Bulgarian yoghurt is unique, worldwide famous fermented milk product. Since the antiquity it has been considered a food that sustains the human health and life longevity.
Prof. Iliya Mechnikov, who first investigated the biological qualities of Bulgarian yoghurt, postulated that the process of decay of proteins caused by bacteria in the intestine, leads to the formation of biogenic amines, which are injurious to the human health. Mеchnikov concluded that the influence of unhealthy bacteria might be suppressed by colonization of the human gastrointestinal system with bacteria producing lactic acid. This hypothesis aroused scientific interest worldwide and inspired extensive research on the qualities of Bulgarian yoghurt.
At present, almost 100 years after the appearance of Mechnikov’s hypothesis and the discovery of Dr. Stamen Grigoroff, we are witnessing the process of scientific revelation of the biological value of Bulgarian yoghurt. Application of contemporary molecular, biochemical and genomic approaches revolutionized the understanding the biological nature of this fermented milk product.
Bulgarian yoghurt characteristically contains high number of live beneficial lactic acid bacteria, which counts vary between 400x106 and 1x109 per gram yoghurt. These bacteria cause profound changes in the milk content and synthesize substances which positively influence the human organism.
After ingestion, the yoghurt enters the stomach where the microorganisms are exposed to the stressing influence of the hydrochloric acid and pepsin if the gastric juice. The high protein content of the milk acts as a buffer and prevents the yoghurt microorganisms from the impact of hydrochloric acid. Furthermore, L. bulgaricus and S. thermophilus are resistant to acids and consequently significant portion of the bacteria pass to the lower divisions of the gastrointestinal tract. The uptake of large amounts of beneficial lactic acid bacteria has a strong influence on the intestinal microflora. Many of the pathogenic microorganisms in the intestine are not able to adhere and therefore are excreted from the human organism. Additionally, consumption of Bulgarian yoghurt changes the environment in the intestine in a way that it suppresses the development of pathogenic microorganisms and stimulates the synthesis of mucins, which enhances the physical resistance of the intestine.
Bulgarian yoghurt also stimulates the immune system of the entire human body. It leads to increase of the amount of lymphocytes, killer cells, cytokines and enhanced synthesis of gamma-interferon, which blocks the multiplication of viruses.
After 5-6 hours stay in the small intestine, the yoghurt enters the large intestine. The colon is the bioreactor of human body and its microflora consists of more than 500 microbial species. Studies conducted in France demonstrated that humans consumers of yoghurt are less endangered to colon cancer. Substances with anticancer activity are biosynthesized by the yoghurt bacteria in the course of the lactic acid fermentation.
Bulgarian yoghurt is irreplaceable source of biologically accessible calcium for the human organism. It is estimated that yoghurt delivers 75 % of the calcium needed daily by the population of Western Europe and North America. The calcium contained in yoghurt binds the bile acids and prevents the mucose membrane from irritation. Low pH of the milk ionizes the calcium. Ca2+ ions bind to a specific milk protein – calmodulin – and in this way calcium is absorbed in the intestine. Moreover, the calcium in Bulgarian yoghurt protects the human organism from intestinal diseases. Together with the specific action of L. bulgaricus and S. thermophilus the high calcium concentration in yoghurt promotes the establishment of an intestinal environment which inhibits the pathogenic microorganisms.
Bulgarian yoghurt contains large amounts of live and metabolically active cells L. bulgaricus and S. thermophilus. These lactic acid bacteria degrade about 30 % of the lactose during the fermentation which facilitates the lactose assimilation. In addition, the lactose facilitates the absorption of calcium in the intestine. Experiments indicate that Bulgarian yoghurt is much more efficient remedy for lactose digestion deficiency than fermented milks containing Bifidobacteriae and L. acidophilus. There is a tight correlation between the amount of biologically accessible calcium taken up with the food and the blood pressure. Therefore consumption of Bulgarian yoghurt is also recommended for individuals suffering form high blood pressure.
Bulgarian yoghurt is useful for healing of diarrhea. In combination with the low pH created by the Bulgarian yoghurt microflora, microbial biosynthesis of antibiotic compounds makes the yoghurt consumption and effective way for treatment of bacterial toxins-driven diarrhea, antibiotic treatment-associated diarrhea and diarrhea caused by lactose intolerance. Therefore the World Health Organization recommends in case of diarrhea fresh milk to be replaced with yoghurt.
Besides its remarkable biological qualities Bulgarian yoghurt possesses a high nutritional value. The lactic acid improves the peristaltic of the duodenum, small and large intestine. Bulgarian yoghurt is easier to digest compare to fresh milk and contains increased concentrations of free amino acids.
Bulgarian yoghurt is a unique and powerful biological tool for strengthening the human health. We are convinced that the production of Bulgarian yoghurt has to be in accordance with high quality standards and under strict hygienic, microbiological and technological control.