High Stability Freeze Dried Lactobacillus Bulgaricus

Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus), one of the three subspecies of Lactobacillus delbrueckii, is a facultative anaerobic, non-motile, non-spore-forming rod-shaped lactic acid bacterium. It is considered acid-tolerant or acidophilic because it requires a low pH (about 5.4-4.6) for efficient growth. This bacterium has complex nutritional requirements. In yogurt manufacturing, L. bulgaricus works synergistically with Streptococcus thermophilus as thermophilic starter cultures. At an optimal temperature of about 42ºC, these cultures grow rapidly, acidify quickly, and have the desired organoleptic properties. L. bulgaricus and Streptococcus thermophilus work synergistically, with L. bulgaricus producing amino acids from milk proteins that are then utilized by Streptococcus thermophilus. Both species produce lactic acid, which gives yogurt its sour taste and acts as a preservative. The resulting drop in pH also partially coagulates milk proteins, such as casein, causing the yogurt to thicken. While fermenting milk, L. bulgaricus produces acetaldehyde, one of the main aroma components of yogurt. Some strains of Lactobacillus bulgaricus also produce bacteriocins that have been shown to kill harmful bacteria in vitro. Lactobacillus bulgaricus and Streptococcus thermophilus do not reside in the human gut, but are now considered probiotics because their metabolism produces beneficial components to support the human gastrointestinal tract and they have been used safely for hundreds of years.

 

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