Effect of Extrusion Variables on the Hydrogen Cyanide and Haemagglutinin Content of Extruded Blends of Cassava Products and African Yam Bean

High quality cassava flour (CF) and African yam bean (AYB) flour  were blended together , also pregelatinized, shreaded cassava chips (Ighu) and AYB flour were blended separately using feed ratios of 0.54:99.46, 20:80, 50:50, 80:20, 99.46:0.54 (AYB/CF or AYB/Ighu) The extruder screw speed and the moisture content of the blends were also varied. The samples were extruded using a single screw extruder. Hydrogen cyanide content and haemagglutinin contents of the extrudates and the raw samples were determined. The data obtained were statistically analyzed using response surface methodology. The results obtained showed that there were no significant difference (p > 0.05) in the linear, quadratic and interaction for moisture content and screw speed, but there were significant difference in the linear and quadratic effects of feed composition on the hydrogen cyanide of the samples. The results also showed that extrusion cooking affected the hydrogen cyanide content of AYB/Ighu blends more than the cassava flour/AYB blends. The values obtained were below the Industrial Standard for cassava and cassava products. The residence time of the feed material had significant effect on the reduction of haemagglutinin content of the end products. The model for AYB/ Ighu was adequate more than that of AYB/CF. Keywords: Hydrogen cyanide, haemagglutinin, extrusion, cassava, African yam bea

Physico-chemical properties of wheat-yam flour composite bread

AbstractThis work investigated the effect of yam flour substitution on characteristics of wheat bread and also determined the functional properties of the experimental flour samples. Flours were obtained from three varieties of yam (Dioscorea rotundata, Dioscorea alata and Dioscorea bulbifera) and blended with wheat flour at 25, 50 and 75 percent levels of substitution for bread production. Wheat flour (WF) and each of the yam flours were used as the positive and negative controls respectively. The functional properties (bulk density, water/oil absorption capacities, emulsion activity) of the flour samples were determined while the proximate, physical and sensory characteristics of loaves were also determined. The functional properties of the flour samples ranged from 0.42g/ml to 0.67g/ml packed bulk density; 0.39g/ml to 0.47g/ml loose bulk density; 0.88ml/g to 2.10ml/g oil absorption capacity; 1.50ml/g to 3.90ml/g water absorption capacity and 43.75% to 49.37% emulsion activity. The proximate composition of the bread samples ranged from 26.82% to 38.90% moisture, 4.23% to 5.10% fat, 6.10% to 9.25% protein, 1.90% to 2.45% ash, 0.12% to 0.64% crude fiber and 46.43% to 56.71% carbohydrate. The volume, weight and specific volume of loaves varied from 200ml to 400ml, 142.6g to 170.2g and 1.18ml/g to 2.81ml/g respectively. The crack formation of bread samples showed that there were no cracks on wheat bread (WF) and 25% yam flour substituted breads while 100 percent yam flour breads had large cracks. The sensory properties of the 25% yam flour substituted breads were statistically (p>0.05) the same with the 100% wheat bread but differed from all the other bread samples. The mean score of the sensory attributes decreased as yam flour increased in the formulation. Sensory Evaluation of the bread samples showed that substitution level of 25% yam flour produced bread that was acceptable to the consumers whereas up to 50% and above were not acceptable. It is therefore recommended that substitution level of not more than 25% yam flour be used for yam/wheat composite bread production

Expansion ratio and bulk density of extruded blends of african yam bean and Ighu

No Abstrac

Effects of Processing on the Nutrient Composition of False Yam (Icacina trichantha) Flour

False yam (Icacina trichantha) tubers were processed into different flour samples: the raw; steeped-sun-dried; steepedoven- dried; blanched-sun-dried and blanched-oven-dried samples. The nutrient composition: proximate and mineral elements  contents of the flour samples were studied. The lipid, protein and carbohydrate contents of the samples ranged between 1.77 to 5.76%, 3.01 to 60.3% and 85.56 to 93.31% respectively, while the energy values ranged between 394.27 to 412.46 Kcal.  Concentration of potassium, sodium, calcium and iron (among others) ranged between 20.835 and 31.51 mg/l, 2.409 and 18.890 mg/l, 90.250 and 112.550 mg/l to 0.777 and 2.840 mg/l respectively. False yam tuber, apart from being a good source of energy for man, is rich in mineral elements (potassium, sodium and calcium). Processing affected the levels of nutrients, in the flour samples.Keywords: Processing, nutrient, false yam tuber

Comparative Evaluation of Blood Glucose Regulating Potential of CocaCola Zero Coke and Common Coke

Current changes in lifestyle due to increasing incidence of diabetics, high blood pressure, stroke and obesity have made people to be skeptical on their sugar intake. In compliance to this, Coca-Cola introduced Diet Coke, CaffeineFree Coca-Cola, Diet Coke Caffeine-Free, Coca-Cola Zero Sugar among others. Blood glucose regulating potential between Zero and common Coke was compared using 25 male student participants randomly selected from volunteers of Michael Okpara University of Agriculture, Umudike Abia State Nigeria for the study. They were given each a bottle of 35 cl of Zero Coke, 35 cl common Coke and 50 g glucose (standard) at different days after 12 h fasting and their blood sugar levels were measured at every 15 min intervals for 2 h on each day. The results showed that Zero Cokedecreased the blood sugar level from 78.28 (0 min) to 78.00 (15 min), increased same thereafter to 85.76 (60 min) and decreased to 75.96 (120 min) lower than common Coke and the standards. Common Coke increased from 91.44 (0 min) to 115.60 (15 min) and finally decreased from 95.76 (60 min) to 81.68 (120 min). Mean glycemic index of Zero Coke (11.095) was significantly (p<0.05) lower than common Coke (31.140). Glycemic index of the individual participants for Zero Coke was less than 14 while that of common Coke ranged from 15 to 64.The incremental area under curve (IAUC) for Zero Coke was 377.46 and normal Coke was 1173.20. Zero Coke significantly lowered blood glucose than common Coke. Keywords: Blood glucose, glycemic index, Zero Coke, common Coke

Pasting and functional properties of lafun and starch processed from some improved cassava genotypes in Nigeria.

Twenty eight cassava genotypes resistant to the dreaded cassava mosaic disease were randomly selected from the National Root Crops Research Institute Umudike, farm. The cassava samples were processed into starch and lafun, and their pasting and functional properties were assessed. Also amala was obtained from the lafun and examined for sensory characteristics of smell, hand feel (stickiness), appearance and general acceptability. Results show that the pasting properties (gelatinization temperature, Peak viscosity, Viscosity at 92oC after 15 min of heating and Stability) fell within reported values. The values ranged from 1020 BU for sample 95/0166 to 2500 BU for samples 98/2101, TMS 96/1565 and TME 419. The peak viscosity of the lafun samples ranged from 920 BU for sample 95/ 0166 to 2500 BU for samples 96/1089, 98/0068, TMS 96/ 1565, 94/0561 and M98/0068. The value of the peak viscosity of the starch sample was higher than that of the lafun sample in most cases. Bulk density of the starch samples ranged from 1.43g/cm3 for TMS97/22053 to 33g/cm3 for M98/006. On the other hand, the Bulk density of the lafun samples ranged from 0.08 cm3 for TMS 96/1565 to 1.96cm3 for TMS 92/0067. Water absorption capacity of the starch samples ranged from 0.5g/ml for samples TMS 98/2101 and 99/3073, to 2.0g/ml for sample TMS 98/0510. The values for the lafun samples ranged from 0.5g/ml for TMS 99/2123 to 2.5g/ml for TMS 30572. All the samples were on the average acceptable to the panelists having scored an average of 4.00 on a scale of 7

Production and evaluation of wafers from blends of Ighu and African yam bean flour.

No Abstrac

Proximate and sensory properties of fruit juice produced from varieties of watermelon (Citrullus lanatus).

 No Abstrac

Pasting and functional properties of lafun and starch processed from some improved cassava genotypes in Nigeria.

Twenty eight cassava genotypes resistant to the dreaded cassava mosaic disease were randomly selected from the National Root Crops Research Institute Umudike, farm. The cassava samples were processed into starch and lafun, and their pasting and functional properties were assessed. Also amala was obtained from the lafun and examined for sensory characteristics of smell, hand feel (stickiness), appearance and general acceptability. Results show that the pasting properties (gelatinization temperature, Peak viscosity, Viscosity at 92°C after 15 min of heating and Stability) fell within reported values. The values ranged from 1020 BU for sample 95/0166 to 2500 BU for samples 98/2101, TMS 96/1565 and TME 419. The peak viscosity of the lafun samples ranged from 920 BU for sample 95/ 0166 to 2500 BU for samples 96/1089, 98/0068, TMS 96/ 1565, 94/0561 and M98/0068. The value of the peak viscosity of the starch sample was higher than that of the lafun sample in most cases. Bulk density of the starch samples ranged from 1.43g/cm3 for TMS97/22053 to 33g/ cm3 for M98/006. On the other hand, the Bulk density of the lafun samples ranged from 0.08 cm3 for TMS 96/1565 to1.96cm3 for TMS92/0067.Water absorption capacityof the starch samples ranged from 0.5g/ml for samples TMS 98/2101 and 99/3073, to 2.0g/ml for sample TMS 98/0510. The values for the lafun samples ranged from 0.5g/ml for TMS 99/2123 to 2.5g/ml for TMS 30572. All the samples were on the average acceptable to the panelists having scored an average of 4.00 on a scale of 7