Processing Effects on Chemical,Functional and Pasting Properties of Cowpea Flour from Different Varieties

Cowpea varieties (IT88D-867-11, IT89KD-288 and MALA) were boiled, roasted, dehulled and later milled into powder. The proximate composition, functional and pasting properties as well as anti-nutritional contents (Tannin) of the product was subsequently determined. The result of the study revealed significant increase (P < 0.05) in the crude protein, crude ash, swelling power and water absorption capacity. Conversely, significant decrease (P < 0.05) was observed in crude fat, starch content, moisture content, solubility and peak viscosity. Boiled samples have significantly higher (P < 0.05) crude protein, swelling power, water absorption capacity, with concomitantly lower solubility and tannin content. Crude ash, moisture, solubility and tannin content of dehulled samples decreased significantly with an increase in protein, swelling power and water absorption capacity. However, IT89KD-288 has the highest protein content irrespective of the processing used. But raw IT89KD-288 showed highest percentage of swelling power, solubility, water absorption capacity and Tannin content. The result revealed that both boiling and dehulling will greatly reduce tannin content of cowpea.     

Utilization of African grains for sourdough bread making

Abstract: Acha and Iburu flours were singly subjected to sourdough fermentation with previously selected autochthonous starters. Sourdoughs were used (30%, wt/wt) as aroma carriers and acidifiers during short time fermentation with the addition of baker's yeast. Acha and Iburu sourdough breads were compared to wheat sourdough bread started with the same strains and to breads made with the same formula but using baker's yeast alone. During Acha and Iburu sourdough fermentations, starter lactic acid bacteria reached almost the same cell density found in wheat sourdoughs. Acidification was more intense. Iburu sourdough bread had the highest total titratable acidity, the lowest pH, and contained the highest levels of free amino acids and phytase activity. The values of in vitro protein digestibility did not differ between Acha sourdough and wheat sourdough breads, while Iburu sourdough bread showed a slightly lower value. Acha and Iburu sourdough breads showed lower specific volume and higher density with respect to wheat sourdough breads. Nevertheless, Acha and Iburu sourdough breads were preferred for hardness and resilience. As shown by sensory analysis, Acha and especially Iburu sourdough breads were appreciated for color, acid taste and flavor, and overall acceptability. Practical Application: This study was aimed at evaluating the technological and nutritional properties of the African cereals Acha and Iburu. Sourdough fermentation and the use of selected starters increased the nutritional and sensory qualities and the potential application for bakery industry.     

Functional properties of selected starter cultures for sour maize bread

This paper focuses on the functional properties of maize sour-dough microflora selected and tested for their use as starter cultures for sour maize bread. Lactic acid bacteria and yeasts isolated from spontaneously fermented maize dough were selected based on dominance during fermentation and presence at the end of fermentation. Functional properties examined included acidification, leavening and production of some antimicrobial compounds in the fermenting matrix. The organisms previously identified as Lactobacillus plantarum, Lb. brevis, Lb. fermentum, Lb. acidophilus, Pediococcus acidilactici, Leuconostoc mesenteroides and Leuconostoc dextranicum and Saccharomyces cerevisiae were used singly and as mixed cultures in the fermentation (fermentation time: 12h at 28+/-2 degrees C) of maize meal (particle size >0.2mm). The pH fell from an initial value of 5.62-3.05 in maize meals fermented with Lb. plantarum; 4.37 in L. dextranicum+S. cerevisiae compared with the value for the control (no starter) of 4.54. Significant differences (P 相似文献   

Decoding movement intent patterns based on spatiotemporal and adaptive filtering method towards active motor training in stroke rehabilitation systems

Neural Computing and Applications - Upper extremity (UE) neuromuscular dysfunction critically affects post-stroke patients from performing activities of daily life. In this regard, various...     

Effect of chemical preservatives on shelf life of mushroom (Pleurotus ostreatus) cultivated on cassava peels

Short shelf life is a major impediment to the processing and distribution of mushroom. The effect of chemical preservatives on some quality attributes of mushroom during storage was investigated. Mushroom were soaked in four preservatives at two concentrations for 10 mins, packaged, stored at 4 °C for 30 days and analysed at intervals for their microbial population, colour, firmness and weight loss. Sodium benzoate (0.05%, 0.1%) lost its preservative effect on all the micro‐organisms enumerated after 3 days, and samples treated with 0.1% potassium sorbate had the lowest microbial load at the end of the storage period. Change in colour of the potassium sorbate (0.1%)‐treated sample was lower than and significantly different from the citric acid (2%, 4%)‐treated samples. The values of the firmness of the 4% citric acid preserved mushroom were significantly different (P ≤ 0.05) from other samples throughout the storage period. There was a significant negative correlation (r = ?0.807, P < 0.01) between the firmness and weight loss of the preserved mushroom. Potassium sorbate (0.1%) and citric acid (4%) extended the shelf life of mushroom for 24 days.     

The pasting,chemical and sensory properties of biofortified cassava root starch-based custard powder

The effect of biofortified cassava root starch (YfCRS) (90–98 %) and whole egg powder (WEP) (2–10 %) on the pasting, chemical and sensory properties of cassava starch-based custard powder (CbCP) were studied using response surface methodology. The result revealed that there are variations in the pasting properties of the CbCP notwithstanding the levels of WEP inclusion, and all the custard powder could form paste below the boiling point of water at the peak time of <5 min. Additionally, the CbCP with high quantity of WEP had the highest protein (6.39 %), iron (29.39 mg/kg) and zinc (4.25 mg/kg) contents, but with low amylose (18.68 %) and trans-β-carotene (0.0756 μg/g) contents. The YfCRS increased the amylose and trans-β-carotene contents of the custard powder. The models for the responses were highly adequate (R² > 80 %), except for peak viscosity, pasting temperature, hydrogen cyanide and overall acceptability. Although all the sensory attributes of the formulated CbCP gruel fall within the likeness range, 93.13 % YfCRS and 7.56 % WEP is the optimum combinations for good quality CbCP. Therefore, to replace maize starch with cassava starch in the production of a quality CbCP, 93.13 % YfCRS and 7.56 % WEP could be used.     

Enrichment of Noodles with Soy Flour and Carrot Powder

Noodles were produced from four flour blends of whole wheat, wheat-cassava, wheat-cassava-soy flour and wheat-cassava-carrot flour blends respectively. The flours were analyzed for proximate analysis, functional properties and total carotenoid content. The cooking time of all samples was also determined. Results show that there were significant differences (p < 0.05) between values obtained for moisture content, protein and total carbohydrates (p < 0.05) while values for fat and ash contents of the samples were not significantly different (p > 0.05). The functional properties also showed significant differences (p < 0.05) between the pasting properties except for pasting temperature and the cooking time of the samples. The total carotenoid content of the dried carrot sample was found to be 28.34 mg/100 g dry weight basis, while the noodle sample containing 10% dried carrot sample (CSC4) had a total carotenoid content of 1.80 mg/100 g dry weight basis. The results suggest that noodles made from the different flour blends can compare favourably with conventional noodles made from wheat flour in quality and that carrot flour can be used for noodle enrichment.     

Exploitation of Acha (Digitaria exiliis) and Iburu (Digitaria iburua) flours: Chemical characterization and their use for sourdough fermentation

This study aimed at characterizing the chemical and microbiological composition of Acha (Digitaria exiliis) and Iburu (Digitaria iburua) flours and at exploiting their potential for sourdough fermentation. Both the flours had a gross composition similar to other cereals. As shown by two-dimensional electrophoresis analysis, Acha flour had a higher number of prolamins with respect to Iburu flour. The opposite was found for the number of glutelin spots. The concentration of total free amino acids of Iburu flour was higher than that of Acha flour (1348 ± 34 vs. 100 ± 20 mg/kg). Pediococcus pentosaceus was the dominant species in both the flours. Several isolates were used to ferment Acha or Iburu flours. After 8 h fermentation at 30 °C, pH ranged from 3.41 to 3.83 and from 4.20 to 4.66 for Acha and Iburu sourdoughs, respectively. The highest values of TTA and concentration of lactic acid were found in almost all Iburu sourdoughs. The synthesis of acetoin and γ-amino butyric acid (GABA) was only found in Iburu sourdoughs. Data from the kinetics of acidification, synthesis of lactic and acetic acids, acetoin, and liberation of total free amino acids were elaborated by Principal Component Analysis. Sourdoughs from Acha and Iburu flour were clearly differentiated.