Lactobacillus perolens sp. nov., a soft drink spoilage bacterium

Lactic acid bacteria that are able to spoil soft drinks with low pH comprise a limited number of acidotolerant or acidophilic species of the genera Lactobacillus, Leuconostoc and Weissella. Various Gram-positive rods causing turbidity and off-flavour were isolated from orange lemonades. Physiological and biochemical studies including SDS-PAGE whole-cell protein analysis showed a homogeneous group of organisms. The 16S rRNA gene sequence analysis of two representatives revealed that they formed a phylogenetically distinct line within the genus Lactobacillus. All strains were facultatively heterofermentative, producing L-lactic acid. Based on the data presented a new species L. perolens is proposed. The name refers to the off-flavour caused by high amounts of diacetyl. The type strain of L. perolens is DSM 12744 (LMG 18936). A rRNA targeted oligonucleotide probe was designed that allows a fast and reliable identification of L. perolens.