Rapid, Species-Specific Detection of Lactic Acid Bacteria from Beer Using the Polymerase Chain Reaction. Luke J. DiMichele, Department of Food Science & Technology, University of California, Davis, CA 95616 and Baxter Microscan, West Sacramento, CA 95691, and Michael J. Lewis, Department of Food Science and Technology, University of California, Davis, CA 95616.. J. Am. Soc. Brew. Chem. 51:0063, 1993.

A rapid method for detecting Lactobacillus brevis, L. casei, and L. plantarum from beer was developed using the polymerase chain reaction (PCR). Regions of the 16S rRNA sequences unique to each organism were used to generate species-specific PCR products, which were visualized by gel electrophoresis. Small numbers of these bacteria were isolated from water and beer by membrane filtration and membrane dissolution, before the PCR reaction. This method for detecting spoilage lactic acid bacteria was rapid and sensitive and allowed identification at the species level. However, beer contained a PCR inhibitor that decreased sensitivity.

Keywords: Beer spoilage, Lactic acid bacteria, Membrane filtration, Polymerase chain reaction, 16S rRNA