble could afford to drink chocolate, since he literally drank money."

Over the next 100 years, "Xocolatl" from Spain penetrated into Europe, eclipsing other overseas goods in terms of price and popularity. The German Emperor Charles V, realizing the commercial importance of cocoa, demands a monopoly on this product. However, already at the beginning of the 17th century, smugglers began to actively saturate the Dutch markets with chocolate, and in 1606, through Flanders and the Netherlands, cocoa reached the borders of Italy. Nine years later, the daughter of Philip III brought the first box of cocoa to Paris.

1650 The British begin to drink chocolate. In 1657, the first "Chocolate House" was opened in London - the prototype of the future "Chocolate Girls". The drink becomes a part of the culture, the time is calculated according to it: "Come to chocolate" means: "We are waiting for you by eight o'clock in the evening."

In 1674, rolls and cakes were made on the basis of chocolate. This year is considered the date of the emergence of "edible" chocolate, which could not only drink but also eat.

1825 year. The British Navy purchases more cocoa than the rest of Europe. The chocolate drink is as if created for the sailors on duty: nutritious, non-alcoholic. Among the sailors, the strong cold northwest was called "stormy chocolate".

In the 19th century, the first chocolate bars appeared, and Jacques Nehaus invented the first praline-filled candy.

This is such a long historical path that cocoa beans have come to our modern hard chocolate.

1.2. Cocoa products

If you look in the dictionary, then there are two concepts of the word "chocolate":

chocolate (German Schokolade):

1) A confectionery product obtained by processing cocoa beans with sugar. Chocolate has a delicate taste and aroma, high calorie content, and the ability to be stored for years without changing its properties. Chocolate is made with or without filling - in the form of natural chocolate and chocolate with additives, which includes milk, coffee, nuts, fruits, etc. The energy value of chocolate is up to 2.33 MJ / 100 g (557 kcal / 100 g ). The average composition of chocolate produced by the confectionery industry: sugar 50-55%, cocoa butter 35-37%, the rest is the fat-free mass of cocoa beans. Additives are introduced by reducing the proportion of the cocoa beans. Chocolate reinforces and quickly restores human strength, therefore it is convenient for expeditions, hikes, etc. It also contains about 40 volatile compounds that determine an attractive, incomparable smell. By the way, physiologists have established that this aroma has a beneficial effect on the psyche: it relieves irritation, pacifies, even restores peace of mind.

2) A drink made from chocolate powder.

Chocolate is a convenient base for flavoring and flavoring various dessert dishes (jelly, blancmange, jelly, mousses, soufflés, creams). It is used in cakes; cakes as an additive to the dough, in impregnations for it and creams. Decorate with chocolate plates and confectionery shapes.

Cocoa powder

Semi-finished cocoa - production powder is obtained by grinding particles of defatted mass of grated cocoa (cake). It should be light brown to dark brown in color, have a characteristic cocoa flavor and aroma, and have a powdery structure. The moisture content of the powder should be no more than 7.5%, the fat content in it should be no less than 14%. The presence of ferro-impurities per 1 kg of the product is no more than 3 mg. Cocoa powder is widely used for making chocolate creams, chocolate fondant, and also in dough. Cocoa powder should be stored at 18 ° C and a relative humidity of no more than 75%. The shelf life is guaranteed - 6 months from the date of production.

Chocolate glaze (couverture)

A semi-finished product is a carefully ground mass of cocoa liquor with powdered sugar and cocoa butter without or with the addition of various flavoring and aromatic substances. The moisture content should be no more than 1.3-1.5%, heat and sucrose - in accordance with the recipe; the degree of grinding (according to Reutov) is not less than 90%, the taste and aroma are typical for this type of glaze, the color is from light brown to dark brown, in the frozen glaze, graying on the outside and inside is allowed. The consistency of the glaze is solid at ° C, and fluid at 40 ° C. The glaze is packaged in polymer films, corrugated cardboard. Storage is carried out at 18 ° C and a relative humidity of no more than 75%. Shelf life is 6 months.

Chocolate is a processed product of cocoa beans with sugar, with various additives or without additives. The chocolate must be hard. Figured and patterned chocolate can be of any shape, size and weight. It should be dull in the fracture, have a smooth surface without a grayish coating. Moisture content of chocolate (without additives) - no more than 1.2%. It should be stored at 18 ° C and a relative humidity of no more than 75%. Shelf life up to 6 months.

Roasted buttery kernels, finely ground with sugar, cocoa butter and cocoa liquor, are called pralines. It should have a light brown color, nutty taste and odor, no spoiled or rancid aftertastes, and no other unpleasant aftertaste or odor. After production at the factory, praline is a loose rolled mass, which is usually supplied to other enterprises in the form of a compressed monolith. Before use, pralines are heated to a greasy or liquid state. In the latter case, it is filtered through a sieve with meshes of 2 mm. Pralines are used as fillings in waffles, cakes and other products. The finished mass is stored in clean wooden barrels in a dry warehouse at 8-120C for no more than 3 months.

Cacao butter

Cocoa butter is a semi-finished product of chocolate production, obtained by pressing grated cocoa. At a temperature of 16-180C, the consistency of the oil should be hard, brittle, the temperature of complete melting is 32-35 ° C; at 40 ° C, the butter should be transparent, with a small amount of grated cocoa particles; color from light yellow to brown; taste and aroma - characteristic of cocoa beans. Store cocoa butter in a dark place in a well-sealed container at temperatures up to 18 ° C and relative humidity up to 75%. Shelf life up to 6 months. Cocoa butter is used for making chocolate glaze and praline.

1.3. Chocolate production technology

A modern factory for the production of chocolate is an automated line with electronic control, closed from any external influences, the technical equipment of which allows you to maintain the specified technological parameters at different stages of production, which guarantees the production of high-quality chocolate products with a long shelf life without the use of stabilizers and preservatives.

Its work is completely controlled by a computer: the "virtual brain", depending on the type of product being produced, chooses one of the programs stored in its memory, and he himself monitors all processes, monitors the maintenance of the external temperature regime and the speed of operations. If necessary, he checks his work and makes the necessary adjustments.

The main technological stages on the production line are the preparation of the main components (according to the recipe), their mixing, grinding, tempering the chocolate, preparing the filling, molding the chocolate, dosing the fillings and additional ingredients (nuts, puffed rice), wrapping and packaging. At the factory, much attention is paid to the selection of raw materials, their analysis - after all, this is a guarantee of the quality of chocolate.

Manufacturing process and methods of making chocolate

The production process begins with the preparation of chocolate mass and filling in accordance with a given recipe, which are then fed to the production line. To make chocolate, cocoa beans are sorted, cleaned of impurities and fried at a temperature of oC. Then the beans are crushed into grains and separated from the shell on crushing and sorting machines. The nibs are ground in roller or millstone mills, and converted into a liquid mass of grated cocoa. Pure cocoa butter is squeezed out of a part of the cocoa liquor on hydraulic presses. The chocolate mass is prepared by mixing cocoa liquor, cocoa butter, sugar (usually powdered sugar) and the necessary flavoring and aromatic substances. The mass is ground in roller mills to a solid particle size of no more than 15-20 microns, mixed again with the addition of cocoa butter and fed to the formation of ordinary chocolate and to the icing of sweets. To obtain dessert chocolate, the mass is additionally processed in separate machines, the so-called conches, at a temperature of about 70C (on average, 3 days); this achieves complete uniformity in the distribution of solid particles, volatile acids are removed, and diffusion of the aromatic substance occurs. Then, on a temperature machine, the temperature of the mass is brought to 30-32 ° C. To form slab chocolate, the mass is poured into metal molds, which pass along vibrating tables and are cooled in a refrigerating chamber at a temperature of 5-10 ° C.

To form chocolate with filling, the walls of the mold cells are first covered with a layer of chocolate, and after cooling, the filling is poured and then a layer of chocolate forming the bottom of the product. The most important process in the production of chocolate is tempering - gradual and controlled cooling at a specified temperature.

The design of the tempering machines and the principle of gradual cooling of the chocolate based on them allow the maximum amount of Beta crystals to be distributed throughout the chocolate mass (the optimal structure of this crystal, which allows to obtain chocolate with a long shelf life). Therefore, the finished chocolate not only acquires an aesthetically pleasing appearance, but also becomes more resistant to the unwanted effects of elevated temperatures.

The final phase of the complex chocolate production process is molding - where the dies, advancing with alternating "cold" and "hot" sections, are filled with molding machines with chocolate, fillings and various ingredients (puffed rice, nuts) are dosed into them. Then the dies are turned over (well-tempered chocolate is easily released from the molds), and the finished product goes to the wrapper.

Modern wrapping machines have a high performance, which allows you to wrap 6 items per second. Next, the finished, wrapped products are packed into boxes.

Unfilled chocolate is produced in the form of bars weighing from 4 to 100 g and various shapes, chocolate with filling in the form of loaves weighing from 50 to 100 g. All chocolate products are stored at a temperature not exceeding 15 ° C in a room where there are no side odors. The shelf life for chocolate without additives is up to 6 months, for chocolate with additives and filling - up to 3 months.

1.4. The benefits of chocolate

How to test chocolate "for usefulness"? 25-30% of the content of cocoa beans in the bar indicates a rather low quality of this chocolate, 35-40% characterizes chocolate of average quality, 40-45% is present in the product is quite good, but the content of cocoa beans from 45 to 60% speaks for itself for yourself - before you is an excellent chocolate bar that will do you good. There is still debate about whether chocolate is healthy, or whether it only adds extra pounds to us. Studies by Californian scientists have shown that cocoa contains substances that protect the arteries and, therefore, are beneficial for the cardiovascular system. They are called "phenols". These substances prevent the oxidation of cholesterol and prevent the deposition of fat on the walls of blood vessels. Half a bar of milk chocolate contains the daily dose of phenols - as much in a glass of red wine.

There is an argument for white chocolate. This is best for children who are allergic to cocoa. White chocolate consists of harmless foods - milk powder and cocoa butter. Thanks to the content of the latter, this dessert can not only be eaten, but also treated with it. Cocoa - oil is useful for sore throats. So melt the white chocolate in the boiled milk and the medicine is ready. Children will drink this with pleasure.

Since the moisture content of chocolate is low, up to 1%, it does not undergo microbiological deterioration and can be stored for a long time. For this reason, chocolate is often taken on long expeditions and hikes, as it reinforces and quickly restores human strength.

It also contains about 40 volatile compounds that determine an attractive, incomparable smell. By the way, physiologists have established that this aroma has a beneficial effect on the psyche: it relieves irritation, pacifies, even restores peace of mind. Eat chocolate and be calm.

1.5. Chocolate recipes

You know what, the favorite dessert of many comes from three
main components: cocoa powder, cocoa butter or other fats, sugar. The rest is, so to speak, "applied" in nature and depends on the recipe of a particular type of chocolate. Nuts, powdered milk or cream, flavors, various fillings are added to it. I propose to get acquainted with several recipes for making chocolate.

French chocolate

For four cups of water, add 100 grams of dark chocolate, broken into pieces. First, put the chocolate in a cup of warm water, then, when it melts a little, put it on a small fire until it is completely dissolved. When it turns into a homogeneous mass, add three more cups of water, bring to a boil, stirring constantly, leave for 10 minutes on very low heat. Remove from heat, whisk and serve hot. Sugar is added to taste. If you are making coffee with milk, then first dissolve the chocolate in boiling water, then add warm milk. Once everything is smooth, bring to a boil, whisk and serve hot.

Viennese chocolate

This is a completely different chocolate both in taste and in the method of preparation. First, you cook it in the French manner, add two or three yolks (very fresh), mix the mass thoroughly, put on a very low heat and wait until the mass thickens, but do not bring it to a boil. Then pour the hot mass into cups and add one tablespoon of "cream - fresh" to each cup (this is a dairy product similar to our thick homemade sour cream, you can replace it with it). Everyone adds cream - fresh to taste.

Chocolate elixir

1/2 l milk, 2 egg yolks, 100 g sugar, 50 g chocolate, vanillin, crushed ice.

Pour hot milk into the yolks, whipped well with sugar, in a thin stream. Cook the resulting mixture over low heat, stirring without fail, for a few more minutes. After removing from heat, add the grated chocolate and vanillin. Cool the finished cream, mix with crushed ice and serve immediately.

Chocolate sorbet

Pour 600 ml of water into a saucepan with a thick bottom, add 250 grams of vanilla sugar. Put everything on low heat. While stirring, bring to a boil. Cool the resulting mass. Add 150 grams of cocoa powder to the resulting mass and heat while stirring over low heat. You should get a silky mass, which must be wiped through a sieve, put in bowls, cooled in the freezer, stirring every half hour 2-3 times.

Sweet sausage

Melt 1 packet of margarine, add 200 grams of sugar. Remove from heat and cool, then add 1 egg, 3 tablespoons of cocoa and 2 packs of finely crushed cookies. You can have a nut, raisins to taste. Mix everything until smooth, form a sausage and put in the refrigerator.

1.6. Criteria for evaluating the quality of chocolate

Good chocolate has a glossy surface without stains. If it is "gray-haired" - it means that either the production technology was violated, or it was stored incorrectly. An increase in dryness and hardness is an indicator of spoiled food. The smell should be in harmony with the aroma of cocoa alone. With the last parameter, everything is clear: chocolate is either tasty or none at all. Good chocolate melts in your mouth and leaves a smooth, smooth feel.

By the way, this "phenomenon", as it turned out, has a very simple explanation, which lies in the physical properties of one component of this dessert. The recipe of natural chocolate is not much different from different manufacturers. And you can stand out here only by quality. The Swiss, who are considered the greatest connoisseurs of chocolate, rate it according to several parameters: appearance, smell, break and taste. Chocolate is made with the addition of cocoa butter or other fats. The first product is expensive, so some manufacturers use cheaper raw materials instead: it is good if the equivalents of cocoa butter are worse - its substitutes, which are much inferior in quality.

The base of the chocolate bar, which makes it hold its shape, is cocoa butter, which is white in color. Add powdered milk and powdered sugar to it and get a white chocolate. Dark chocolate is also cocoa butter plus cocoa powder, which gives the bar its dark color.

Melting point of cocoa - oils 32 0С, that is, lower than the human body temperature, and substitutes - 380C and above. Therefore, chocolate with cocoa butter melts in the mouth, and with a substitute, it feels like a piece of bar stuck to the palate.

2. Experimental part.

2.1. Criteria for the selection of chocolate for the experiment.

In addition to cocoa powder, modern varieties of chocolate include sugar, cocoa butter, skim milk powder, glucose syrup, vanilla or vanillin, ethyl alcohol syrup, invert sugar, vegetable (nut) oils, nuts (hazel, hazelnuts, almonds), lecithin, pectin, natural or artificial flavors, preservatives (sodium benzoate), citric acid, lemon oil, orange oil, peppermint oil. These components help to diversify the flavors of both the chocolate itself and especially its fillings. Along with traditional varieties, salty, bitter, porous chocolate is also now produced.

I decided to experiment with chocolate without additives.

2.2. Study of the physical properties of chocolate

When choosing the physical properties of chocolate that could be studied, I proceeded from the equipment available in the physics classroom.

In order to compare the results obtained with any else already known, I repeated the experiments of Canadian researchers who determined the melting and hardening temperature of their chocolate.

In addition, I have determined the density of various types of chocolate.

1 experience

Determination of the density of chocolate

For my research, I initially decided to use only chocolate without additives, as nuts, raisins, puffed rice and other components can complicate the experiment procedure and affect the results. Thus, I decided to study white and dark chocolate, both regular and porous, and I also purchased a bar of milk and dark chocolate. I had to conduct experiments with 5 varieties of chocolate.

For the experiment, we used both Russian chocolate and imported chocolate from the well-known company "Nestle".

I only measured density for non-porous chocolates. To determine the mass of chocolate, I used a scale with a set of weights. Observing all the weighing rules, I received the following results.

	CHOCOLATE	MASS, G
	LACTIC
	"GOLDEN MARK"
	LUMP

I used a beaker to measure the volume of the selected piece of chocolate bar. Chocolate was dipped into a beaker of water. (he drowns in water). This fact led to the assumption that the density of chocolate exceeds the density of water. After the procedure for determining the volume, the following values ​​were obtained:

	CHOCOLATE	VOLUME, M3
	LACTIC
	"GOLDEN MARK"
	LUMP

The obtained values ​​were substituted into the formula for determining the density of a substance ρ = m / V and received the following values:

	CHOCOLATE	DENSITY, g / cm 3
	LACTIC
	"GOLDEN MARK"
	LUMP

After calculating the density, he proceeded to determine the melting and hardening points of various types of chocolate.

2 experience

Determination of the melting and hardening time of chocolate

Appliances and materials: grater, stove, electronic thermometer, stopwatch, aluminum glass, beaker and pouring vessel, airfryer.

	CHOCOLATE	CARBOHYDRATES	FATS	PROTEINS
	"Babaevsky"

First, I determined the density of the selected chocolates. Having done the procedure similar to the previous one.

I heated up the airfryer up to 180 ° C.
I put the pieces of chocolate on a saucer and put them in the airfryer.
The chocolate melted in the following sequence
Nestle - 3 min.
Milka - 4 min.
Babaevsky - 4.5 minutes

Conclusion: the more vegetable fats in chocolate, the faster it melts. In our case, it is “Nestle».

After melting the chocolate, I put it in the freezer.

At a temperature of -10 ° C, chocolate freezes in the following sequence

"Babaevsky" -1 min.

"Nestle" -1.5 minutes

Milka - 2 min.

Conclusion: the more animal fats in chocolate, the faster it freezes. In our case, it is "Babaevsky".

Experience number 3

Determination of the melting and solidification temperature of chocolate

I rubbed each kind of chocolate chip. The shavings of chocolate were poured into an aluminum glass and placed on a preheated plate. The chocolate chips were heated until they melted. After that, the stove was turned off, an electronic thermometer was placed in liquid chocolate, and for a certain period of time the thermometer readings were recorded at intervals of 30 seconds. Then they put the container in ice water until the glass with chocolate has cooled to a temperature of 17 ° C.

Then, again they began to smoothly heat the aluminum glass, in which there was already hard chocolate, and the temperature was recorded for a certain period of time.

Curing curvesand meltingchocolatepresented in graphs

Melting curve of chocolate "Zolotaya Marka" Curve of hardening of chocolate "Zolotaya Marka"

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Melting curve for lumpy chocolate Hardening curve for lumpy chocolate

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Analyzing the graphs, we can conclude that the temperature change both during heating and during cooling is not linear. The melting and solidification points of the studied types of chocolate are the same and equal to 330C, despite the fact that their density is slightly different.

2.3. Experiment Results

3 experiments were carried out, but their result was different. As a result of the first experiment, I was able to determine the density of different types of chocolate, as a result, the following values ​​were obtained:

	CHOCOLATE	DENSITY, g / cm 3
	LACTIC
	"GOLDEN MARK"
	LUMP

The density of different types of chocolate is different, it is determined by the composition, and since the types of chocolate are different in their composition, then its density is different.

In the second and third experiments, all the tasks that were initially set were fulfilled. Call "href =" / text / category / koll / "rel =" bookmark "> colleagues presented in the article, I got similar dependencies, and the melting and solidification temperatures Russian and Canadian chocolate coincided and equal 33 0С.

Conclusion

Analyzing the information about chocolate found in various sources, I tried to systematize it, resulting in a block diagram presented in Appendix # 1.

This diagram shows what the cocoa beans are, which are the basis for making chocolate, namely Asian, American, African, as they are called according to the place where the chocolate tree grows. All chocolate produced in the world is divided into five types:

· Ordinary, with or without additions;

· Dessert, with or without additions;

· With fillings;

· Diabetic.

In terms of quality, all produced chocolate is divided into noble and consumer ones. Also, in this diagram, I tried to reflect the structure of the production process for obtaining chocolate from cocoa beans, which consists of the following stages: preparation of cocoa beans - roasting, grinding, grinding, preparation of the chocolate mass, molding and cooling of the finished product.

During the experiment, I determined the density of the chocolate used. As can be seen from the data obtained, the density of different chocolates is different, which is explained by the different composition and percentage of cocoa powder. When determining the melting and solidification points, it was possible to obtain the data on which the graphs were plotted. According to the graphs, the melting and solidification temperature of chocolate was determined, which was 33 ° C.

Comparing the results obtained with the results of a study of similar parameters of chocolate by Canadian scientists, we can say that Russian chocolate, of high quality, is not inferior in characteristics to Canadian.

However, there are manufacturers who produce chocolate that, in my opinion, is not suitable for use in homemade baked goods. But the purpose of my research was not to reveal the quality of the chocolate presented on the consumer market, so I can only express my opinion about the chocolate that came to me from the retail network at random when buying chocolate for an experiment.

Chocolate is rightfully the favorite delicacy of mankind. It is a processed product of cocoa beans with sugar. The main raw materials for the production of chocolate and cocoa powder are cocoa beans - the seeds of the cocoa tree.

In order to become exactly the product that we consume today, chocolate had to go a long historical path.

To the question: is chocolate useful or not? I can confidently answer - yes, it is useful. After all, it contains 50-55% carbohydrates, 32-35% fat, 5-6% proteins. And also tannins (4-5%), stimulants - theobromine and caffeine (1-1.5%), trace elements Na, K, Mg, P, Fe, vitamins B1, B2 and PP and other equally useful components. Appendix No. 2 contains a table of the nutritional value of chocolate. But do not overuse the number of chocolate bars eaten.

List of used literature

1. Great Encyclopedia of Cyril and Methodius, / Under. ed. Muzrukov. 6th edition. M., - 2002.

2., Daring pastries and cakes. - M .: "Food industry", 19p., Ill.

3. About cooking from A to Z: Dictionary - reference book. - Minsk: Polymya, 1988 .-- 224p.

4. Shaternikov eat right. –2nd ed., Rev. and add. - M .: Agropromizdat., 1989 .-- 256 p.

6. Encyclopedia of Culinary Arts. Under. ed. N. Statsenko. - M .: "Tablets-S", 199s., Ill.

7.http: // www. *****

9.http: // ekonkmv. ***** / swiss. htm

Application

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Application

The nutritional value

(in brackets - the approximate share of the daily requirement,%)

	Milk chocolate, 100g
Proteins, g
Carbohydrates, g
Calcium, mg
Phosphorus, mg
Magnesium, mg
Iron, mg
Carotene, mg
Vitamin A, mg
Vitamin B1, mg
Vitamin B2, mg
Vitamin PP, mg
Calorie content, kcal

Application

Application

Application

	Determination of the mass of chocolate
	Determination of the volume of chocolate
	Melting

"Chocolate" - Chocolate. Dessert is very popular in South America. To get a fragrant and tasty chocolate, the beans need to be fried. The first chocolate factory of the ball was opened in Berlin. Machines do everything there. Europeans added sugar to chocolate to soften the taste. There, in 1756, industrial production of chocolate began.

"Where Does Chocolate Come From" - The Beehive is a home for bees. By origin, cocoa beans are divided into three groups: American; African; Asian. The main areas for the production of raisins and raisins are Uzbekistan and Tajikistan. Apiary - summer stay of bees in the fields. Raisins (from tur.? Z? M - vinigrad) - dried grapes with seeds. Honey.

"Placement and density of population" - Give a definition of the concept of "Ethnicity". Give an example of socio-economic factors in the distribution of the population. Population density. Natural. My geographic studies. Verification work. Territories with a favorable climate. Factors affecting the distribution of the population. Give an example of the largest language families in the world.

"Population density" - Oman, Paraguay, Belgium Vietnam, Laos, Cambodia USA, Japan, Germany Russia, Libya, Mongolia. Choose a group in which all countries have a low population density: Reasons determining the distribution of the population: Natural conditions and resources (relief, climate, soil, mineral resources ...) Features of the historical settlement of the planet Differences in the demographic situation Socio-economic conditions.

"Harm of chocolate" - Purpose: To find out the effect of chocolate on human health. Project name: Is chocolate good or bad? Output. The exact "dose" has not yet been established. Did you know that…. Substances in cocoa beans have a beneficial effect on the cardiovascular system. And in the books they write ... Physicians. Initially, chocolate was consumed only as a drink.

"Density of a substance" - The density of a substance. We will enter the measurement results in the table. The density of a substance is also the value of a fraction. For example, the density of cast iron is 7 kg / dm3. Recall that formulas can be transformed according to the rules of mathematics. The density of fresh water is 1 kg / l. Therefore, the mass of 1 liter of water is 1 kg.

Aims and Objectives The aim of the work is to study some of the physical properties of chocolate and its effect on humans. To achieve this goal, it is necessary to solve the following tasks: Study literary and electronic sources of information. To systematize and summarize the found material. Conduct a study of the individual physical properties of chocolate.

The history of chocolate The word "cocoa" first sounded like "kakawa" around 1000 BC, during the heyday of the Olmec civilization. The first European to taste chocolate was Christopher Columbus in 1502. Hernan Cortez, conqueror of Mexico, in 1526, on his way to report to the Spanish king, took with him a box of selected cocoa beans.

The history of chocolate In 1657, the first "Chocolate House" opens in London. In 1674, rolls and cakes were made from chocolate. The British Navy purchases more cocoa than the rest of Europe. In the 19th century, the first chocolate bars appeared, and Jacques Nehaus invented the first praline-filled candy.

Chocolate production The main technological stages on the production line: preparation of the main components (according to the recipe), mixing, grinding, tempering the chocolate, preparing the filling, molding the chocolate, dosing the fillings and additional ingredients (nuts, puffed rice), wrapping and packaging.

About the benefits of chocolate Cocoa contains substances that protect the arteries and, therefore, are beneficial for the cardiovascular system. They are called "phenols". These substances prevent the oxidation of cholesterol and prevent the deposition of fat on the walls of blood vessels. Half a bar of milk chocolate contains the daily dose of phenols.

About the benefits of chocolate White chocolate consists of harmless products - milk powder and cocoa butter. Thanks to the content of the latter, this dessert can not only be eaten, but also treated with it. Cocoa butter is good for throat ailments. So melt the white chocolate in the boiled milk and the medicine is ready.

Experimental results The chocolate melted in the following Nestle sequence - 3 min. Milka - 4 min. Babaevsky - 4.5 minutes Conclusion: the more vegetable fats in chocolate, the faster it melts. In our case, this is "Nestle". At a temperature of -10 ° C, chocolate freezes in the following sequence "Babaevsky" -1 min. "Nestle" -1.5 minutes Milka - 2 min. Conclusion: the more animal fats in chocolate, the faster it freezes. In our case, it is "Babaevsky".

Analyzing the graphs, we can conclude that the temperature change both during heating and during cooling is nonlinear. The melting and solidification points of the studied types of chocolate are the same and equal to 33 0 С, despite the fact that their density is slightly different.

During the experiment, I determined the density of the chocolate used. As can be seen from the data obtained, the density of different chocolates is different, which is explained by the different composition and percentage of cocoa powder. When determining the melting and solidification points, it was possible to obtain the data on which the graphs were plotted. According to the graphs, the melting and hardening temperature of chocolate was determined, which was 33 0 C. Conclusion

Chocolate Cocoa beans - American Asian African Types of manufactured chocolate, ordinary with or without dessert, with or without additions, with fillings white diabetic Quality Noble (varietal) Consumer (ordinary) Production process preparation of cocoa beans - roasting grinding, grinding molding cooling

Conclusion To the question: is chocolate useful or not? - I can confidently answer - yes, it is useful. After all, it contains 50-55% carbohydrates, 32-35% fat, 5-6% proteins. And also tannins (4-5%), stimulants - theobromine and caffeine (1-1.5%), trace elements Na, K, Mg, P, Fe, vitamins B1, B2 and PP and other equally useful components.

Investigation of the physical characteristics of some varieties of chocolate (Zhigalova Oksana. MBOU "Gymnasium No. 3" Belgorod. Supervisor: Kolkunova S.V.)

This work was carried out with the aim of studying some of the physical properties of various types of chocolate and its effect on human health. Since chocolate today is one of the most popular delicacies in the world, which neither adults nor children refuse.

The relevance of this work is due to the fact that in everyday life we ​​are faced with an infinite number of varieties and varieties of chocolate. They are different in taste, color, composition. Each manufacturer has its own method and technology for the production of this delicacy, and they try to make such products so that they are not only attractive, but also have their own special shapes, fillings and taste.

The practical significance of the work lies in the fact that performing instrumental studies of chocolate, there is a unique opportunity to establish patterns between the chemical composition, physical properties, taste and benefits for humans of this popular and beloved product.

How to check chocolate "for usefulness"? 25 - 30% of the content of cocoa beans in the bar indicates a rather low quality of this chocolate, 35 - 40% characterizes chocolate of average quality, 40 - 45% is present in the product quite good, but the content of cocoa beans from 45 to 60% speaks for itself for yourself - before you is an excellent chocolate bar that will do you good. There is still debate about whether chocolate is healthy, or whether it only adds extra pounds to us. Research by scientists has shown that cocoa contains substances that protect the arteries and, therefore, are beneficial for the cardiovascular system. They are called "phenols".

White chocolate is best for children who are allergic to cocoa. White chocolate consists of harmless foods - milk powder and cocoa butter. Thanks to the content of the latter, this dessert can not only be eaten, but also treated with it.

Since the moisture content of chocolate is low, up to 1%, it does not undergo microbiological deterioration and can be stored for a long time. For this reason, chocolate is often taken on long expeditions and hikes, as it reinforces and quickly restores human strength.

It also contains about 40 volatile compounds that determine an attractive, incomparable smell, and according to physiologists, this aroma has a beneficial effect on the psyche: it relieves irritation, pacifies, even restores peace of mind.

In the course of the study, the criteria for the selection of chocolate were determined, the melting and hardening temperatures of chocolate, the mass, volume of the chocolate and its density were calculated, as well as the melting and hardening time of the chocolate. For this, modern laboratory equipment was used in the physics classroom of our gymnasium.

Results of the work: Two experiments were carried out, but their result was different. As a result of the first experiment, it was not possible to determine the melting and hardening temperatures of the selected varieties of chocolate. The reason for this, in my opinion, was the poor quality of the chocolate used. The density of non-porous types of chocolate was calculated. The density of different types of chocolate is different, it is determined by the composition, and since the types of chocolate are different in their composition, then its density is different. In the second experiment, all the tasks that were set initially were completed and some of the features were clarified:

Liquid chocolate, gradually hardening, changed its color;

on cooling, the temperature of the chocolate decreased until it reached approximately 20 ° C, after which it remained constant for some time.

Each chocolate is ground in a different way, which is reflected in the amount of chips and the force applied. It can be assumed that it depends on its composition and density.

When analyzing the plotted graphs, the following was noticed:

1. The melting temperature of both types of chocolate is 20 ° C, this value was determined by the presence of a characteristic horizontal section.

2. The temperature change during heating and cooling is not linear.

3. Comparing the results obtained with the results of the Canadian experts presented in the article, similar dependences were obtained, and the melting and hardening temperatures of Russian and Canadian chocolate were approximately the same and equal to 20 ° C.

Comparing the results obtained with the results of a study of similar parameters of chocolate by Canadian scientists, we can say that Russian chocolate, of high quality, is not inferior in characteristics to Canadian.

However, there are manufacturers who produce chocolate that is not suitable for use in homemade baked goods.