Reduction in the ammonia content of salmon shark meat by a fermented rice bran suspension with the Satoumi-sourced yeast Saccharomyces cerevisiae Misaki-1 and lactic acid bacteria Lactobacillus plantarum Sanriku-SU8

• Ammonia-lowering capacity of yeast and LAB strains were examined.
• Ammonia was reduced by a co-culture of S. cerevisiae Misaki-1 and L. plantarum Sanriku-SU8.
• These strains grew well in rice bran (nuka)-aqueous extract suspension (AES).
• This fermented nuka-AES had a good flavour and demonstrated ammonia-lowering capacity.

To reduce the ammonia content in the meat of the shark Lamna ditropis, the ammonia-reducing capacity of soaking solutions containing 10% sucrose and 5% NaCl, with or without selected strains of yeast Saccharomyces cerevisiae Misaki-1 and lactic acid bacteria (LAB) Lactobacillus plantarum Sanriku-SU8 was evaluated. After the 48 h soaking with the yeast and LAB, ammonia content in the meat was reduced to about from 150 to 50 mg/kg. S. cerevisiae Misaki-1 and L. plantarum Sanriku-SU8 grew well in 10% water extract suspension (AES) of rice bran (nuka). The fermented nuka-AES had a good flavour and demonstrated the ability to reduce the ammonia content of meat from about 290 to 100 mg/kg. These results suggest that soaking treatment with S. cerevisiae Misaki-1 and L. plantarum Sanriku-SU8 can reduce improve salmon shark meat flavour.