Enhancing the nutritional profile of de‐oiled rice bran through solid‐state fermentation with <i>Aspergillus oryzae</i>

Abstract An experiment was conducted to explore the impact of fermenting de‐oiled rice bran (DORB) with Aspergillus oryzae on its nutrient composition and anti‐nutritional factors. DORB was inoculated with 7‐day‐old A . oryzae culture grown on potato dextrose agar. The experiment was conducted in triplicate for 120 h, with samples collected at 0, 24, 48, 72, 96, and 120 h. After 72 h of fermentation crude protein, and ether extract content contents increased significantly ( p &lt; 0.05) whereas the nitrogen‐free extract decreased significantly ( p &lt; 0.05). The fermentation of DORB with A . oryzae resulted in an increase in the crude protein content from 14.51% to 18.05% after 72 h of fermentation and then gradually decreased thereafter. The ether extract content peaked at 72 h before decreasing. Fermentation resulted in a significant increase ( p &lt; 0.05) in the crude fiber and total ash content. A significant decrease ( p &lt; 0.05) in the phytate and trypsin inhibitor activity was also observed. Trypsin inhibitor activity decreased by 8.34% after 72 h whereas phytate content decreased by 1.95% after 120 h of fermentation with A . oryzae . The findings of the present study demonstrate that A . oryzae enhances the nutritional quality of DORB by improving nutrient profile and reducing the anti‐nutritional factors.