Comparison of nutritional composition, HPLC characterization, antioxidants property and starch profile of Sphenostylis stenocarpa composite bread and wheat bread

Background & Aim: The use of composite flour and combined additives in wheat flour to improve their nutritional and health benefits have increased. This study focuses on the examination and comparison of the phenolic characterization, antioxidant properties, mineral content, starch profile, in vitro starch digestibility and in vitro α-amylase inhibition present in produced composite bread and wheat bread. Experimental: Sphenostylis stenocarpa flour (SSF) and combined additives (dry gluten powder, fungal α-amylase and sodium stearoyl-2-lactylate) were incorporated into wheat flour to produce composite SSF bread. Wheat flour bread was prepared as a control. Results: The HPLC result showed higher values of gallic acid (1806.68 µg/100 g), p-coumaric acid (104.49 µg/100 g) and quercetin (22054.67 µg/100 g) in SSF bread while sinapic acid (195.88 µg/100 g), caffeic acid (1372.90 µg/100 g), ferulic acid (535.79 µg/100 g) were higher in control bread. Ferric-reducing antioxidant properties and mineral contents (Zinc, Ca, Fe, K, Mg, Mn and copper) were higher in SSF in comparison to control bread (P<0.05). The SSF bread had higher resistant starch and slowly digestible starch values but decreased total starch and rapidly digestible starch values. The in vitro starch digestibility (IVSD) value was also 0.54 times lower in SSF compared to control bread. The α-amylase inhibitory potential of SSF bread (56.77%) was significantly higher (P<0.05) in comparison to control bread (29.96%). It could be concluded that the incorporation of Sphenostylis stenocarpa in baked products such as bread will be of high nutritional benefits to humans. Recommended applications/industries: Sphenostylis stenocarpa is an underutilized bean that is rich in minerals, antioxidant properties and slow starch digestion potency which can be explored to prevent or manage the pathologic conditions that are related to sugar metabolisms. The utilization of underutilized Sphenostylis stenocarpa will go a long way in combating food insecurity