Stamen Grigorov: The Doctor Who Discovered the Secret of Bulgarian Yogurt | Стамен Григоров
Bulgarian yogurt (кисело мляко) is famous around the world, and the reason has a name: Lactobacillus bulgaricus. The bacterium was discovered by a Bulgarian, Dr Stamen Grigorov (1878–1945).
From a village to Geneva
Grigorov was born in the village of Studen Izvor near Tran. He studied natural sciences and medicine in Montpellier and Geneva. In 1905, working in the laboratory of Professor Leon Massol in Geneva, he looked at homemade yogurt from his home region under the microscope.
The discovery
He identified the rod-shaped bacterium responsible for fermenting milk into yogurt. It was later named Lactobacillus bulgaricus (now Lactobacillus delbrueckii subsp. bulgaricus) in honour of Bulgaria. His findings caught the attention of Nobel laureate Ilya Mechnikov at the Pasteur Institute in Paris, who linked Bulgarian yogurt with the long lives of Bulgarian villagers. That idea helped start the global interest in yogurt and probiotics.
More than yogurt
Grigorov also worked on a tuberculosis vaccine based on penicillium fungi, years before penicillin was widely used. He returned to Bulgaria and worked as a doctor in Tran.
His legacy
- The Museum of Yogurt in his native Studen Izvor tells his story
- Every jar labelled “Bulgarian yogurt” carries his discovery
- Japan’s Meiji company has made Bulgarian-style yogurt since the 1970s, and it remains one of the country’s best-known dairy products
More from this series: Famous Bulgarians and their gifts to the world
Top image: AI-generated illustration, not a photograph.
