Hydrothermal treatments of Finger millet (Eleusine coracana) starch

The effect of hydrothermal treatments on the properties of Finger millet starch was investigated. Finger millet was modified by heat-moisture treatment, HMT at 100 °C, 16 h; 20% moisture level (MHT-20), 25% moisture level (MHT-25) and 30% moisture level (MHT-30) and annealed, ANN at 50 °C for 48 h (MAN). Results of the pasting characteristics shows that MNS and MAN were indicative of type ‘B’ starch which is characteristic of normal cereal starches, while HMT starches were Type ‘C’ which is characteristics of cross-linked or legume starches. MNS belonged to the type ‘A’ pattern of cereal starches. X-ray diffractometry studies (XRD) show that MNS gave strong peaks centered at 23.5, 20.3, 18.2, 17.15, and 15.15 Å, while HMT and ANN starches retained the typical ‘A’ pattern. Scanning electron microscopy (SEM) studies show that the shape and surface characteristics of the starches were irregular, polygonal-shaped granules, with less than 1% cavity or ruptured granules. Modification did not affect the appearance. All the starches swell as the temperature increased in the order MNS>MAN>MHT-20>MHT-25>MHT-30, and solubilized at different rate in the following order: MHT-30>MHT-20>MHT-25>MAN>MNS. The gelation profile of the starches ranged from 4 to 8% (w/v), while its oil and water absorption capacity ranged from 1.90 to 2.50 and 2.75 to 3.25 g/g, respectively.     

Effect of selected Hofmeister anions on functional properties of protein isolate prepared from lablab seeds (Lablab purpureus)

Effects of selected Hofmeister anions, namely Na₂SO₄, NaCl, NaBr, NaI, NaClO₄ and NaSCN, on the functional properties of a protein isolate prepared from lablab seeds (Lablab purpureus) were investigated. The results of water absorption capacity indicated that highest water absorption was recorded in solutions of Na₂SO₄, and the lowest in NaSCN solutions. Reduction in water absorption capacity followed the Hofmeister series in the order Na₂SO₄ > NaCl > NaBr, NaI > NaClO₄ > NaSCN. Protein solutions prepared in chaotropic (NaI, NaClO₄, NaSCN) salts had better foam capacity, foam stability, emulsifying activity and emulsion stability than solutions prepared with kosmotropic salts (Na₂SO₄, NaCl, NaBr). The results also indicate that increase in foam capacity and stability followed the Hofmeister series in the order Na₂SO₄ < NaCl < NaBr, NaI < NaClO₄ < NaSCN. When least gelation concentration (LGC) was used as the index of gelation capacity, at various salts concentrations, the lowest LGC were observed in NaSCN and the highest LGC in protein solutions prepared with Na₂SO₄. Copyright © 2005 Society of Chemical Industry     

Mobile apps usage and dynamic capabilities: A structural equation model of SMEs in Lagos,Nigeria

Significant knowledge exists regarding the application of dynamic capability (DC) frameworks in large firms, but their impact on smaller organisations is yet to be fully researched. This study surveyed 1162 small and medium sized enterprises (SMEs) in Lagos in an effort to understand how SMEs in developing country contexts use mobile apps to enhance their businesses through DCs. Through the use of the covariance-based structural equation modelling (SEM) technique, the study explored the fitness of a conceptual formative model for SMEs. The model assembled 7 latent variables namely: mobile app usage, adaptive capability, absorptive capability, innovative capability, opportunity sensing ability, opportunity shaping ability and opportunity seizing ability. Subsequently, 15 hypotheses aimed at testing the relationships between the latent variables were developed and tested. The findings revealed that mobile app usage increases the adaptive, absorptive and innovative capabilities of SMEs. Absorptive capabilities help SMEs to maximise opportunities, while innovative capabilities negatively influence SMEs’ tendency to maximise opportunities. The results failed to establish a direct relationship between mobile app usage and SMEs’ ability to maximise opportunities. The research outcomes indicate that SMEs in Lagos respond to opportunities innovatively but they seldom exhibit innovation in order to create opportunities. The heterogeneous nature of SMEs complicates any clear-cut narrative as to how SMEs in Lagos should employ mobile apps to create and maximise opportunities. However, mobile apps could induce innovation and, as such, impact significantly when developed and applied to the contextual requirements of SMEs. The research revealed the untapped potential of SMEs’ mobile app usage in Lagos.     

On 3-stage geometric explicit Runge–Kutta method for singular autonomous initial value problems in ordinary differential equations

There has been considerable efforts to increase the efficiency of explicit Runge–Kutta (ERK) methods over the years. However, this always lead to increase in the number of terms of the Taylors’ series incremental function. In this work, a 3-stage geometric explicit Runge–Kutta method for solving autonomous initial value problems in ordinary differential equations is derived and implemented. The computational results show that the method is stable, efficient and accurate. We also compared this method with some other conventional methods.     

Optimization,kinetics, physicochemical and ecotoxicity studies of Fenton oxidative remediation of hydrocarbons contaminated groundwater

Fenton oxidation remediation of hydrocarbons contaminated groundwater was investigated for efficiency and effectiveness. 10% pollution was simulated in the laboratory by contaminating groundwater samples with diesel and domestic purpose kerosene (DPK) in two different experimental set ups. Optimum conditions of concentrations of the treatment solutions and pH were established: 300 mg/L (FeSO₄), 150,000 mg/L (H₂O₂) and pH = 3 for the kerosene contaminant; 100 mg/L (FeSO₄), 300,000 mg/L (H₂O₂) and pH = 3 for the diesel contaminant. The results from kinetics study show that the remediation process is pseudo-first order reaction with a rate constant of 8.07 × 10⁴ mgL^?1hr^?1 and 3.13 × 10⁴ mgL^?1hr^?1 for the diesel and kerosene contaminants in that order with 95.32% and 79.25% reduction in chemical oxygen demand (COD) for diesel and kerosene contaminated samples at the end of the remediation process respectively indicated that remediation have occurred significantly. Percent reduction in Total Petroleum Hydrocarbon (TPH) as kerosene was 89.84% and that of the diesel contaminant as 91.87% after 6 hours of remediation. The general pollution index (GPI) for the hydrocarbons contaminated samples was in the range of 6.70–7.52 against the background value of 4.39 for the control groundwater sample. After treatment the GPI had dropped to 4.13–4.43 which depicts remarkable remediation although the samples remained impaired. Therefore there is the need of post-treatments to make the groundwater fit for domestic and agricultural uses. The application of the Fenton oxidative process is found to be very efficient, effective and rapid in reducing total petroleum hydrocarbon as kerosene and diesel as target contaminants.     

Effect of succinylation on the physicochemical,rheological, thermal and retrogradation properties of red and white sorghum starches

Starches isolated from red and white sorghum were modified with succinylation. After modification proximate composition, moisture content, ash, protein and fat were reduced in percentage. Increase in swelling power was observed and did not show any significant change in solubility. Swelling and solubility were pH dependent with higher values obtained at pH 12 in both native and modified starches. At pH 4 both succinylated red and white starches had lower solubility.     

Effect of annealing and heat moisture conditioning on the physicochemical characteristics of Bambarra groundnut (Voandzeia subterranea) starch

Isolated starch of Bambarra groundnut (Voandzeia subterranean) was subjected to hydrothermal modifications through annealing and heat moisture conditioning. Both annealing and heat moisture conditioning reduced the swelling power and solubility of the starch. Water binding capacity reduced after annealing heat moisture conditioning at 18% moisture level (HMB18) and heat moisture conditioning at 21% moisture level (HMB21). Both heat moisture conditioning at 24% moisture level (HMB24) and heat moisture conditioning at 27% moisture level (HMB27) increased the water binding capacity. Hydrothermal modifications reduced the oil absorption capacity of the raw starch. Annealing and heat moisture conditioning reduced the peak viscosity (Pv), viscosity at 95 degrees C (Hv) and viscosity at 95 degrees C after 30 min holding (Hv30). However, viscosity increased on cooling down to 50 degrees C after annealing. Annealing and heat moisture treatments as revealed by scanning electron micrograph and light micrograph did not alter the shape and size of the raw starch. The results indicate a rearrangement within the starch granule following hydrothermal treatments.