ABSTRACT
This study investigated the impact of bioprocessing techniques (germination, solid-state fermentation, the combination of germination, and solid-state fermentation) on the physicochemical properties, anti-nutritional and bioactive constituents, in vitro digestibility, and techno-functional properties of whole wheat grains were investigated. Bioprocessed whole wheat flour (WWF) samples and the raw flour (control) were prepared using standard procedures. Proximate, anti-nutritional, mineral and amino acid (AA) compositions, protein digestibility, antioxidant activities, starch characteristics, and techno-functional properties were studied using standard methods. The bioprocessing methods increased (p ≤ 0.05) the protein (13.37-16.84 g/100 g), total dietary fiber, mineral constituents, resistant starch (7.19-9.87 g/100 g), slowly digestible starch, phenolic content, antioxidant activities (ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity), most AAs, and protein digestibility. Also observed were decreases (p ≤ 0.05) in rapidly digestible starch, phytic acid, tannin, and trypsin inhibitor activity. The adopted bioprocessing techniques modified the thermal, functional, color, and pasting properties of the WWF and resulted in molecular interactions in some functional groups, as revealed by Fourier transform infrared spectroscopy, compared to the raw flour. The combination of germination and fermentation improved the physicochemical (titratable acidity = 4.93%), protein (16.84/100 g) and starch digestibility (resistant starch = 9.87%), antioxidant (FRAP = 78.90 mg/GAE/100 g), and mineral contents (calcium = 195.28 mg/100 g), modified the pasting (peak viscosity = 90.34 RVU), thermal (peak temperature = 64.82°C), and color properties of WWF with reduced anti-nutritional factors. The combination of these processing techniques could serve as a natural and low-cost technique for the modification of whole wheat functionality and subsequently as an improved functional ingredient during food product development.
Subject(s)
Antioxidants , Flour , Resistant Starch , Triticum/metabolism , Starch/chemistry , Minerals , ProteinsABSTRACT
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. PRACTICAL APPLICATION: Bread is a staple food and this study can assist in increasing the utilization of neglected leguminous crops as well as addressing the challenge of malnutrition, prevalent in developing countries.
Subject(s)
Bread , Flour/analysis , Sphenostylis , Antioxidants , Fermentation , Phenols/analysis , TriticumABSTRACT
This study determined the effect of germination (48 h) on the physicochemical and antioxidant characteristics of rice flour from three rice varieties from Nigeria. Local rice varieties (Jamila, Jeep and Kwandala) were evaluated and compared to an improved variety (MR 219). Physicochemical and antioxidant properties of flours were determined using standard methods. Protein, magnesium, phosphorus, potassium and antioxidant properties of rice flours increased after germination while phytic acid and total starch contents decreased. Foaming capacity and stability of rice flours increased after germination. Germination resulted to changes in pasting and thermal characteristics of rice flours. Germinated rice flours had better physicochemical and antioxidant properties with reduced phytic acid and starch contents compared to MR 219, which can be utilized as functional ingredients in the preparation of rice-based products.