Comparative Study of Raw and Fermented Oat Bran: Nutritional Composition with Special Reference to Their Structural and Antioxidant Profile

Oat bran has gained significant attention among cereal brans owing to its comparatively higher presence of dietary fibers and phytochemicals. The objective of the current research is to personify the nutritional and functional aspects of oat bran after yeast-induced (Saccharomyces cerevisiae) fermentation. For this purpose, a comparative study of raw and fermented oat bran was conducted to investigate the nutritional profile, antioxidant activity and functional characteristics of oat bran. Furthermore, pre- and post-structural variations on fermented bran were determined through scanning electron microscopy (SEM). The results show that crude fat, protein and total dietary fiber (soluble and insoluble) contents were significantly improved after fermentation. Moreover, the post-fermentation value of soluble dietary fiber was increased from 5.01 +/- 0.21 to 7.2 +/- 0.1%. Antioxidant activity, DPPH-RSA and ferric reducing antioxidant power values of bran samples were also enhanced through fermentation and the anti-nutritional factor, i.e., phytate, was significantly reduced from 1113.3 +/- 8.5 to 283.4 +/- 3.5 mg/100 g in bran samples after fermentation. Furthermore, the surface morphology of fermented oat bran shows scattering and pores, while raw oat bran shows visible aggregation in SEM micrographs. Water-holding capacity was also enhanced up to 2.11 (5.68%) after fermentation. In conclusion, the post-fermentation results revealed that yeast-induced fermentation enhanced the physicochemical, structural and antioxidant characteristics of oat bran.