Development and quality evaluation of functional bread fortified with dietary fiber extracts from coconut kernel

Abstract

This study explored the development of functional bread fortified with dietary fiber from Defatted Desiccated Coconut Residue (DDCR), a fiber-rich by-product of virgin coconut oil production. Given the growing interest in sustainable foods, DDCR is a valuable source of soluble and insoluble dietary fiber. The research aimed to isolate dietary fiber from DDCR and evaluate the quality, nutritional value, and sensory acceptability of bread formulations fortified with it. Dietary fiber extracted from DDCR was analyzed for quality parameters, including free fatty acid content, peroxide value and water absorption capacity. Bread samples were made by partially replacing wheat flour with DDCR dietary fiber at levels of 2.5%, 5% and 10%, and were evaluated against a control (100% wheat flour) for proximate composition, physical properties and sensory attributes. DDCR dietary fiber showed low free fatty acid (0.43 ± 0.02) and peroxide value (1.92 ± 0.09), high total dietary fiber (80.11 ± 1.36) and significantly higher water absorption capacity (693.26 ± 16.66) compared to wheat flour (94.60 ± 29.30). Bread with 2.5% dietary fiber had significantly higher moisture (39.8 ± 2.66), fat (2.05 ± 0.46) and crude fiber (0.82 ± 0.15) than the control. Sensory scores for taste (3.75 ± 1.01), texture (3.68 ± 0.78) and overall acceptability (3.84 ± 0.62) were significantly higher in the 2.5 % dietary fiber-fortified bread compared to the control and other dietary fiber-incorporated breads. The textural properties and baking characteristics of this bread were not significantly different from the control. In conclusion, 2.5% DDCR dietary fiber is a promising ingredient for enhancing bread nutrition while maintaining consumer acceptability.