Submitted to: Applied and Environmental Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/13/2002
Publication Date: 6/1/2002
Citation: Barrangou, R., Yoon, S., Breidt, F., Fleming, H.P., Klaenhammer, T.R. 2002. Identification and characterization of Leuconostoc fallax strains isolated from an industrial sauerkraut fermentation. Applied and Environmental Microbiology. 68 (6):2877-2884. Interpretive Summary: Sauerkraut is a highly nutritious food derived from allowing sliced and salted cabbage to ferment. The quality and uniformity of sauerkraut is highly dependent on the types of bacteria that cause the fermentation. It is desired that certain types of lactic acid bacteria ferment the cabbage sugars to lactic acid and other flavorful compounds. In this research we isolated, identified, and characterized lactic acid bacteria from a commercial sauerkraut fermentation. The diversity of species and strains of bacteria involved in the fermentation was more complex than has been recognized. The long term goal of this research is to better control the sauerkraut fermentation by adding selected cultures of bacteria and controlling environmental conditions to favor their predominance.
Technical Abstract: Lactic acid bacteria strains were isolated from brines sampled after seven days of an industrial sauerkraut fermentation, and six strains were selected for susceptibility to bacteriophage. Bacterial growth in cabbage juice was monitored and fermentation end products identified, quantified, and compared to those of Leuconostoc mesenteroides. Identification by biochemical fingerprinting, endonuclease digestion of the 16S-23S intergenic transcribed spacer (ITS) region, and sequencing the two variable regions V1 and V2 of the 16S rRNA gene, indicated that the six selected sauerkraut isolates were Leuconostoc fallax strains. Random amplification of polymorphic DNA (RAPD) fingerprints indicated that the strains were distinct from one another. Growth and fermentation patterns of the L. fallax isolates were highly similar to those of L. mesenteroides. The final pH of cabbage juice fermentation was 3.6 and the main fermentation end products were lactic acid, acetic acid, and mannitol for both species. However, none of the L. fallax strains exhibited the malolactic reaction, which is characteristic of most L. mesenteroides strains. These results indicated that, in addition to L. mesenteroides, a variety of L. fallax strains may be present in the hetero-fermentative stage of sauerkraut fermentation. The microbial ecology of sauerkraut fermentation appears to be more complex than previously indicated and the prevalence and roles of L. fallax require further investigation.