The seed coat (hull) of broad bean (Vicia faba) (BBH) is a significant secondary product of processing with a promising nutritional profile. Bean hull has a high fiber content (49%), yet it remains underexploited as an ingredient by the food industry. This study investigated the potential of this secondary product to partially replace wheat flour for the development of high-fiber breads. Bread formulations with a range of supplementation levels (0%, 11%, 21% and 31%) were developed and tested for their nutritional and physical properties. The proximate composition of breads revealed that at 31% replacement, the fiber content was 19.19 g/100 g bread, which was significantly higher (p < 0.05) than control breads (3.62 g/100 g bread). The physical (specific volume, density and color) and textural properties of breads were affected by the addition of bean hull. Specific volume and hardness of breads were significantly reduced at ≥21% replacement compared to the control, which may reduce acceptability of the product by some consumer groups. Enzyme-linked immunosorbent assay (ELISA) showed that the gluten content of breads was significantly reduced with bean hull addition (62% depletion for 31% replacement). At 11%, 21% and 31% replacement, one portion (80 g of bread) contains 6.8 g, 11.6 g and 15.3 g of dietary fiber, respectively, which contributes 23%, 38% and 51% of the recommended daily fiber intake (30 g/day). In conclusion, bean hull can be a valuable source of dietary fiber in bread formulations. The study showed BBH could be used to replace up to 21% of the wheat flour without significantly impacting on bread texture and volume.
Bibliographical noteAuthor Contributions: Conceptualization, V. Ranawana and V. Raikos.; methodology, Q.Q. Ni, H.E. Hayes, N.J. Hayward. and D. Stead.; formal analysis, Q.Q. Ni; writing—original draft preparation, Q.Q. Ni and V. Raikos; writing—review and editing, all authors; visualization, Q.Q. Ni.; supervision, V. Raikos; project administration, Q.Q. Ni. All authors have read and agreed to the published version of the manuscript.
Funding: This work is part of the Strategic Research Programme 2016-2021 and is funded by the Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS).
Acknowledgments: Microscopy was performed in the Microscopy and Histology Core Facility at the University of Aberdeen.
Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
- broad bean hull
- Vicia faba
- high fiber
- Broad bean hull
- High fiber
- PHYSICOCHEMICAL PROPERTIES
- DIETARY FIBER
- SENSORY PROPERTIES
- DOUGH RHEOLOGY