Abstract:

Different molds, yeasts, bacteria and edible fungi were separately used for the fermentation of okara, and
Pleurotus ostreatus Nongping 1 was screened out. The fermentation conditions were optimized by single factor method
and response surface Box-Behnken design. Considering operational feasibility, the optimal fermentation conditions were
determined as okara initial pH 7.5, inoculum amount of 10.5%, fermentation temperature of 30.5 ℃, and fermentation time
of 13 d. Under these optimal conditions, the content of amino acid nitrogen in dry fermented okara was 3.34%, which was
97.02% as compared to the predicted value, and the content of crude protein was 33.86%, which was 98.98% of the predicted
value. These results showed that the experimental values were in good agreement with those predicted.

Key words: okara, Pleurotus ostreatus Nongping 1, solid-state fermentation, amino acid nitrogen