Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus: A Review
Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus are thermophilic lactic acid bacteria of particular interest to the dairy industry. For the protosymbiotic relationship that exists between strains of these bacteria, they are largely used in association as starter cultures for the production of several fermented foods. Due to their commercial significance, many basic and applied research has led to an increasing understanding of the essential characteristics and technological properties of strains belonging to these species. This review deals with some recent knowledge on taxonomy, metabolic and genetic characteristics of S. thermophilus and L. delbrueckii subsp. bulgaricus. The antagonistic activity and bacteriophage resistance of these species are also discussed.