Research work Where do the holes in the cheese come from? Where do holes in cheese come from?

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In all well-known food - cheese. Cheese is the oldest natural product that has been valued at all times both as an everyday meal at any time of the day, and as an exquisite accessory to a festive meal.

The beneficial qualities of this product are largely due to its nutritional value. Cheese consists of proteins, milk fats, minerals, extractives and vitamins that are vital and valuable for humans. Their concentration is almost 10 times higher than in the milk itself, from which, in fact, cheese is made. The protein that cheese is rich in is digested much better than the protein of fresh milk.

Extractive substances of cheese have a positive effect on the digestive glands and increase appetite. The protein that this product is rich in is an essential component of vital biological fluids human body(lymph and blood), as well as a key part of hormones and immune bodies.

Approximately 3% of the cheese is minerals, the lion's share of which is phosphorus and calcium. Along with them in different varieties cheese also contains iodine, iron, zinc, selenium, potassium and copper. The vitamin range is no less saturated: there are vitamins of groups B, E, C, A and D. It is known that vitamin B12 has an excellent effect on hematopoiesis, and B2 is a catalyst in the process of tissue respiration and promotes energy production.

Regular use of this product improves the condition of the skin, nails and hair (due to vitamin E) and promotes sharper vision (due to vitamin A).

There are many legends, tales, stories about the origin of cheese. One legend says that cheese was invented by shepherds who took milk with them when they went to graze flocks of sheep. Once a shepherd left milk in the sun, after a while he noticed that the milk began to thicken. A few days later, he drained the resulting liquid, and the thick lump that formed decided to try. I tried it, and I must say that he really liked this taste. This is how cheese was born.

In our country, cheese has been known for a very long time. The Slavs have long been preparing cheese obtained as a result of the natural coagulation of milk, i.e. without heat treatment, in the so-called "raw" way, hence the name cheese. Such cheese looked more like cottage cheese and differed from European hard cheeses. In addition, he was not particularly popular with the Slavs and was not their number one product. Naturally, this state of affairs did not contribute to the development of mass cheese making, so we can say with confidence that the history of cheese making in Russia began under Peter I.

Scientists and historians argue that the Slavs even paid tribute in cheese.

But the traditions of cheese making in Russia appeared only under Peter I. “Why are you giving me cheese eaten by mice?” - Tsar Peter I exclaimed in anger when in Holland he was treated to Dutch hard cheese for the first time. But, having figured out what was what and appreciating the taste of this outlandish product, Peter invited Dutch cheese makers to Russia so that the Russian people would also join European cuisine.

real start industrial production Our favorite delicacy in Russia is considered to be 1886, when a cheese factory was founded in the village of Otrokovichi, Tver province, under the leadership of Count Vereshchagin.

And by 1913, more than a hundred varieties of cheese were being produced in Russia, which were successfully exported and sold in other countries.

All this important and interesting information is easy to get from books on biology, cooking, from Internet sources. On the Internet, I was interested in the following fact: “There is a funny episode in one of the silent films with the participation of Charlie Chaplin. The great actor, playing the role of a waiter, before serving a plate of cheese, drilled holes in it ... with a brace. So he wanted to give out not very high-quality cheese for first-class - Swiss. Jokes are jokes, but the question of why there are “holes” in some types of cheese, including Swiss, is really curious.

The purpose of the work: to find out what processes: biological, physical or chemical, determine the appearance of holes in the cheese.

Object of study: "holes" in cheese.

Subject of research: processes leading to the formation of "holes" in cheese.

Work tasks:

1) To get acquainted with the history of the appearance of cheese and the processes of its manufacture.

2) Find out the nature of the appearance of "holes" in the cheese.

3) Make a conclusion on the work.

1. PROCESSES ACCOMPANYING THE PRODUCTION OF CHEESE

1.1. CHEESE COOKING TECHNOLOGY

Cheese - food product, obtained from raw milk using milk-clotting enzymes and lactic acid bacteria or by melting various dairy products and raw materials of non-dairy origin using melting salts.

The process of making cheese includes the following steps.

1. Milk pasteurization

2. Formation of a clot.

3. Cutting the clot

4. Obtaining cheese mass. As a result of the processes performed with cheese, a curd mass is obtained.

5. Cheese pressing. At the pressing stage, the cheese is laid out in special molds and pressed.

6. Cheese maturation. At this stage, the cheese should be transferred to the cellar, or some other special room for maturation.

Cheese production technology consists of a series of sequentially performed operations, shown in Figure 1.

Rice. 1. Scheme of cheese production technology

What processes: biological, physical or chemical, occur during the production of cheese and determine the appearance of holes in it?

1.2. BIOLOGICAL PROCESSES IN CHEESE PREPARATION

Biological processes include the destruction of technologically harmful pathogenic microflora, viruses and bacteriophages for cheesemaking. This is achieved by pasteurizing milk.

Milk is pasteurized immediately before being processed into cheese. The optimal mode of pasteurization of milk in cheese making is heating to a temperature of 70-72°C with a holding time of 20-25 s. In the case of increased bacterial contamination of milk, it is allowed to increase the pasteurization temperature to 76 ° C with the same exposure.

Biological processes occurring in cheese occur at the ripening stage and are determined by the vital activity of bacteria. In the production of cheeses, a pure bacterial culture is used as a starter, which includes lactic acid streptococci and lactic acid bacilli.

Ripening is the biochemical process by which cheese acquires its flavor. Bacteria, in particular propionic acid, play an important role in this process. As a result of their vital activity, acids are formed, which give the cheese a specific spicy taste and carbon dioxide, the bubbles of which we see as holes when cutting cheese. This theory was put forward in 1917 by the American scientist William Clark. He stated that the cause of holes, for example, in Swiss cheese are bacteria that, during their life cycle, produce carbon dioxide, which creates cavities inside the cheese. This theory quickly gained popularity and today considered the most likely.

The theory of an American researcher was called into question when, while studying Swiss cheese produced over the past 15 years, scientists from the Swiss National Center for Agricultural Research noticed that the number of holes in it was rapidly falling, and their size was decreasing.

What do you think could be the reason for this change in the canonical appearance of a cheese loved by many?

The answer was completely unexpected. During the traditional milking of cows, microscopic particles of straw get into the bucket, which, apparently, are a necessary component of the vital activity of bacteria, which subsequently lead to the formation of huge cavities inside the cheese cylinder (the larger the particles, the larger the eyes). Today, cheese producers are increasingly moving away from centuries-old traditions, switching to automated production systems. Thanks to this, the milk is devoid of foreign impurities, as a result of which the cheese is deprived of traditional holes.

Biological processes are closely related to chemical processes occurring in living organisms.

1.3 CHEMICAL PROCESSES IN PREPARING CHEESE

Chemical processes are processes in which other, new substances with certain properties are formed from some substances. Signs of chemical reactions are:

1. Gas release. 2. Change in smell and taste.

3. Precipitation or dissolution of the precipitate. 4.Color change.

5. Allocation or absorption of heat.

After analyzing the information about the main stages of cheese production, we can distinguish the following chemical processes occurring in cheese:

chemical process		Sign of reaction
Enzymes of abomasum and lactic acid bacteria carry out hydrolytic cleavage of proteins. In particular, chymosin catalyzes the reactions of hydrolytic cleavage of peptide bonds in casein with the formation of peptides, which are degraded to amino acids under the action of lactic acid bacteria enzymes. Some of the amino acids undergo decarboxylation and deamination by bacterial enzymes. As a result, CO 2 and NH 3 can accumulate in the cheese mass, as well as carboxylic, keto and hydroxy acids, amines, which give a certain taste and aroma to the cheese (change in smell and taste).	cheese maturation	Gas evolution
Lactic acid bacteria ferment milk sugar (lactose) into lactic acid, which changes the smell. Enzymes of microflora are able to hydrolyze lipids. At the same time, free radicals are found in all cheeses. fatty acid(oil, valerian, caproic, caprylic, etc.), the content of which gives the appropriate taste and smell to the cheese.	Milk maturation cheese maturation	Change in smell and taste
Partial denaturation of casein, as well as partial loss of calcium salts (from soluble salts they pass into a water-insoluble form).	Pasteurization	Precipitation
After a solution of a coagulating enzyme (chymosin) is introduced into milk, protein flakes are first formed, and then a continuous clot. Under the action of rennet, milk coagulates in two stages: at the first stage, casein (milk protein) is converted into paracasein (enzymatic process), at the second stage, paracasein is coagulated under the influence of calcium ions (colloid-chemical process). In the production of cheese, pepsin, an enzyme isolated from the fourth section of the stomach of adult ruminants, can also be used. However, pepsin is less selective for caseins than chymosin.	Rennet coagulation	Precipitation
To prepare cheese (formation of a milk clot), from 10 to 40 g of anhydrous CaCl 2 per 100 kg of milk is added to milk. At the same time, phosphorylated by the remains of casein and calcium, with the participation of rennet, enter into chemical interaction.	Milk maturation
Lactic acid undergoes further chemical transformations, resulting in the formation of calcium lactates and paracasein monocalcium salts, which swell easily, which contributes to the formation of an elastic cheese texture. Lactic acid converts the mineral salts of cheese and the phosphorus of inorganic salts into a water-soluble state.	Milk maturation cheese maturation	Dissolution of precipitation
All of the above chemical processes (except for the pasteurization stage) are exothermic.	Milk maturation cheese maturation	Heat generation

Color change. The color of the cheese depends on the nature of the milk, and not on the chemical reactions that take place in it. For example, the milk of sheep, Asiatic buffalo and some breeds of goats does not contain the yellow pigment b-carotene or contains very little of it; accordingly, cheeses obtained from such milk, as a rule, have a white color. Part cow's milk includes b-carotene; its amount depends on the time of year, the breed of the cow and her diet, and the natural color of the cheese obtained from cow's milk varies from straw to yellow.

1.4. PHYSICAL PROCESSES IN PREPARING CHEESE

Physical processes are processes that do not accompany the formation of new substances, while they can change the shape, volume, and state of aggregation of a substance.

Have you noticed that in most varieties of cheese, the “holes” - “eyes” are spherical in shape? It turns out that this is explained by a physical process, which is based on Pascal's law:

the pressure exerted on a liquid or gas is transmitted to any point without change in all directions.

First prepare the "dough" for the cheese. Then the resulting mass is compacted under high pressure and filled with special forms. The cheese heads formed in the molds are taken out and placed in warm chambers for maturation. During this period, the cheese "ferments". Inside the compressed, but still soft “dough”, carbon dioxide is formed, which, accumulating, is released in the form of bubbles. The more carbon dioxide, the more bubbles inflate. Then the cheese hardens, and a picture of the internal “breathing” of the fermenting cheese is imprinted inside it in the form of inclusions of carbon dioxide bubbles.

As for the shape of the formed cavities, then, firstly, according to Pascal's law, the pressure in the bubbles is equally transmitted in all directions, and secondly, the "dough" at this moment is similar to a liquid in its elastic properties. Therefore, the bubbles are inflated strictly spherical shape. Deviation from this rule will mean that in some place inside there are seals or, conversely, voids in the “dough”. The harder the cheese, the less the inner bubble swells, the smaller the hole size.

Additional physical changes that occur in foods, including cheeses, include wetting and drying. These processes change the state and properties of products, and also affect the activity of chemical and biochemical processes. Drying and wetting lead to darkening of the mass of the product. These changes can be slowed down by observing the appropriate temperature regimes.

According to physical and chemical processes, cheeses are divided into processed and brine.

Processed cheeses are a product obtained from mature high-quality rennet cheeses by melting them at a high temperature, in the chemical composition of which there is a high content of proteins, lipids, organic acids and other compounds, compared with rennet cheeses.

At the core of production processed cheese the property of rennet cheeses to melt at a temperature of 45-50 ° C is used, and to liquefy at a higher temperature, while the final stage of production is the production of a high-calorie food product.

Before melting, the cheese is crushed; the small particle sizes of the cheese mass make it possible to form a more homogeneous mass of the product during melting of the cheese. Usually the cheese is melted at 80-85 "C for 15-20 minutes.

During melting, part of the moisture may evaporate, so butter, milk, buttermilk, etc. are added to the melted mass to soften it. Sugar, salt, ham, nuts, etc. are added as fillers. palatability product and its consistency. When melting the cheese mass, the physicochemical properties of proteins change. In this case, the poorly soluble calcium paracaseinate passes into the well-soluble sodium paracaseinate.

When melting cheeses, salts of phosphoric (Ca 2 HPO 4, NaH 2 PO 4, H 3 PO 4) and citric (sodium citrate) acids are added to the melted cheese mass, which can bind to casein and paracasein, increasing the aggregate stability of proteins. The use of acidic salts can lower the pH of the cheese, which affects the consistency of the product.

Brine cheese is a type of cheese that is matured and stored in brine, so it does not have a rind. Pickled cheeses contain up to 7% salt. TO pickled cheeses include cheese, suluguni, Adyghe cheese and others.

Cheese. Brynza cheese is made from cow's and sheep's milk or from a mixture of cow's, sheep's and goat's milk.

For the production of cheese, the acidity of cow's milk should be 22 ° C, sheep's - 21-28 ° C. Pasteurization of milk is carried out at 72-74°C (instant pasteurization) or within 10 minutes at 68-70°C.

Calcium chloride is added to pasteurized milk. After mixing, the mixture is cooled to 27-30°C, and then 0.5-0.7% of the total volume of bacterial starter for cheeses is added. The formation of a milk clot occurs within 75-90 minutes. When unfolding the milk clot, its edges should be even, and the whey released at the same time is transparent and slightly greenish.

The upper layer of the clot 2-3 cm thick is removed and set aside. The rest of the clot is cut with a knife into squares, and then the pieces are transferred to a dense fabric, the clot is pressed. To do this, a load equal to its weight is placed on the clot for 2 hours, and then the weight of the load is increased by 1.5-2 times. The total duration of pressing depends on the acidity and consistency of the clot and can last for 2-4 hours. The pressing ends only when the whey ceases to stand out from the clot. The pressed layer is cut into squares 10-15 cm in size, which are placed in an 18% sodium chloride solution and kept in this solution for 8 to 16 hours at 10 ° C, turning over. Then the pieces of cheese are placed in barrels, pouring 15% sodium chloride solution. Ripening of cheese is carried out for one month at 12-15°C. Ready-to-eat cheese is stored at 4-6 °C.

Cheese is produced with a content of 40-50% lipids in the dry matter of cheese, at 49-52 % humidity and 4-8 % salt.

Product specifications. Appearance. Brynza cheese has a clean surface without rind. Slight mucilage of the surface, slight deformation, minor cracks (not more than

3-4 mm in width).

3. CONCLUSION

As a result of my work, I got acquainted with the history of the appearance of cheese and the processes of its manufacture.

She found out that as a result of complex microbiological, biochemical and physico-chemical processes, products are formed in cheese that determine its organoleptic characteristics. Cheese acquires along with the general cheese flavor and smell specific for each type of cheese flavors and aroma, the corresponding pattern (eyes) or its absence.

“Holes” - “eyes” in cheese are bubbles formed due to the release of carbon dioxide, ammonia, and partially other gases, such as hydrogen, during fermentation. Among them, carbon dioxide accounts for 90%. At first, gases dissolve easily in cheese whey, and when supersaturated solutions are obtained, they begin to accumulate in the gaps between cheese grains. They push the cheese mass apart, as a result, cavities are formed - eyes, the protein mass is compacted and moisture is released, which accumulates in the eyes, forming a “tear”.

The number and nature of the eyes form the pattern of the cheese. With the rapid formation of gas, the eyes will be small - with a diameter of 0.3-0.5 cm (small hard cheeses), and with slow formation - large - with a diameter of 1-2 cm (large hard cheeses). In large cheeses (such as Swiss), eyes are formed 20-25 days after manufacture, and sometimes later. They have a regular round shape, filled mainly with carbon dioxide and a small amount of nitrogen and oxygen. Carbon dioxide is formed mainly under the influence of propionic acid fermentation. In small cheeses, the eyes are small, frequent, round in shape. If the fermentation process is normal, the pattern has rounded eyes, evenly spaced. If the normal fermentation process is disturbed, a pattern is formed that is uncharacteristic for a particular type of cheese.

The presence of eyes depends on the starter used to make cheese, heat treatment and manufacturing technology. I found out that the appearance of “holes” in cheese is due to a complex of biological, physical and chemical processes.

LIST OF USED SOURCES AND LITERATURE

1.Internet resources:

1) http://www.topauthor.ru/otkuda_v_sire_dirki_b244.html

2) http://nsportal.ru/nachalnaya-shkola/raznoe/2014/02/07/proekt-otkuda-v-syre-dyrki

3) http://pandia.ru/text/79/077/23490.php

4) http://doseng.org/interesnoe/97706-otkuda-v-syre-berutsya-dyrki.html

5) http://www.bestreferat.ru/referat-272013.html

6) http://works.doklad.ru/view/JY4nEj9HpU4.html

Sometimes questions come to mind, the answers to which are logical from the point of view of experts, but not obvious. Why is the sky blue and the grass green? Why does it get dark at night? And why are there such big holes in Swiss cheese? How the cheese got its distinguishing feature, for which (at least in part) he is loved all over the world - we tell below.

Holes in cheese as part of production

The classic version says that the holes in the cheese appear due to the content of certain bacteria in it. According to cheese historian Paul Kindstedt, it all starts with Swiss cheese coming from the Alps. And although the Alpine landscapes look picturesque on the package, it is important to understand that these are still mountains that left the work of cheesemakers in a certain medieval sense for a long time. The cheese had to make a long journey, and for this it was necessary that the head of cheese remained as dry as possible during the delivery process.

In an attempt to optimize the process, cheese dairies have developed new tools to maintain higher temperatures, with special presses to remove excess moisture from the cheese. The result was a product with the correct elasticity and sufficient low content acids and salts, which was achieved by increasing the number of Propionibacterium freudenreichii batteries. It is the metabolic by-products of these bacteria that give Swiss cheese its nutty taste, and also make holes in it.

Although holes were inevitable in the production of quality cheese, over time they have acquired a special value. As chemist and author of The Science of Cheese, Mike Tunick, points out, holes are what people have been waiting for. Imagine how upset we would be if the cheese suddenly became less "leaky". No big deal in terms of utility, but the product would definitely look less appetizing as time has made us love the look of it.

But - oh, the horror - it really happens. Walter Bisig, of the Swiss government research center Agroscope, notes in an interview with The New Yorker that over the past 10-15 years, Swiss cheese has become less big-eyed. Naturally, Bisig and his colleagues in the food processing technology group took an interest in what was going on.

Hay makes holes in cheese

The main problem was that there were too many things that could affect the texture of the cheese. According to the University of Iowa experts, cheese sometimes suffers from an overabundance of small holes, irregular holes, or the “blindness” effect, when there are holes in the cheese, but on the cut they are covered with a thin layer of cheese mass. Each of these deficiencies has a number of possible sources, including cottage cheese, which may be too acidic or resistant to storage temperature, causing disruption in bacterial production.

Another problem, besides the volatility of the cheese itself, was that no one until now knew how the holes decide where to appear. One theory, for example, claimed that carbon dioxide accumulated at "weaker points in the cheese matrix". Other experts were sure that the "eyes" formed around some kind of nuclei, like raindrops stick to dust specks.

In the end, it was possible to establish that the size and number of holes depends on the time the cheese appeared. So, more "blind" cheeses are born in summer, and more "big-eyed", on the contrary, in winter. This made it possible to see a connection with the fact that cows mainly eat fresh grass in summer and hay in winter.

In this way, the researchers came to the “hay theory”, which says that it is the microscopic particles of hay in milk that become the nuclei around which holes form. Experiments with the production of cheese on pure milk filtered from any impurities confirmed it - there were almost no holes in the cheese. Swiss scientists from Agroscope suggest that hay affects not only the presence or absence of holes, but also their characteristics: the less hay in the milk, the larger they will eventually turn out.

“Why are you giving me cheese eaten by mice?” - Tsar Peter I exclaimed in anger when in Holland he was treated to Dutch hard cheese for the first time. But, having figured out what was what and appreciating the taste of this outlandish product, Peter invited Dutch cheese makers to Russia so that the Russian people would also join European cuisine. Although, it should be said that the Slavs have long been preparing cheese obtained as a result of the natural coagulation of milk, i.e. without heat treatment, in the so-called "raw" way, hence the name cheese. Such cheese looked more like cottage cheese and differed from European hard cheeses. In addition, he was not particularly popular with the Slavs and was not their number one product. Naturally, this state of affairs did not contribute to the development of mass cheese making, so we can say with confidence that the history of cheese making in Russia began under Peter I.

However, cheese production did not take off. First, small cheese dairies appeared, in which Dutch masters were involved. And the first cheese factory was built in the village of Lotoshino, Tver province, on the estate of Prince Ivan Sergeevich Meshchersky, only in 1795 (70 years after the death of Peter I). The factory was managed by the Swiss master cheese maker Johannes Müller, who established the production of Swiss cheese on Russian soil, called Meshchersky cheese. Following the example of Prince Meshchersky, others organized small-scale cheese factories on their estates, which, however, eventually ceased to exist.

Thus, there was no large-scale industrial production of cheese in Russia for a long time. And only in 1866, at the insistence of the Russian educator, public figure, member of the Moscow Society of Agriculture, Nikolai Vasilyevich Vereshchagin, the Imperial Free Economic Society opened a cheese factory in the village of Otrokovichi, Tver province. Then, through the efforts of the same N.V. Vereshchagin, cheese and butter artels began to be created in the villages, which made cheese and butter in industrial scale. Therefore, it is 1866 that is considered the beginning of the industrial production of cheese in Russia. And by 1913, about a hundred varieties of cheese were already being produced in Russia, many of which were even exported.

Well, what about the holes that so angered Peter I, where do they come from in cheese? And everything is very simple. We all know that cheese is made by fermenting milk, aided by lactic acid bacteria. So, the movement of these bacteria causes an increased production of carbon dioxide. The released carbon dioxide accumulates in the microvoids of the ripening cheese, creating a kind of bubbles that cannot rise to the surface due to the viscous consistency of the cheese mass. Eventually, they harden, resulting in holes in the cheese, but they do not form immediately, but on the twentieth or thirtieth day of cheese maturation. By the way, master cheese makers and true cheese connoisseurs will never say “holes”, they call the resulting holes “eyes”.

And the shape and size of the eyes depends on the properties of the cheese mass, the chemical composition of the gases formed and the intensity of their accumulation and release. In addition to carbon dioxide (50 - 90%), nitrogen (6.3 - 48%), oxygen (up to 0.2%) and even hydrogen (up to 3%) can be released during the ripening of cheese. For example, with the rapid release of carbon dioxide in the cheese mass, many small eyes are formed, as in Dutch cheeses, and with a slow release, large eyes are obtained, but in small quantities, an example of this is Swiss cheeses. The world-famous Swiss Emmental cheese has eyes two to four centimeters in diameter. And there are completely blind cheeses, without eyes. These include very hard, aged cheeses such as Parmesan and most soft cheeses.

Thus, cheese eyes are bubbles formed as a result of the release of carbon dioxide during the fermentation process, and the shape and number of eyes depends on the enzymes used to make the cheese, heat treatment and cooking technology. As you can see, cheese eyes do not form randomly, this is a completely controlled process. In many cheese dairies, ripening cheeses are even subjected to a special ultrasound examination to see if there are any flaws in the formation of eyes, whether they have the correct shape and quantity.

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Rusakova Eva, 3rd grade student "A"

Eva carried out the research work "Why there are holes in cheese" under my supervision. The material was collected from literature, the Internet, processed. Together we decided what kind of research to conduct. Eva and her mother made cheese at home. With this work, Eva performed at the city competition research work, took first place. The work was sent to the website of the Academy, received the title of Laureate.

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MUNICIPAL EDUCATIONAL INSTITUTION "LYCEUM № 8"

CITIES OF NOVOALTAYSK ALTAI TERRITORY"

URBAN RESEARCH COMPETITION

WORKS AND CREATIVE PROJECTS OF PRESCHOOL CHILDREN AND JUNIOR SCHOOL CHILDREN

« YOUNG RESEARCHER IN HOME TOWN»

3rd grade student

Scientific adviser: Matveeva Nina Vasilievna,

primary school teacher

City of Novoaltaisk, 2010

Object and subject of research…………….…………………………………..3

Hypothesis………………………………………………………………………………3

Purpose and objectives……………………………………………………………………….3

Methods …….…………………..………………………………………………....3

Study plan ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………3 - 4

Relevance of the chosen topic……………………………………………………4

The history of the origin of cheese………………………………………………….5 - 6

Why are there holes in cheese? ......................................... 7 - 8

How cheese is made…………………………………………………………………8 – 10

Experiment. Making cheese at home……………….10 -12

Cheese recipes………………………………………………….12 -13

Conclusion…………………………………………………………………………… 13 - 15

Literature used………………………………………………….. 16

Object of study:

Different types of cheese

Subject of study:

Making holes in cheese

Hypothesis:

Holes in cheese can form during the cheese making process during fermentation and bubble production.

Purpose of the study:

Find out why some cheeses have holes and others don't.

Tasks:

learn to use additional literature;
learn to work on the Internet;

study material on the production of cheese;

describe the search activity;

make cheese at home

summarize the findings.

Methods:

observation
experiment
generalization

Study plan:

collect material on the production of cheese;
study scientific and reference literature;
experiment on making cheese at home;
draw conclusions;
write a report;
to make a presentation

Relevance of the chosen topic.

Why do we want to find out?

One two three four -

Let's count the holes in the cheese...

If there are many holes in the cheese,

so it's delicious cheese.

If it has one hole

So it was delicious yesterday!

I love cheese very much, and my mother often buys it. Cheese is one of the most nutritious foods. And if you carefully consider it, you can see holes and for some reason they are of different sizes.

I thought, why are there holes in the cheese?

Maybe they ate half of the mouse? After all, not all cheeses have holes.

Maybe it's the former bubbles?

But what if it's shot from a gun and the holes are round.

I started looking for answers in books. From them I learned that cheeses are different: hard, soft. Some with holes, some without.

It turns out that these are not holes, but eyes. The eyes “open” at the cheese during its aging, in the process of fermentation, under the action of lactic bacteria, carbon dioxide is released, which forms small cavities in the cheese mass, similar to bubbles. This happens during production. hard varieties cheese.

Why is it so: some cheeses have large, round eyes, reaching 4 cm in diameter, while others have tiny, barely noticeable ones, and others don’t have them at all?

From the Internet I learned:

The word "Cheese" (Cheese) comes from the Latin caseus, from which the word "casein" also came - the main component of milk, the protein that is the basis of cheese.

Early history

Cheese was a common food item in ancient times. Scientists believe that people began to eat it as early as the 8th millennium BC, when the sheep was domesticated. It is believed that the process of making cheese was found in the Middle East or by nomadic Turkish tribes living in Central Asia. For them, the task of preserving food on long journeys was relevant, in addition, for this they often used skins and internal organs animals. Milk in such "reservoirs" (acorns) was curdled into cottage cheese, and under certain circumstances it could well have turned out to be a product - a prototype of modern cheese.

The first archaeological confirmation of cheese-making came from the excavations of ancient Egypt in the form of rock frescoes in caves dating back over 2000 BC. Most likely this cheese was very sour and salty, since a large number of salt was necessary to improve the preservation of cheese in the hot Egyptian climate.

History of cheese

There are many legends about the origin of cheese. The most common and plausible of them is the legend about the Arabian merchant Kanan, who lived four thousand years ago. One fine morning, he set off on a long journey, taking food and milk with him. The day was sultry, and after a while the merchant was exhausted. He stopped to quench his thirst, but instead of milk, a watery liquid flowed from the vessel. At the bottom, a white dense clot was found. Kanan tasted it and was pleased with the taste. Being a simple and unsophisticated man, the merchant shared his discovery with his neighbors. Soon the secret of making cheese became known to many nomadic tribes. Over time, from Arabia, cheese came to Europe.

The ancient Greeks had their own explanation of the origin of cheese, more like a beautiful fairy tale. They believed that Artemis, the goddess of the hunt and the patroness of animals, taught people how to make cheese. And even the gods themselves feasted on cheese at feasts, washing it down with wine. Not surprisingly, some ancient religious cults were associated with cheese. The inhabitants of Crete, for example, sacrificed special flat cheeses to the gods. And the priests of Athens were strictly forbidden to try this product. Cheese was also known to the Assyrians. They explained the greatness of their queen Semiramis by the fact that the birds steal cheese for her from the shepherds.
The ancient Romans also revered cheese. They were sure that it had a beneficial effect on digestion and used it as an antidote for poisoning. Cheese is mentioned in Homer's Odyssey by Virgil. The "Natural History" of Pliny the Elder lists the types of cheese brought to Rome. It is characteristic that cheese is invariably praised as a life-giving, healthy, even "divine" product.

The oldest recipe in the world is 2000 years old. It belongs to the Persians. It states that cheese should be made from "sheep's or cow's milk, dried in the sun and flavored with fragrant roots." One of the old English recipes is also contained in the cookbook of the court cook of King Richard II.

Why are there holes in cheese?

Where did the word come from"cheese"?

We can say that the word "cheese" has always been. It was used by our ancestors, but they meant cottage cheese. Cheese has become known as cheese only recently. Why "cheese"? From the word "raw", "whey". Serum is like this curd product. There is a technology by which milk (which becomes whey) is used to make cheese. And so it stuck: from cheese comes cheese.

Cheese It's like very, very dense milk. Cheeses are made in special factories - cheese dairies. Cheeses are soft and hard, brine and processed, they even come with mold. Dutch cheeses, French, Italian, Swiss, Greek. Almost every country boasts its own cheese.

Cheese - a highly nutritious food product made from curdled (sour) milk. Usually light yellow in color, it happens both with "holes" (cavities) and without them.

It turns out that the holes in the cheese are formed due to the release of carbon dioxide during the fermentation process. To coagulate milk and obtain a cheese clot in cheese making, different starter cultures are used: either lactic acid (large holes), or rennet extract(small holes), and sometimes both. The sourdough contains bacteria. Bacteria are very, very small. They can only be seen with a microscope. As the cheese matures, acidic bacteria live in it and produce carbon dioxide. The gas cannot get out of the dense cheese and puffs out, which causes air bubbles of different sizes to form inside the cheese. When we cut the cheese into slices, the bubbles are cut and holes are obtained, or, as they are also called, eyes.

The formation of eyes depends on the elasticity of the cheese mass and the maturation of the cheese. Microorganisms that live in cheese and participate in the fermentation process release carbon dioxide and carbon dioxide is formed. The more seasoned and harder the cheese, the larger the hole.

The presence of holes of different sizes is characteristic feature many cheeses. Previously, it was believed that they appear due to fermentation milk sugar. Later, as a result of research into cheese cases, the masters found out that milk sugar disappears almost in the first days of its production,holes begin to form only on the 20th day.From that moment on, during the fermentation of milk salts that react with acids, bacteria, calcium acetate and carbon dioxide are formed. Accumulating in small voids of cheese, carbon dioxide forms holes. But their size and shape depend on the chemical composition of the gases in the holes. So, for example, in the world-famous Swiss cheese, the diameter of the hole can be 2 cm. The concentration of gases is not the same in different varieties of cheese.

How is cheese made?

My mother and I called the butter and cheese factory in Barnaul, we wanted to go and see the cheese-making technology. But we were told that they could not disclose their manufacturing technology. Therefore, we found the answer to our question on the Internet.

First prepare the "dough" for the cheese. It is different for each type of cheese. Then the resulting mass is compacted under high pressure and filled with special forms. The cheese heads formed in the molds are taken out and placed in warm chambers for maturation.

During this period, the cheese "ferments". Inside the pressed, but still soft “dough”, carbon dioxide is formed, which, accumulating, is released in the form of bubbles. The more carbon dioxide, the more bubbles inflate. Then the cheese hardens, and inside it appears a picture of the internal "breathing" of the fermenting cheese in the form of bubbles of carbon dioxide. The pressure in the bubbles is equally transmitted in all directions. Therefore, the bubbles are strictly round in shape. Deviation from this rule will mean that in some place inside there are seals or, on the contrary, voids in the “test”.

The harder the cheese, the less the inner bubble swells, the smaller the hole.

Some types of cheese are not subjected to high pressure

(Russian), in them the release of carbon dioxide occurs in the already existing voids of irregular shape. Such cheeses in the context do not have the correct shape of frozen bubbles, but rather an intricate pattern.

"Big-eyed" cheeses are often the subject of ridicule. Peter I, being in Holland, was treated to cheese. He was indignant when he was given an outlandish product with large holes. He exclaimed: "Why are you giving me cheese eaten by mice"

But in 2001, the American authorities set the maximum diameter of a cheese eye no more than 2 cm.

Exist different types cheeses on different taste. Cheese acquires its flavor during ripening and cooking. Ripening takes place in special storage facilities under strict control of temperature and humidity.

Having learned from the Internet how cheese is made, I asked my mother a question:

Can you make cheese at home?

It turned out that it is possible.

Making cheese at home

For cheese makingat homeI took the following products:

1 liter of milk;
1 kilogram of cottage cheese;
2 eggs;
100 grams butter;
1 teaspoon of soda;
2 teaspoons of salt.

I take cottage cheese and milk, mix. When the whey appears, I throw it into a colander. I'm waiting 40 minutes. I take butter, soda, salt and add to the resulting mass. Once again, mix everything together and put on low heat.

Stirring, cook until thickened (about 40 minutes). I pour everything into a round dish - a saucepan or a plate and, when it cools down, I put it in the refrigerator.

If desired, you can use a washed milk carton if you want the cheese to be in the shape of a brick.

To taste, this cheese resembles Suluguni cheese.

Try it, very tasty!

But in my cheese, which I made, there were no holes. Probably due to the fact that when making cheese at the factory, the formation of bubbles occurs on the 20th day, and I made my cheese in 2 hours.

I can offer you some more recipes(taken from internet)

1 kg cottage cheese, 1 liter milk, 100 g butter, 50 g vegetable oil, 1 teaspoon salt, 2 eggs, 1 teaspoon baking soda, 3 tablespoons vinegar.

Heat milk, add cottage cheese to it. Boil the mass for 10 minutes, stirring constantly. When the cottage cheese curdles, put it on cheesecloth and wring it out well. Then put the squeezed cottage cheese in a clean saucepan, add butter, eggs, salt and mix everything. Place back on medium heat and bring to a boil, stirring occasionally. At the end of cooking, add soda and vinegar and mix well again to make homogeneous mass. When the cottage cheese begins to lag behind the walls - homemade cheese ready. Pour the cheese into a mold and refrigerate to set.

The cottage cheese is thrown onto a sieve lined with a piece of clean cloth so that the whey is glass. Then it is transferred to a bowl, sprinkled with fine salt (1 tablespoon of salt per 1 kg of cottage cheese) and ground until a uniformly crushed soft mass is obtained or passed through a meat grinder 2-3 times. If the cottage cheese is low-fat, you can add a little cream or swept. The mass is placed in linen bags, tightly stuffing 500-800 g of a well-ground mass, after which the bags are tied and put under oppression, covered with planks. Cottage cheese is pressed for 5-10 hours without overdrying it. Then place in the refrigerator from time to time turning. Wash when mold appears

salted water and dried in a draft.

Freshly prepared cottage cheese is passed together with salt twice through a meat grinder and left for 5 days in a dry room. The yellowed cottage cheese is mixed again, transferred to a greased pan and boiled over low heat, stirring all the time, until a homogeneous liquid mass is formed. The full mass is poured into small saucepans or other dishes. After it cools and hardens, the cheese is ready.

To prepare 1 kg of cheese, take 8 ½ cups fat-free cottage cheese, 2 ½ tablespoons butter or ghee, 4 teaspoons of baking soda and 3 teaspoons fine salt. The discarded cottage cheese is passed through a meat grinder several times. Cottage cheese is placed in the dish, sprinkled with half the amount of salt and soda on top, and then they begin to slowly heat it up, continuously stirring with a wooden spatula. If during the heating process whey appears on the surface of the curd and near the walls of the dishes, the dishes are covered with a lid, removed from heat for 10-15 minutes, then the settled whey is removed. If the whey cannot be separated, the rest of the soda is added to it and the mixture continues to be heated. After the cheese mass melts well and thickens somewhat, melted butter is added. The remaining salt is put 15-20 minutes before the end of cooking. The finished cheese mass should be a homogeneous stretching mass. Pour the cheese mass into a mold or other dish, greased with oil and take it to a cold place. To remove the chilled cheese from the dish, it must be immersed in hot water for a few seconds.

Conclusion:

Thus, one of my hypotheses was confirmed. Indeed, the eyes in cheese are bubbles formed due to the release of carbon dioxide during the fermentation process. The presence of eyes depends on the starter used to make the cheese, heat treatment and manufacturing technology.

Mice version.

Tell,

Who ruined the cheese?

Who put it on

So many holes?

Anyway,

Not me! -

hastily grunted

Pig.

Mysterious! -

Gus exclaimed. -

A ha-guess

I don't take it!

The sheep said, almost crying:

It's a freakin' hard task!

Everything is incomprehensible, everything is foggy -

Ask better

At Baran!

All evil comes from cats! - said,

Sniffing the cheese

Yard dog. -

Like two times two is four

From them and holes in the cheese!

And the Cat snorted angrily from the roof:

Who drills holes?

Clearly - mice!

But then God brought the Crow.

Hooray!

She will solve the issue.

After all, as you know,

She has

For cheese

Special flair!

And here is the order

Crow

Check case

Comprehensive...

Hurrying to unravel the mystery of holes,

Crow

deepened

In cheese.

Here

holes

wider,

Wider...

Where's the cheese?

Forget cheese!

Robbery! Robbery! Ruin! A shame!

Flew up the fence

Crow

And said

Offended:

Well, this is, you know, nitpicking!

You

Interested

Holes?

So what's the deal?

I ate cheese

And the holes

All! -

Remaining intact!

This was the end of the argument.

And that's why

Still,

Alas,

No one knows

In the world,

Where is it anyway

Holes in the cheese!

One two three four -
Let's count the holes in the cheese.
If there are many holes in the cheese,
So the cheese is delicious.
If it has one hole
So it was delicious yesterday.

References:

P.V. Shilov “Cheese, cottage cheese, milk”.

Profisdat; 2007.

O.A. Aleksandrova "Let's count the holes in the cheese"

Dragonfly - Press, 2005.

Materials from the Internet.