Heterofermentative lactic acid bacteria as a starter culture to control kimchi fermentation

- The most important characteristics using heterofermentative LAB as a starter were determined.
- Bacteriocin-enhancing characteristics are crucial for a starter culture.
- Production of favorable metabolic products is associated with high sensory characteristics.
- Leu. citreum GR1 turned out to have optimal properties for a starter culture.

Among 171 lactic acid bacteria (LAB) strains isolated from kimchi, the following three were selected: Leuconostoc citreum GR1, which has bacteriocin-enhancing activity, L. citreum C2, which produces mannitol but has no bacteriocin-enhancing activity, and Pediococcus pentosaceus MP1, which has the highest and broadest antibacterial activities. Selected LAB strains were independently introduced in the kimchi fermentation process to investigate the effects of the starter culture on kimchi fermentation. L. citreum GR1 and P. pentosaceus MP1 were predominant in kimchi during the fermentation process (60 days). Kimchi fermented using L. citreum GR1 had a high sensory quality and an extended shelf-life, whereas that fermented using P. pentosaceus MP1 had no significant improvement in the sensory quality. L. citreum C2 was predominant for 6 days only; thus the characteristics of kimchi fermented using L. citreum C2 were similar to those of kimchi fermented without starter culture. Controlling kimchi fermentation using heterofermentative LAB as a kimchi starter culture is difficult. However, this study revealed that controlling kimchi fermentation using heterofermentative LAB is possible. Therefore, the most important microbial characteristics of heterofermentative LAB as a starter culture was their bacteriocin-enhanced activities. Production of favorable metabolic products is required to obtain high sensory characteristics of kimchi.