LACTIC ACID α-hydroxypropionic acid CH3CH(OH)COOH 

Lactic acid is produced industrially by bacterial fermentation of carbohydrates, or by chemical synthesis from acetaldehyde that comes from coal or crude oil. In 2009, lactic acid was produced predominantly (70–90%) by fermentation. Production of racemic lactic acid consisting of a 1:1 mixture of d and l stereoisomers, or of mixtures with up to 99.9% l-lactic acid, is possible by microbial fermentation. Industrial scale production of d-lactic acid by fermentation is possible, but much more challenging. Fermentative production Fermented milk products are obtained industrially by fermentation of milk or whey by Lactobacillius species bacteria: Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus delbrueckii subsp. bulgaricus (Lactobacillus bulgaricus), Lactobacillus helveticus, Lactococcus lactis, and Streptococcus salivarius subsp. thermophilus (Streptococcus thermophilus). As a starting material for industrial production of lactic acid, almost any carbo…