showed that the levels of peptide with MW less than 1000 Da in
the samples fermented by L. casei Zhang mixed with B. subtilis
natto, L. plantarum P-8 mixed with B. subtilis natto for 24 h
increased 5.0% and 12.9%. The sample fermented by B. animalis 937
mixed with B. subtilis natto decreased 4.6% relative to that of the
control group, because the production of proteases was poor at the
initial stage of the fermentation, the protein of the soybean was