Leuconostoc mesenteroides and
Lactobacillus sakei are the predominant lactic acid bacterial(LAB)species in
kimoto, the traditional yeast starter for sake brewing. It was reported that the habitat of
L. mesenteroides might be the surrounding equipment in sake breweries, while it might be difficult for
L. sakei to survive over a year in sake breweries after the brewing season. To clarify the cause of the different ecologies, we investigated the stress tolerance of
L. mesenteroides and
L. sakei by exposure to several stresses, namely, heat, drying, and poor nutrition, which are most likely to be experienced by the LAB in sake breweries. The viable cell counts of
L. mesenteroides and
L. sakei strains after exposure to heat and drying stresses were almost identical. However,
L. mesenteroides strains exhibited higher levels of resistance to poor nutrition stress than
L. sakei strains. In addition,
L. sakei strains lost their culturability completely on exposure to poor nutrition stress at 30℃. These results suggest that nutrient-poor conditions at high temperature, which can exist in sake breweries in summer, is a lethal environment not for
L. mesenteroides but for
L. sakei.
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