The effect of fermentation without or with lactic acid bacteria and storage time on the phytic acid, in vitro dry matter digestibility, and nutrient contents of rice bran

Abstract

Storage of rice bran (RB) at anaerobic conditions is the potential way to reduce phytic acid (PA) and stabilize the nutrient contents. This study was aimed to examine the effect of fermentation without or with lactic acid bacteria (LAB)) and storage time on the PA, in vitro dry matter digestibility, and nutrient content of RB. A factorial completely randomized design was used in this study. The first factor was the fermentation method, RB with no fermentation (M0), with fermentation without LAB (M1), with fermentation plus LAB (M2). The second factor was storage time, namely 0 (S1), 5 (S2), 10 (S3), and 15 (S4) weeks. Each unit was repeated 4 times. Parameters measured include phytic acid (PA), in vitro dry matter digestibility (IVDMD), crude protein (CP), and crude fiber (CF) contents. A two-way analysis of variance was employed to determine the significant effect of the treatment. For PA the interaction between method and storage time and the main effects were all significant (P < 0.01). For IVDMD, only the fermentation method affected significantly (P < 0.05), with M0 as the lowest and M2 as the highest at all storage time. However, the CP content of RB was not affected significantly (P > 0.05) by treatment. In addition, the CF content of rice bran was not significantly (P > 0.05) affected by an interaction between method and storage time but significantly reduced (P < 0.01) by the method of fermentation. It was concluded that fermentation with the addition of LAB anaerobically decreased anti-nutrient content, increased the feeding and nutritive value of RB.