Evaluation of fermented African yam bean flour composition and influence of substitution levels on properties of wheat bread

Abstract

The composition (proximate, amino acids, in vitro protein digestibility [IVPD]), antinutritional factors (ANFs), functional properties, and antioxidant activity of fermented African yam bean flour (FAYBF) were determined in this study, and the effect of substituting FAYBF on the properties (nutritional, physical, and functional) of bread was investigated. Fermentation significantly (P ≤ 0.05) increased the levels of nutrients,IVPD,total phenolic content (TPC),and antioxidant activity in the flour, with significant (P ≤ 0.05) reduction in ANFs. The water absorption capacity (WAC) and oil absorption capacity (OAC), and swelling capacity of the flour increased after fermentation, while bulk density decreased. Substitution of wheat flour with FAYBF increased WAC and OAC, while peak viscosity decreased. Composite breads had higher nutritional, IVPD, TPC, and antioxidant activity than 100% wheat bread. The study demonstrates that FAYBF could be explored for the preparation of wheat-based bread, with reduced gluten levels.

Fermentation of Cereals and Legumes: Impact on Nutritional Constituents and Nutrient Bioavailability

“…It was postulated that the increase in the level of protein was due to the fungi utilizing lipids and starch as well as the ability of these fungi species to produce proteins [11,143]. An increase in the protein (3-25%) through the SSF of legume flours has also been previously reported [144][145][146][147][148][149], with these studies ascribing such increases to the synthesis of new proteins during fermentation, yeast proliferation, the loss of dry matter, net synthesis of protein by fermenting seeds, increase in fungal biomass that was produced from the fermenting microorganism and partial protein denaturation and pH decrease during fermentation. The mechanism of an increase in the protein content of lupin flours fermented with Aspergillus ficuum, Aspergillus sojae and their co-cultures could be linked to the microorganisms using the substrate as carbon and energy sources during SSF to produce fungal protein [150].…”

“…The mechanism of an increase in the protein content of lupin flours fermented with Aspergillus ficuum, Aspergillus sojae and their co-cultures could be linked to the microorganisms using the substrate as carbon and energy sources during SSF to produce fungal protein [150]. The formation of soluble products and monomers after fermentation, as well as the interconversion of AAs, was reported to have also enhanced AA levels by up to 13%, though an AA decrease of between 0.3% and 16% was equally reported during the fermentation of African yam bean flour [149]. The increase in AAs might also be attributed to transamination or synthesis taking place during the SSF process [11,143].…”

“…A 3% decrease in the carbohydrate content reported during the fermentation of red bean (Phaseolus angularis) was attributed to the use of carbohydrate as the energy source for fungal growth [148]. Different authors [130,144,146,149,153,178,190,191] have all equally reported reductions in carbohydrate levels during the fermentation of African oil bean (7%), tempeh (0.7%), cowpea (3%), mahogany bean (up to 61%), kidney bean (17%), lentil (6%), African yam bean (4%) and Lyon bean (up to 26%), and ascribing such reductions to the use of carbohydrate-related compounds as the energy source by fermenting microorganisms for growth and metabolism as well as the conversion of oligosaccharides to simple sugars. The observed varying decreases in the carbohydrate values of these legumes could be due to differences in the inherent composition (e.g., amylose, amylopectin and the structural composition of carbohydrates), plant varieties, species as well as fermenting microorganisms present during the fermentation process.…”

Antioxidant Potential, Antinutrients, Mineral Composition and FTIR Spectra of Legumes Fermented with Rhizopus oligosporus

“…amino acids. Moreover, fermentation has the ability to mobilize the bound phenolics to improve the overall phenolic content and related antioxidant properties (3,6).…”

“…Enzymes (protease, tannase and amylase) secreted during fermentation hydrolyze complex molecular structures to simpler forms, which results in enhanced digestibility and bioavailability of nutrients including minerals (calcium and phosphorus) and limiting amino acids. Moreover, fermentation has the ability to mobilize the bound phenolics to improve the overall phenolic content and related antioxidant properties ( 3 , 6 ).…”