Lactobacillus delbrueckii subspecies bulgaricus скачать в хорошем качестве

Lactobacillus delbrueckii subspecies bulgaricus

A gram-positive long rod. It is non-motile, filamentous, anaerobic, and non-pathogenic and does not form spores. It is aciduric or acidophilic, since it grows effectively in a low pH 4.6-5.4 and temperatures 40-44 °C under anaerobic conditions. It is a homofermentative lactic acid bacterium due to lactic acid being the single end product of its carbohydrate digestion, considered a probiotic. It is the main bacterium used for the production of yogurt and that functions in the ripening of some cheeses and in other naturally fermented products. It is commonly used alongside Streptococcus thermophilus as a starter for making yogurt, working in synergy (symbiotic relationship), producing amino acids from milk proteins, which are then used by S. thermophilus. Both species produce lactic acid, which gives yogurt its tart flavor and acts as a preservative. The resulting decrease in pH also partially coagulates the milk proteins, such as casein, resulting in yogurt's thickness. While fermenting milk, it produces acetaldehyde, one of the main yogurt aroma components. Some strains such as L. bulgaricus GLB44, also produce bacteriocins, which have been shown to kill undesired bacteria in vitro. It has also been considered a contaminant of beer due to its homofermentative production of lactic acid, an off-flavor in many styles of beer. In other styles of beer, however, lactic acid bacteria can contribute to the overall appearance, aroma, taste, and/or mouthfeel, and generally produce an otherwise pleasing sourness.