Production and development of this truly incredible yogurt starter

Bacillus Bulgaricus is truly incredible.

This yogurt starter culture consists of two strains – lactobacillus bulgaricus and streptococcus thermophiles in a perfect combination to make the most incredible yogurt. Every single time.

The lactic acid bacteria we use are isolated from natural sources in Bulgaria and selected according to the microbiological, physiological and metabolic characteristics, which are beneficial for the human health. The lactic acid bacteria are famous for their role as major biological regulators of the gastrointestinal tract.

The combination of Lactobacillus delbrueckii ssp. bulgaricus strains that we use exhibit unique healthy effects: strengthening and stimulation of the immune system, regeneration of the beneficial microflora, improving and normalization of the physiological processes in the gastro-intestinal tract.

Our starter cultures

We produce yogurt starter cultures for the dairy industry and end-user utilization.

For this, our scientists executed a large scale program for isolation of unique strains of lactic acid bacteria from natural sources in ecologically preserved areas in Bulgaria – Rila, Pirin, Rhodope Mountains and the Balkans chain. This isolation project laid the foundation for the creation of a collection containing diverse frozen and freeze-dried strains of different of bacterial species, which is continuously enriched with new isolates.

Our cultures are patented and deposited in the National Bank for Industrial Microorganisms and Cell Cultures, Sofia, Bulgaria (NBIMCC).

The advantages of our starter cultures are:

  • formation of traditional taste, aroma and texture of the yogurt
  • original cultures with proven identity and symbiotic cultures for yogurt production
  • free of genetically manipulated microorganisms
  • selected set of multistrain phage-resistant starter cultures with participation of four strains Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophiles
  • focus on the elaboration of starter cultures based on local lactic acid bacterial strains with proven geographic identity from Bulgaria and Balkan peninsula, which are established as stable symbiotic cultures via natural selection through the ages of traditional yogurt production.

Production and facilities

Our production facilities are located in the vicinity of Lyulin mountain near Sofia, Bulgaria.

We have a small team of professionals looking after the quality of our starters, every step of the way. The production of our yogurt starter goes thru the following stages.

  • Preparation — at this step we prepare the bacteria and the liquid nutrient medium for the development of microorganisms
  • Fermentation — this is a complex step during which the already grown bacteria are sterilized, the different strains are mixed together (inoculated and enriched), and then left for the naturally occurring fermentation processes to develop
  • Pelletization — at this step the many newly formed colonies of bacteria clump together and form groups that look like small pellets
  • Lyophilization — this is the step when we cool and dry the bacteria
  • Grinding, mixing and packing — in the final stage the finished dry matter is ground, if necessary, mixed and packaged in the very same packs you get.

Here is a sneak peek of the production process.

Research and development

We also do a great deal of research and development in order to be able to produce the excellent product that Bacillus Bulgaricus is. We used the following two sources of isolation for our lactic acid bacteria collection:

  • Natural sources – fresh milk, whey, plants and herbs, spice plants etc.
  • Homemade yogurt and other fermented milk products prepared without application of industrial starters

The lactic acid bacterial strains are isolated and characterized according to the requirements of the International Dairy Federation (IDF) and International Dairy Foods Association (IDFA) standards and Bergey’s Manual.

We maintain our VERY OWN collection of strains, isolated from natural sources in ecologically preserved areas in Bulgaria. Our collection consists of strains from three groups:

І. group – thermophilic homofermentative lactobacilli

  • Lactobacillus delbrueckii ssp. bulgaricus
  • Lactobacillus acidophilus
  • Lactobacillus helveticus
  • Lactobacillus lactis

ІІ. group – thermophilic lactic acid streptococci

  • Streptococcus thermophiles

IIІ. group – mesophilic lactococci and lactobacilli

  • Lactococcus lactis
  • Lactococcus lactis biovar diacetylactis
  • Lactococcus cremoris
  • Leuconostoc mesenteroides ssp. cremoris
  • Lactobacillus casei;
  • Lactobacillus plantarum etc.

Most of the strains from the first two groups are isolated form various natural sources, mainly medicinal plants form ecologically clean high-mountain regions in Bulgaria: Rila, Pirin, Rhodope Mountains and the Balkans. Another part is isolated and selected form traditional home made Bulgarian yogurts form the districts of The Seven Rila Lakes, Skakavitsa, Trun, Pavelsko, etc. The mesophilic lactic acid bacteria form the third group include mainly isolates from raw milk, and homemade dairy products from raw milk, sour whey, forages, etc. After characterization, strains of this group were selected for creation of starter cultures for cheese production, according to their acidification potential during the fermentation, flavor, proteolytic and lipolytic activity in the course of the cheese maturation and storage.

We continuously and actively keep on isolating and characterizing thermophilic lactic acid strains of the Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus bacteria in order to diversify and enrich the natural genetic stock of our collection.

Our ongoing identification program includes a variety of modern biochemical and physiological tests. The main criteria that we apply for estimation of the technological and healthy potential of those bacteria are:yoghur

  • Growth dynamic in artificial nutrition media
  • Acidification potential and dynamic (37-43°C)
  • Spectrophotometric determination of the potential for production of D- and L-Lactic acid by means of enzyme tests
  • Postacidification activity (5°C and 10°C)
  • Organoleptic and texture properties
  • Osmotic tolerance
  • Antibiotic sensitivity
  • Antimicrobial activity
  • In vitro tests for survival in gastric and pancreatic juice
  • In vitro bile salts resistance
  • Flavor and spectrophotometric enzymatic determination of acetaldehyde concentration
  • Spectrophotometric enzymatic determination of lactose degradation and release of glucose and galactose
  • Biochemical identification tests
  • Optimization of bacterial survival during freeze-drying and storage

The uniqueness of our method (and starter)

Traditionally, Bulgarian yogurt is made using starter culture containing two strains — Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. However, many yogurt producers and starter culture makers include Lactobacillus acidophilus and/or Lactobacillus lactis. Our research has shown that this composition harms the quality, taste and flavor of the end products and results in a blander, generic taste of the yogurt.