This study was initiated in order to develop a method for soy
sauce fermentation at low salt concentrations without decreasing
quality. First, the physicochemical characteristics and microbial
community in soy sauce fermentation can be adversely affected by
reducing the salt content. However, the application of two indigenous
yeasts, which were isolated at different stages during soy
sauce fermentation, successfully controlled these adverse effects.
Specifically, it was confirmed that addition of T. delbrueckii, a high
ethanol producing strain, effectively inhibited the growth of putrefactive
microbes. Furthermore, combining T. delbrueckii with P.
guilliermondii, a high producing strain for fusel alcohols, resulted in
a balance of more complex and richer flavors with a flavor profile
pattern identical to that of high-salt. Hence, the results will be very
useful for industrial applications, giving a technological option to
manufacture salt-reduced soy sauce that does not give rise to microbial
and physicochemical changes.