What is LAB? Lactic acid bacteria (LAB) are a group of Gram-positive bacteria that are cocci or rod-shaped, non-respiring, and do not form spores. They use carbohydrates as the primary carbon source and ferment them to produce lactic acid. Why use LAB? LAB goes into a pathogenic environment like a first aid emergency worker cleaning up. … Continue reading What is LAB? How To Make And Use It.