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Bechoff A.,University of Greenwich | Chijioke U.,National Root Crop Research Institute | Tomlins K.I.,University of Greenwich | Govinden P.,University of Greenwich | And 3 more authors.
Journal of Food Composition and Analysis | Year: 2015

The carotenoid composition of gari made from biofortified cassava (BG) was compared to that of existing gari of similar appearance but made from white cassava with added red palm oil (RPG). Storage of both yellow gari products was modelled at ambient temperatures typical of tropical areas (19-40°C) over a 3-month-period at constant relative humidity. Carotenoid content and hence vitamin A activity of the gari products decreased markedly with time and temperature. Trans-β-carotene degradation fitted well the kinetics predicted by the Arrhenius model, in particular for BG. Activation energies for trans-β-carotene were 60.4 and 81.0kJmol-1 for BG and RPG respectively (R2=0.998 and 0.997, respectively); hence the minimum energy to cause degradation of trans-β-carotene in gari was lower with BG. Rates of degradation of 9-cis-β-carotene in gari were of the same order as with trans-β-carotene. Although the initial content of trans-β-carotene was twice as high in the BG compared to RPG, trans-β-carotene in BG degraded much faster. Results showed that the average shelf life at ambient temperature for BG was significantly shorter than for RPG and therefore carotenoids in BG were less stable than in RPG. © 2015 The Authors.Published by Elsevier Inc. Source

Adaku U.E.,National Root Crop Research Institute | Okafor P.N.,Michael Okpara University of Agriculture
Electronic Journal of Environmental, Agricultural and Food Chemistry | Year: 2010

The processing effect on the cyanogenic potential of roots of two new cassava cultivars (TME 419 and TMS 98/0505) obtained from the germplasm bank from Centro Internacional de Agricultura Tropical (CIAT) Cali, Colombia and grown at National Root Crops Research Institute (NRCRI) Umudike, Nigeria was studied using spectrophotometric method. These cultivars are planted and distributed to farmers by NRCRI, Umudike but have not been assessed for cyanogenic potential under their new climatic environment before and after processing. The cyanogenic potential of the root pulp in their unprocessed form ranged 40.0 + 0.2 to 60.0 + 0.3mgCN-kg-1, while processing into gari and oven dried chips resulted in cyanogenic potential of 0.29 + 0.01mgCN-kg-1 for TME 419 cultivar and 0.2 + 0.05mgCN-kg- 1 for TMS 98/0505 for gari and 36.06mgCN-kg-1 for TME 419 and 34.16mgCN-kg-1 for TMS 98/0505 respectively for the chips. Therefore, the use of the processing methods used in this study has drastically reduced the cyanogenic potential of the product to safe levels. Source

Eluagu E.N.,National Root Crop Research Institute | Onimawo I.A.,Ambrose University
Electronic Journal of Environmental, Agricultural and Food Chemistry | Year: 2010

Studies were conducted on the mineral composition and antinutritional factors of flours produced from two improved orange fleshed sweet potato (OFSP) genotypes (CIP199004.2 and CIP440216), which were processed using two treatments; the unblanched and blanched method. The sweet potato roots were stripped and the striped samples shared into two portions; one portion was unblanched, washed, drained and oven (Gallenkamp, model OV- 160) dried while the other portion was blanched in hot water (90°C) for 5 minutes, drained and oven dried. The dried samples were milled and later sieved (0.2mm) into flour for mineral and antinutritional analysis. The results showed that the mineral contents of both unblanched and blanched OFSP flour samples differed due to processing and varietal effect with the unblanched flour samples having slightly higher β-carotene content value than the blanched OFSP flour samples. The β-carotene values of CIP 199004.2 flour samples were 3.48 μg/g (unblanched) and 1.54μg/g (blanched), while CIP 440216 was 5.48μg/g (unblanched) and 4.24μg/g (blanched). The iron content of the unblanched CIP 440216 had a slightly higher value of 0.84mg/g than unblanched CIP 199004.2 (0.63mg/g). The phytate content in unblanched OFSP flour samples seemed relatively higher than the blanched OFSP flour samples and may be as a result of the processing method as it affected the phytate content through leaching process. The result obtained from tannins was generally low. In effect, it seems that utilizing orange fleshed sweet potato in their raw (unblanched) form retains the nutrients more than in their processed form. Source

Udensi U.E.,University of Port Harcourt | Udensi U.E.,International Institute Of Tropical Agriculture | Tarawali G.,International Institute Of Tropical Agriculture | Ilona P.,International Institute Of Tropical Agriculture | And 2 more authors.
Journal of Food, Agriculture and Environment | Year: 2012

Various factors influencing the adoption of weed control technologies in Abia State were studied. A multi-stage random sampling procedure was used to select 510 cassava farmers in 2006. Results showed that 56.5% of the respondents were females, that are largely (90.2%) in their productive years. Most (78.8%) of the total respondents were married, 83.3% attended formal schooling, 74.9% had households of more than 5 persons. All the respondents were basically smallholder farmers; with 46.9% were full time farmers. Fifty percent of the respondents had secure tenurial arrangements; 92.9% had more than 6 years of farming experience. Probit analysis shows that factors related to the adoption of weed control technologies were gender at 5% in the negative direction in Abia North (Zone 1) and 10% in the positive direction in Abia Central (Zone 2); age at 5% negatively in Zone 1, educational status at 5% in the positive direction in Zone 1 and 10% pooled (entire State), house-hold size at 5% and 1% positively in Zone 2 and the entire State, respectively. The coefficient for yield was positive and highly significant in Zone 1 and the entire State, the tenurial system was negative and significant at 5% level in Zone 2, as well as application problems but at 5% in Zone 1 and 10% pooled. Training on weed control and average income was positive and significant at 1% as well as farming experience at 5%. The coefficient for no definite market was negative and significant at 5% in Zone 1. The coefficient for the high cost of chemicals had a negative relationship with the adoption of chemical weed control technologies and was significant at the 1% level in Zone 2 and the entire State. The probit model for Abia South (Zone 3) could not be estimated because the percentages responding at all doses were the same. Hence policies should be adopted aimed at improving the educational levels of the farmers and encouraging the experienced farmers to increase adoption would be necessary; there is a need for the intensification of training and educational programs for the potential adopters of the weed control practices; programs that target both gender groups to ensure the equitable adoption of chemical control practices between males and females. Policies need to be designed to convert tenurial arrangements to more secure forms to increase the rate of adoption of weed control technology by the creation of markets for cassava, and the provision and subsidization of chemicals for weed control. Source

Agahiu A.E.,University of Nigeria | Udensi U.E.,University of Port Harcourt | Udensi U.E.,International Institute Of Tropical Agriculture | Tarawali G.,International Institute Of Tropical Agriculture | And 3 more authors.
African Journal of Agricultural Research | Year: 2011

This study assessed the determinants of weed management strategies on yield of cassava in Kogi State, Nigeria using the ordinary least square regression analysis. A multi-stage random sampling technique was used to select 450 cassava farmers in the state in 2009. The result showed that there was a significant difference in the yield of cassava between plots applied with herbicides and plots without herbicide application. The common herbicides used by the farmers were Primextra Gold(Atrazine 370 g + S-metolachlor 290 g per litre), Galex ® (Metobromuron 250 g + Metolachlor 250 g per litre), Cotoran multi® 500EC (Fluometuron 250 g + metolachlor 250 g per litre), Codal Gold ® 412.5DC (250 g prometryn + 162.5 g per litre) and Fusilade Forte® 150 EC (150 g Fluazifop-p-butyl per litre) and Dual Gold ® (960 g S-metolachlor per litre). Except Fusilade Forte ® that was applied post-emergence to the weeds, the herbicides were mostly applied preemergence to both crops and weeds. Mean yield of cassava for plots applied with herbicides was 8,199 kg/ha and 6,999 kg/ha for plots with zero herbicide application. The study found a significant (p ≤ 0.05) negative relationship between age of farmer and cassava yield. Education, use of herbicides, hand weeding, slashing and intercrop with melon had a significant (p ≤ 0.01) positive relationship with cassava yield. The coefficients for household size, farming experience and intercrop with okra (Abelmoschus esculentus L. Moench) were positively associated with cassava yield at 10.0% level of probability. Implicit in these results is that weed management strategies should be aimed at the use of herbicides, subsequent hand weeding or slashing, as well as intercrop with crop such as okra and melon (Colocynthis citrullus L.). Also to encourage experienced farmers to remain in production, there should be policy advocacy on free education and intensification of extension education to farmers. © 2011 Academic Journals. Source

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