by Bolaji O.T., Abegunde T.A, Praise-Ofuani-Oyinloye O.C, Fashakin J.F and Apotiola Z.O.
Original Research
Impact of some processing conditions on pasting behaviour of ogi from six maize varieties soaked for 12, 24 and 36 hours and dried at 40, 50 and 60°C, respectively was evaluated. There were significant differences (p<0.05) in the pH and pasting values of ogi from all the maize varieties. High values of peak viscosities were recorded for ogi dried at 50°C irrespective of the soaking periods. Ogi from S7Y at 12th hour of soaking had it peak viscosities increased with increase in drying temperature. Similar trend was recorded for trough viscosity of ogi from A5W at 36th hour of soaking while a contrary trend was observed for breakdown viscosity of ogi at 24 and 36th hours of soaking, respectively. Highest setback viscosity of 1110.00cp was obtained at 12th hour of soaking and drying temperature of 40°C. The impact of drying temperature and starch components were more evident compared with varying soaking period of maize on ogi.
American Journal of Food Science and Technology. 2017, 5(5), 220-227. DOI: 10.12691/ajfst-5-5-8
Pub. Date: October 25, 2017
10075 Views2231 Downloads
by Damian Laryea, Faustina D. Wireko-Manu and Ibok Oduro
Original Research
This study was conducted to understand the effect of drum drying on colour, functional and pasting properties of a sweetpotato-based complementary food. Four blends of complementary flours made up of Orange fleshed sweetpotato (OFSP), millet and soybean flours were formulated based on the nutrient strength of the individual flours. The functional, pasting properties and colour of the flour blends before and after drum drying was determined. Colour intensity (ΔE) and saturation (ΔC) of formulated products increased after drum drying. Water absorption capacity (WAC) of formulations ranged from 152.5 to 216.7%, swelling index (SI) from 6.65 to 7.73, bulk density (BD) from 0.787 to 0.827 g/ml and solubility from 17.78 to 20.32%. Drum drying conditions used reduced the WAC, SI, BD and solubility of the formulations. Though the drum drying conditions used did not reduce the pasting temperature, it was able to reduce the peak time and further reduce the peak viscosity, breakdown and setback viscosities. OFSP flour could be used to develop a complementary food with improved functional and pasting properties, when complemented with millet and soybean flours and processed through drum drying.
American Journal of Food Science and Technology. 2017, 5(5), 210-219. DOI: 10.12691/ajfst-5-5-7
Pub. Date: October 19, 2017
11919 Views3042 Downloads
by Eke- Ejiofor J and Beleya E.A
Original Research
Maize is the most abundant and available component of the locally prepared gruels for human consumption in Nigeria. It has been the basic source of meal for infants and breakfast for the average family. The compositional, mineral and sensory attributes of cereal gruel (Ogi) prepared with different spices, ginger (Zingiber officinale), uda (xylopia aethiopica) and Clove (Syzygiuma romaticum) were evaluated to determine chemical, pasting and sensory properties. Chemical composition of spiced ogi samples showed significant differences (p<0.05) in all the twelve parameters evaluated. Ash content increased with the addition of spices (clove, ginger+ uda, ginger +clove). Fat content also increased with the addition of ginger as in sample B, while protein content increased for all samples with the addition of spices in singles and when combined. Carbohydrate content decreased with the addition of ginger in sample (B), Uda in sample (C) and a combination of ginger + clove in sample (F), while the other samples showed no significant difference with the control. Energy (Kcal) increased most with sample (H) which had a combination of the three spices, which is a reflection of its protein (8.01%) and carbohydrate (81.51%) respectively. Mineral content showed that magnesium ranged from 0.030 to 0.334mg/100g with the control as the lowest and sample E (Maize + Ginger + Uda) as the highest. Potassium showed no significant difference in all the samples with the addition of spice, while phosphorus had 0.071mg/100g for sample H (Maize + Ginger + Uda + Clove) as the highest. Sodium content ranged from 7.77 to 11.41mg/100g, with all the ginger containing samples having less sodium content. Pasting properties of spiced ogi (gruel) samples showed that peak, breakdown, final and setback viscosities increased with the addition of the different spices, while the pasting time and temperature reduced for all spiced ogi samples, with the control having a longer pasting time at a higher temperature. Sensory analysis result of both unsweetened and sweetened spiced ogi samples showed a significant difference (p<0.05) in all the samples with the ginger spice (sample B) been the most preferred.
American Journal of Food Science and Technology. 2017, 5(5), 204-209. DOI: 10.12691/ajfst-5-5-6
Pub. Date: October 11, 2017
11470 Views3603 Downloads
by Abdullah Muzi Marpaung, Nuri Andarwulan, Purwiyatno Hariyadi and Didah Nur Faridah
Original Research
The degradation of anthocyanins from Clitoria ternatea L. flower (CT) extract at pH 7 bottled with 0% and 50% volume of headspace (HS0 and HS50, respectively) were studied at various temperatures (7, 30, 45, 60, 75, 90°C). The extract was stable at 7°C up to 56 days. The effect of the presence of headspace to accelerate the degradation was significance at ≥30°C. The color and chemical degradation were adequately be described by the first order reaction kinetics. However, the degradation at 30°C was faster than at 45°C. The activation energy for the chemical degradation of HS0 and HS50 extracts at 45-90°C were 83.21 and 101.15 kJ/mol. The decrease of A628was the fastest, followed by A580and A550, respectively. By the evidence collected, it was proposed that the degradation of anthocyanins in CT extract was initiated by the unfolding and the deacylation of anionic quinonoidal base species.
American Journal of Food Science and Technology. 2017, 5(5), 199-203. DOI: 10.12691/ajfst-5-5-5
Pub. Date: September 26, 2017
10457 Views3556 Downloads
by Habimana Jean de Dieu, Ituze Kubana Marie Claudine, Ineza Claire and Karangwa Eric
Original Research
This study aimed to evaluate the physicochemical and bacteriological characteristics of different types of banana wine (Urwagwa) produced in Southern province of Rwanda. Both conventional (not bottled i.e from Bulinga (B) and Gahogo (GA)) and modern produced banana (bottled i.e Igisubizo from Ruli (I) and Ganzinyota from Ruvumera (G)) wines were analyzed and compared. Results showed that the alcohol content (v/v) of I, G, B and GA was 25.9% , 26.1%, 12.0% and 40.1 %, respectively while their total soluble contents were 15.2%, 12.2%, 21.7% and 21.8%, respectively. Titratable acidity (g/L) varied from 5.29 to 6.95 while pH varied from 4.45 to 3.30. The volatile acidity was found to be 0.49, 0.040, 0.147 and 0.19 g of acetic acid for wines I, G, B and GA, respectively. The turbidity was significantly higher in conventional wines than in modern ones. Sulfur dioxide content, heavy metals and minerals respected the standard norms however, potassium content (mg/L) was higher in wines B (1207) and GA (1107,21) and Pb was not recognized in all samples. Furthermore, wines GA accounted higher Escherichia coli (3 x 107 cfu/ml) and Staphylococci aureus (1.5 x 107 cfu/ml). In conclusion, these results indicated that the safety of un-bottled wine was far lower compared to that of bottled ones.
American Journal of Food Science and Technology. 2017, 5(5), 192-198. DOI: 10.12691/ajfst-5-5-4
Pub. Date: September 25, 2017
11351 Views2486 Downloads
by Emmanuel Okezie, Ugbogu Amadike E., Odungide Aggie A. and Atani Chinedu S.
Original Research
The present study evaluated the proximate, antinutritional and mineral contents of five selected vegetables consumed by Afaha Eket indigenes, Akwa Ibom State, Nigeria. Standard analytical procedures were employed in this assay. The analysed leafy vegetables include; Telferia occidentalis, Ocimum grattissimum, Lasianthera africana, Heinsia crinita and Gnetum africanum. The result of the proximate analysis showed greater amount as follows; Protein (O. grattissimum, 28.27%), fibre (O. grattissimum, 9.62%), ash (G. africanum, 7.39%), moisture (G. africanum, 10.35%), Carbohydrate (L. Africana, 47.47%) and crude fat (O. grattissimum, 8.17%) when comparatively evaluated. The Antinutritional assay revealed the presence of oxalate and phytic acid in all the tested leafy vegetables. Oxalate was highest in O. grattissimum(9.72 mg/g) and least in L. Africana (5.28 mg/g) while highest phytic acid value was recorded in T. occidentalis (18.09 mg/g) followed by G. africanum (16.29 mg/g) and least in H. crinita (7.34 mg/g). Mineral analysis of this study showed the highest concentration (mg/g) values; copper (O. grattissimum, 13.92), iron (L. africana, 3.28), magnesium (O. grattissimum, 9.49) and zinc (L. africana, 19.97). The finding of this study therefore showed that the tested leafy vegetables are nutritionally sound to the living system.
American Journal of Food Science and Technology. 2017, 5(5), 182-191. DOI: 10.12691/ajfst-5-5-3
Pub. Date: September 25, 2017
14156 Views2503 Downloads
by John O. Onuh, Gideon Momoh, Simeon Egwujeh and Felicia Onuh
Original Research
Peels of 3 varieties of mango (Julie, Peter and Paparanda) were evaluated to determine the effects of varietal differences on the nutritional, phytochemical and antioxidant properties of peels of the selected varieties. Peels from moderately ripe mango fruits were processed into mango peel flour and analyzed for their nutritional, phytochemical and antioxidant properties. The results showed that mango varieties significantly differ from each other in their nutritional compositions. Peter variety had significantly highest values in both vitamins A (β-carotene) and C while Paparanda variety had significantly lowest values. Beta-carotene content of mango peels significantly ranged from 9.14 to 11.98 µg/g while the vitamin C content ranged from 21.66 µg/g to 51.54 µg/g. There is also great variation in the phytochemical compositions of the peels of the different varieties suggesting that they might have bioactive and functional properties. DPPH scavenging activities of the mango peels are significantly different from each and are also concentration dependent. They correlated with the vitamin C and polyphenolic content. Mango peels could therefore offer low-cost dietary supplements for low income groups as well as serve as potential source of functional ingredient in processed foods for the control, management and treatment of oxidative stress induced health disorders.
American Journal of Food Science and Technology. 2017, 5(5), 176-181. DOI: 10.12691/ajfst-5-5-2
Pub. Date: September 21, 2017
10505 Views2522 Downloads
by T. Afolabi Morakinyo and A. Isaac Bamgboye
Original Research
This paper presented the optimization of the operational parameters of a biomass fire-in-tube boiler using Taguchi design method to enhance boiler thermal efficiency and throughput. Taguchi’s experimental design of orthogonal array L9 (34) was employed to generate nine runs of experiment. Response surface method was used to optimize processing parameters and validated using Taguchi’s table. Experimental results were analyzed and dependent operation parameters were predicted using linear multiple regression modeling. Hence, coefficients of correlations were established using Karl Persons’s formula. The optimum operational parameters for boiler were 2 dm2, 483.6 MJ, 100 L and 280 mm for aspirator orifice area, biomass composite, volume of cold water and vertical distance of fire grate to the kettle respectively. The coefficient of correlations between experimental and predicted values of super heated steam for temperature, pressure and volume were: 0.84, 0.96 and 0.89 respectively.
American Journal of Food Science and Technology. 2017, 5(5), 167-175. DOI: 10.12691/ajfst-5-5-1
Pub. Date: August 19, 2017
11865 Views2237 Downloads