Strains Quatro is a probiotic food supplement containing a total of 4.5 billion CFU Bifidobacterium animalis subsp.lactis BB-12, Lactobacillus acidophilus LA-5, Streptecoccus thermophilus STY-31, Lactobacillus delbrueckii subsp. bulgaricus LBY-27 strains in one capsule. All the strains in its content are patented. Bifidobacterium BB-12 and Lactobacillus acidophilus LA-5 are the most documented strains in the world with scientific articles. It is produced by Chr Hansen, one of the companies working on probiotic products. Their stability is guaranteed until the end of their shelf life.