Molecular characterization of Lactobacillus curvatus and Lact. sake isolated from sauerkraut and their application in sausage fermentations

Abstract
Lactobacillus curvatus and Lact. sake are best adapted to meat fermentations and dominate the flora during the whole process. In fermenting sauerkraut, Leuconostoc mesenteroides subsp. mesenteroides is the major organism only during the early phase. In this environment Lact. curvatus and Lact. sake provide up to 50% of the microbial flora especially of the later phase, depending on the process conditions. Strains of Lact. curvatus and Lact. sake isolated from fermenting sauerkraut were identified by hybridization with species specific 23S rRNA-targeted oligonucleotide probes and further characterized. In 59 of 72 strains, plasmid DNA was detected. Small cryptic plasmids of 20 strains were found to be homologous with pLc2, a 2.6 kb plasmid from Lact. curvatus LTH683, which was originally isolated from meat. The ability to compete was investigated in fermenting sausages of two strains each of Lact. curvatus and Lact. sake isolated from sauerkraut. One strain each of Lact. curvatus and Lact. sake was found to outnumber the meat-borne flora and govern the process.