Lactic acid bacteria (LAB) are key for the fermentation of sourdoughs to improve the quality and nutritive value of bread. The aim of this study was to isolate the LAB starter for sourdough fermentation from -, a Korean traditional rice cake. Among the twenty two LAB screened, five isolates were selected based on exo-polysaccharide production. Among them, three isolates showed cell growth greater than 8.5 Log CFU/g, maximum increase in the volume of dough, and dextran concentration up to 0.16%. During the sourdough fermentation, pH and total titratable acidity (TTA) were changed, as the three isolates synthesized lactic acid and acetic acid with fermentation quotients less than 2.0. They were identified as EFEL005, EFEL004, and EFEL006. They displayed good fermentation properties (growth, dextran production, pH, and TTA) in dough and they are regarded as potential starters to be used in sourdough fermentation.

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Jeung-pyun, a fermented rice cake, is prepared by fermenting rice sourdough using makgeolli, a traditional Korean rice wine, in the presence of yeast and lactic acid bacteria (LAB). The goal of this study was to conduct biochemical and microbial analyses of five different rice sourdoughs, each fermented with a different commercial makgeolli, using culture-dependent and culture-independent approaches. All sourdough samples fermented with different makgeolli for 6.5 h showed different profiles in pH, total titratable acidity, organic acid concentration, and microbial growth. LAB belonging to different genera were identified based on colony morphology on modified MRS and sourdough bacteria agar medium. PCR-denaturinggradient gel electrophoresis analyses of the five sourdoughs showed different bands corresponding to LAB and yeast. 16S/26S rRNA gene sequence analyses of the samples confirmed that the predominant LAB in the five fermented rice doughs was ,, and . Various other spp. and were common in all five fermented samples. This study provides comprehensive and comparative information on the microflora involved in fermentation of rice sourdough and signifies the need to develop effective starters to enrich the quality of jeung-pyun.

The major lactic acid bacteria (LAB) strains in cabbage-kimchi and their origins were investigated by single component omission analysis. Cabbage-kimchi samples were prepared by omitting each of the ingredients (garlic, ginger, chive, red pepper, and fish sauce), and microbial dynamics were monitored during fermentation. Fingerprinting analysis, using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE), and sequencing of the PCR products, revealed that Leuconostoc citreum, Weissella cibaria, W. confusa, and Lactococcus lactis were the predominant species present in kimchi after 3 days of fermentation. Of these, Leuconostoc sp. and Weissella sp. were mainly derived from garlic. Similar analyses confirmed the presence of Leuconostoc spp., Weissella sp., and Lactobacillus sp. in various garlic products (mainly peeled garlic). These results demonstrate that garlic is an important constituent among raw ingredients since it provides LAB for the early stages of cabbage-kimchi fermentation.