Bulgarian Yogurt

The Unique Healing Properties of Bulgarian Yogurt For a Healthy Diet – Part 1

Research lately has shown that the traditional Bulgarian cuisine of the late 1800s and early 1900s was very close to the so called Mediterranean diet. Furthermore, food traditions in all Balkan countries show how very close they are, which enables us to speak of healthy Balkan food or Balkan diet. Food traditions of the Balkan peoples meet the important criteria of healthy diet.

The Bulgarian sour milk ( yogurt ) is a typical example of the Bulgarian contribution to Balkan healthy diet. Ilia Ilich Mechnikov, a distinguished Russian and French biologist, had a hypothesis that Bulgarian highlanders owe their longevity to yogurt.

In the beginning of the 20th century, the world famous Russian biologist, Nobel laureate, Ilia Ilich Mechnikov (1845–1916), began work in the most famous at that time the Luis Pasteur institute in Paris. He thought that aging is a disease like all other diseases. Mechnikov believed that protein substances rot in the colon, and as a result toxic amides harmful to man are produced. They are absorbed by the body and cause changes in the tissues of the arterial walls. As a result senile changes occur in the body leading to unduly early death. Mechnikov was certain that the harmful influence of these microorganisms can be reduced by suitable lactobacilli.

Mechnikov gathered data from 36 countries and found that most centenarians live in Bulgaria, four in a thousand people. He explained that with the regular consumption of the Bulgarian yogurt. Thus Mechnikov was the first to put on a strict scientific basis the nutritional, dieting and healing properties of the Bulgarian  yogurt  and attract the attention of the world public to it. He was convinced in the excellent properties of the Bulgarian  yogurt  as a food product and during the last ten years of his life he took Bulgarian  yogurt  regularly.

The first scientist who studied the micro flora of the Bulgarian  yogurt  was the Bulgarian Stamen Grigorov (1878-1945), a medical student in Geneva. In 1905 he described it as consisting of one rod and one ball lactic acid bacteria. In 1907 the rod bacterium was called Lactobacillus bulgaricus, and the ball bacterium  Streptococcus thermophilus.

The well-known Bulgarian biochemist, Professor Assen Zlatarov, wrote, “ yogurt is the longevity elixir. It is a milk product which is received by milk fermentation. There are two basic microorganisms which take part in the fermentation process:  Lactobacillus bulgaricus and Streptococcus thermophilus, which are in a symbiotic relationship; it is essential for the survival and efficacy of the two bacteria only that they should be together. Fermentation is not possible with only one bacterium; each of them has its role in the fermentation process. This fermentation process ends in a natural way through cooling. If you keep the milk out of the fridge for several days, fermentation continues and the milk becomes too sour.

The history of yogurt


We do not have exact data about the origin of the Bulgarian yogurt. One of the theories is connected with the Thracians, an ancient tribe who inhabited the land of Bulgaria. Nowadays Thrace is a plane in south Bulgaria. In the ancient times this land had fertile soil, rich vegetation and lush pastures. The Thracians had plenty of sheep. They noticed that sour milk can be preserved longer than fresh milk. So they started adding a little sour milk to the fresh milk and received leavened sour milk or “prokish”, which means “sour”.

Another theory is connected with the proto- Bulgarians who came to the Balkans from Asia in 681 A.D. and later gave the name of present Bulgaria. They bred horses and made “kumis” from mare’s milk, which was fermented milk. After they settled down on the Balkans, they started breeding sheep and making sour milk from sheep’s milk. Proto-Bulgarians made a variety of  yogurt called “katak”; they curdled fresh sheep milk with fuzzy cheese. The product was prepared in the end of summer when the milk had higher content of dry substance.

Neither of these theories is fully proved.

The Bulgarian  yogurt was mentioned for the first time with this name in the literature of the 7th century. Genghis Khan (1206-1227) used  yogurt in the diet of his army and as a means to preserve meat. Milk was kept in sheep’s stomachs. Under the influence of the micro flora in the stomach, milk-sour fermentation occurred and the result was yogurt. They took out the  yogurt and filled the stomachs again. There was always some  yogurt left inside and the fermentation started again.

In Western Europe the Bulgarian  yogurt was mentioned for the first time in 1664, when an Armenian from Istanbul could cure the French king Luis XI from an incurable then stomach disease feeding him with Bulgarian yogurt. The grateful Luis spread around Europe the information about the cure. Thus modern European  yogurt came from the Bulgarian yogurt.

Micro flora


The micro flora of the Bulgarian  yogurt consists of Lactobacillus bulgaricus  and  Streptococcus thermophilus.

Lactobacillus bulgaricus refers to homofermentative lactobacilli. Bacteria cells are like rods and are under 2 mkm (micrometer) wide. Lactobacillus bulgaricus  grows at 45о C, even at 50-53о C. It does not grow at 15о C. The optimal growth temperature is 40-43о C. Any change in the composition of medium and temperature of cultivation causes changes in the morphological and physiological features of the species.

The other component of micro flora in the Bulgarian  yogurt is Streptococcus thermophilus. Bacteria cells are spherical or oval with a diameter of 0.7 – 0.9 мкм. They are situated in pairs in short and long chains. The optimal growth temperature is between 40 and 45о C. Streptococcus thermophilus grows at 50о C, too but not at 53о C. It does not grow under 20о C.

The two bacteria come from plants. It is considered that due to the contact of animals with plants during grazing, bacteria stick to the udder of the animal and during milking they get into the milk. Thus it is possible to make yogurt.

Under the influence of Lactobacillus bulgaricus  and Streptococcus thermophilus in yogurt, changes in milk sugar, protein substances and milk fat occur and its taste and aroma are formed.

Composition; nutritional, dietary and healing properties

During lactic fermentation the micro flora of the Bulgarian  yogurt causes deep changes in milk composition. Metabolites received have a favorable influence on a number of healthy effects on the human body.



The chemical composition of  yogurt and the changes occurring under the influence of lactic bacteria define its nutritional value. In composition  yogurt is similar to fresh milk but it is also different in many ways. The chemical composition of different kinds of  yogurt is defined by the kind of fresh milk, the animal breed and by the animal diet; by technology applied, etc.


Nutritional value

The nutritional value of  yogurt is defined by the contents of nutritional substances and by the possibility for those ingredients to be used by the human body.  yogurt has a higher nutritional value than fresh milk. The reason is in the changes under the influence of Lactobacillus bulgaricus and Streptococcus thermophilus. The content of milk sugar in  yogurt decreases by 20-30%. The remaining quantity of milk sugar serves as a source of energy equal to 4.1 kilocalories.  yogurt is a rich source of calcium to meet the needs of the human body as calcium maintains the excitability of the heart muscle. Calcium is of great importance for the proper functioning of the nervous system; it stimulates the functioning of endocrine glands and accelerates blood clotting.  yogurt is an essential source of calcium for people who suffer from lactose intolerance and for middle-aged women who often suffer from bone deformation due to insufficient calcium.

Suppressing and energizing properties

Lactobacillus bulgaricus and Streptococcus thermophilus not only increase the nutritional and biological values of  yogurt but they also give it healing properties.   yogurt contains substances which suppress the development of a number of pathogen and non-pathogen microorganisms. It is established that  yogurt micro flora synthesizes antibiotic and antimicrobial substances which suppress the microorganisms in the intestinal tract, especially saprogenic microorganisms.   yogurt is a powerful means to fight some food poisoning; it also has anti fatigue effect and energizes the body.  yogurt helps fight stomach and intestinal cancer and its regular consumption reduces the risk of cancer.

Dietary and healing properties

There is an increasing interest in the relationship between food, cholesterol and cardiovascular diseases. Most desirable foods are those which decrease the high content of cholesterol in the blood serum. The regular consumption of  yogurt considerably reduces cholesterol in the blood serum. Usually, cholesterol is considerably lowered within seven days after you start taking yogurt.  yogurt is a valuable food supplement for people with diabetes; it should be with a reduced fat content so that it provides a better toleration of carbohydrates. This means that  yogurt for people with diabetes should be prepared from skim milk.

If you take antibiotics orally, the biological intestinal balance is upset. As a result, severe intestinal diseases are caused. If you take  yogurt regularly, this affects extremely favorably the recovery of the biological balance of intestinal micro flora. Regular consumption of  yogurt helps create and maintain non-specific immunological reactions in the human body. It is particularly important in the case when you take sterile foods, which is related to the occurrence of viral diseases, especially hepatitis. On the whole,  yogurt has an immunostimulatory effect; it is an effective means against diarrhea and other gastrointestinal diseases.  yogurt helps against headache and is very effective against hangover. Thanks to all these healing properties, the Bulgarian  yogurt contributes to slower aging of the body.


 Yogurt as food for infants

The favorable influence of  yogurt on the development of the child’s body is due to its easier digestion, to better use of protein, calcium and iron, and because of its healing and restorative properties.

Use of  yogurt for animals


 yogurt is used in livestock breeding; it is a very effective means to cure gastrointestinal disorders and diseases in animals. If you add  yogurt to the animal food, their immune system and health will be considerably improved. That means improving the quality of animal meat and products and increasing animal growth.

Which is Bulgarian  yogurt and which is not?

The Bulgarian  yogurt and strains of Lactobacillus bulgaricus are products patented in the Patent Office of the Republic of Bulgaria. Their production is realized under the Bulgarian standard 12-82 Bulgarian yogurt.

General requirements:

According to the Bulgarian standard 12-82, the Bulgarian  yogurt is produced only from two ingredients: milk and yeast. Products which contain other ingredients, like dry milk, soy, starch, and preservatives to stop fermentation, are not Bulgarian yogurt. Yogurt, which meets the requirements of the Bulgarian standard 12-82, has the respective inscription on the packaging. Yogurt, produced by DANONE, for example, is not Bulgarian  yogurt within the meaning of the Bulgarian standard 12-82.

The traditional Bulgarian  yogurt is a unique product due to the unique microclimateе of Bulgaria as experts from the Research Center in the LB Bulgaricum affirm. The LB Bulgaricum is the Bulgarian state company which is authorized to export the know-how of yogurt. The Bulgarian  yogurt has a specific taste and properties. It is sour and thick so when you turn the pail upside down,  yogurt does not fall down, it stays in the pail. Тhe LB Bulgaricum possesses a unique collection of over 700 strains of Lactobacillus bulgaricus, and that enables the company to produce various starter cultures of  yogurt and to achieve various aromas and thickness. In the last thirty years the Company has sold the know-how to over twenty countries including Japan, Germany, Switzerland, Holland, France, the Philippines and Austria.

Lactobacillus bulgaricus can develop only in Bulgaria. Everywhere else it mutates. This is according to the research of Mr. George Georgiev, manager in the Lactina Company which deals in research and production of healthy foods. Mr. Georgiev’s team discovered strains of Lactobacillus bulgaricus in the soil, in the bark of some trees, and even in termite-hills in some of Bulgaria’s regions where the nature is the purest, for example, the village of Momchilovtzi in the Southern Rhodopes. Experiments showed that if you leave a wooden stick in a termite-hill, and then you dip the stick in boiled and cooled milk, it will ferment and turn into yogurt; the same will happen if you dip antique silver coins in the milk.

In the end of their study, Mr. Georgiev’s team concludes, “This will be the food of the new generation. The world is absolutely crazy about healthy food”.