Effects of using composite flour containing wheat flour with different levels of green banana pulp flour on the quality of saj flatbread

Abstract

There is an increasing trend in formulating food to contain dietary fibers and particularly resistant starch. Saj bread (a type of flatbread baked on a plate placed directly on fire) is a potential candidate to act as a vehicle for delivering resistant starch. This study aimed to investigate the effects of using composite flour containing wheat flour substituted with different levels (0, 5, 10, 15, and 20%) of green banana pulp flour "GBPF" on some physicochemical properties of flour (moisture, ash, wet and dry gluten content, gluten index, falling number, and farinograph parameters)  and the quality of saj bread as measured by CIELAB color space, texture (stretchability and texture profile analysis "TPA"), and sensory properties. The texture of the saj bread was monitored during three days of storage. Composite flour moisture content and falling number were unaffected by wheat flour substitution with GBPF, while dry gluten content decreased significantly for composite flour containing 15% or more GBPF. With increasing wheat flour substitution level with GBPF, dough stability decreased. For saj bread color, the L* and b* values decreased with increasing substitution levels, while a* and ∆E*ab values increased. With increasing substitution levels, the stretchability of bread decreased, and all tested TPA parameters increased. With increasing saj bread storage time, the stretchability of bread decreased, and all TPA parameters increased except cohesiveness which decreased. Using composite flour improved bread taste and odor scores and decreased color acceptability scores. Texture and overall acceptability scores were not affected. In conclusion, GBPF can potentially substitute up to 20% wheat flour without negatively affecting saj bread quality.