• The soy sauce yeast strains could accumulate more trehalose under salt and heat shock. But the optimal salt stimulate concentration was different.
• Optimal condition for growth and trehalose productivity of Zygosaccharomyces rouxii (S) and Torulopsis versatilis (T) is corn juice 13 Brix in 9% salt while the mutants(S3-2, S3-5 ) in 12% salt.
• Optimal temperature at 40°C for 30 mins for the original strains The mutant yeast strains could accumulate less trehalose than the original.
• In general, the mutant yeast strains could accumulate less trehalose than the original, even though S3-2 and T3-5 have a stronger resistance to salt, so a conclusion could be made that trehalose had little relationship with the salt tolerance of the soy sauce yeast strains.