The role of dietary fibre on the water-holding capacity (WHC), as a functional property of starchy legumes, was investigated. The WHCs of butter beans, broad beans and lentils were found to be in the range 1.35-1.82 g water/g in the raw forms, and in the range 1.81-2.63 g water/g for the cooked forms, with a contribution of 35.9-56.1% by the equivalent fibre-rich fractions (FRFs). Non-starch polysaccharides (NSPs) were found to be in the range 14.1-18.1 and 27.1-38.1 g/100 g for the three legumes and their FRFs, respectively. Arabinoxylans, which enhance the WHC, were found at levels of 8.6-11.6% concentration in the NSPs of the FRFs.

This study describes the constituents and properties of bitter lupine (BL) (Lupinus termis) and sweet lupine (SL) (Lupinus albus) seed oils in addition to oligosaccharides content in seed flour; each can be beneficial for consumers. There was a significant difference in saponnification number and ester value of both oils. The peroxide value was found (1.80 ± 0.20 meq/kg in BL seed oil compared to 1.89 ± 0.29 meq/kg in SL seed oil. Fatty acids (FA) composition showed that total unsaturated FAs were higher, (88.33 %) in BL seed oil than (87.25 %) in SL seed oil; both values markedly higher than saturated FA content. The major FA in both samples is oleic FA, (50.23 %) in BL and 45.00 % in SL. Essential FAs were found higher (39.80 %) in SL; compared to (36.11) in BL. Total phenols were significantly higher in BL seed oil (58.99 mg/kg); than.SL seed oil (50.95 mg/kg). The oil classes: triglycerides, free FA steroids and alcohols were found higher in SL seed oil; while hydrocarbons, mono-glycerides, di-glycerides and phospholipids were higher in BL seed oil. Total oligosaccharides were found significantly higher (9.74 ± 0.20 g/100 g) in BL flour compared to 8.99 ± 0.10 g/100 g in SL flour; with stachyose in concentrations of 3.9 ± 0.10 g/100 g and 3.88 ± 0.03 g/100 g; respectively.

The bile acid binding to undigestible fibre has a significance on bile acids excretion. This was known to result in lowering blood cholesterol (for the use of cholesterol in bile acid formation) as well as reducing the colorectal cancer risk (through decreased formation of secondary bile acids). Compared to the model fibres Solka floc and carboxymethylcellulose (CMC), the investigated fibre fractions of lentils, broad beans and butter beans, were found to bind more cholic acid and chenodeoxycholic acid under conditions simulating the small intestine.

Anti-nutritional studies on cowpea (Vigna ungiculata L.) seeds as whole cowpea flour (WCF), dehulled cowpea flour (DCF), dehulled defatted cowpea flour (DDCF) and protein isolates obtained from DDCF by isoelectric (CPIA) and micellization (CPIB) precipitation. The protein content of WCF and DDCF were 22.3% and 26.75% respectively, while CPIA and CPIB showed 75% and 76% respectively. The abundant minerals in WCF and DCF were calcium (32.38-33.61 mg/100 g); potassium (29.25-24.99 mg/100 g); and sodium (1.76-1.00 mg/100 g). The least abundant minerals were iron (0.004-0.013 mg/100 g); copper (0.04-0.25 mg/100 g); manganese (0.18-0.30 mg/100 g) and zinc (0.26-1.22 mg/100 g); respectively. Trypsin inhibitor activity for WCF, CPIA and CPIB was found 16,640 TIU/g, 4293 TIU/g and 4290 TIU/g respectively. Condensed tannins in RCF and DDCF were found 0.003% and 0.004% respectively while phytic acid content 0.8% and 1.17% respectively, no phytic acid and tannins were observed in protein isolates. Cowpea flour was also similar to other edible grain legumes in content of anti-nutritional factors; appropriate processing methods improved cowpea nutritive value and significantly reduced the levels of antinutritional factors.

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