1991 Volume 38 Issue 8 Pages 663-667
The utilization of soya lactic acid bacteria (Pediococcus halophilus) was investigated to improve the quality and color of Shiro-shoyu (extremely light colored soy sauce). The color-lightening strains lowered the oxidation-reduction potentials of Shiro-shoyu moromijuice (MJ) medium during their growth and suppressed the browning of the medium. A color-lightening strain C-6-8 grew vigorously (viable cell of 108 per ml) in the Shiro-shoyu MJ medium. In the incubation at 21-30°C, the growth of strain C-6-8 slowed down with lowering temperature, while at the lower temperature the period of fermentation were longer than that at the higher temperature. In Shiro-shoyu moromi (mash) inoculated with strain C-6-8, lactic acid fermentation was continued about two weeks at 22°C, and darkening phenomenon of moromi was suppressed during the fermentation. The contents of total nitrogen and L-glutamic acid of Shiro-shoyu made by inoculation of strain C-6-8 were slightly lower than that of non inoculated. However, production of a large quantity of lactic acid and acetic acid resulted low pH and high buffer action. These results suggested that the inoculation of soya lactic acid bacteria to Shiro-shoyu moromi were useful to improve the taste and color of Shiro-shoyu.
