Utilization Of Cassava Research Articles

THE EFFECT OF PROCESSING ON THE NUTRIENT CONTENT OF CASSAVA (MANIHOT ESCULENTA CRANTZ) LEAVES

Leaves of two varieties of cassava (Manihot esculenta Crantz) – TME1 (local) and TMS30572 (improved) – were subjected to African household processing (heat-treated, pounded and cooked and crushed, ground and cooked) and compared for proximate composition, minerals, vitamins and antinutritional factors. The processing methods had no effect on ash, lipids, protein, fiber, total carbohydrate, carotene, calcium, magnesium, potassium, sodium, phosphorus, copper, zinc and manganese but produced diminution in free sugars (23.2% reduction), ascorbic acid (77.7% reduction), thiamine (37.1% reduction), cyanogenic potential (>99% reduction) and tannin (55.2% reduction;) levels. On the contrary, iron level increased three- to fivefold with grinding but not with the pounding process. This study showed that adequate processing practically detoxifies cassava leaves with considerable nutrient retention, thus enhancing utilization of cassava leaves for human consumption. PRACTICAL APPLICATIONS This study has clearly shown that cassava leaves are very nutritious. However, they also have anti-nutrients which can render them toxic. This is responsible for the fear exhibited in the consumption of cassava leaves because of anticipated poisoning. This study shows that African processing methods tremendously reduce the ant-nutrients with minimal loss in the nutrients. There should therefore be no fear in the utilization of cassava leaves either for animal feed formulation or man's own direct consumption as a good source of leafy vegetables. The food quality of processed cassava leaves renders them a potential source of raw material for the animal feed industry as well as for the formulation of weaning foods especially for the underdeveloped world.

Farmers’ perceptions of practices and constraints in cassava ( Manihot esculenta Crantz ) chips production in rural Cameroon

A survey aimed at collecting information on practices and constraints in the production of cassava (Manihot esculenta Crantz) chips, a transformed cassava product obtained through fermentation and drying of its fresh roots was carried out in 45 villages located in three geographical regions (Yaounde, Mbalmayo, and Ebolowa) of the humid forest zone of Cameroon. A structured questionnaire to interview farmers was employed. Out of 225 farmers sampled, 212 (94%) relying on chips as food and source of income were women. Overall, 51% of all farmers marketed chips locally. Three distinct forms of chips such as broken pulp (62%), balls (25%), and pellets (13%) were cited as being locally produced by farmers. These were obtained either through air fermentation (cassava pellets), or submerged fermentation (broken pulps and balls), using starters or fermenting agents (31% of responses) or without using them (69%). Chips were mainly home-stored in jute and or/plastic bags (43% of responses), open or closed containers (36%), or on devices hanging over the fireplace (21% of responses) for as long as 180 days. Dark spots or discolouration occurring as a result of chips damage were reported by the majority of respondents (82%) as frequent on cassava chips. These were related to insufficient drying (42%), the use of infected cassava roots by plant pathogenic microbes from the fields (12%), or too long drying of chips under sun light (11% of responses). To avoid dark spots and/or discolouration, 112 farmers out of a total of 185 who were aware about chips damage, practiced sundrying, and 21% of this total dried their chips over the fireplace to control chips damage. Pests and diseases problems (47% of responses), mainly related to the incidence of Stictococcus vayssierei Richard (Homoptera: Stictococcidae) and lack of market (26%) were cited by farmers as the most important constraints in cassava chips production. From the results obtained, this study outlined that the potential utilization of cassava and its derived products for industrial purposes is not yet exploited in the locations investigated. Additionally, the study also raised concerns about the safety and hygiene associated with traditionally processed and stored cassava chips in the investigated areas.

Utilization Of Cassava and Pawpaw Diets By Growing Snails

Two hundred and twenty five (225) growing snails of an average weight of 70g were used for the feeding trial, with five dietary treatments. The trial lasted fourteen weeks. The diets were isonitrogenous (18.30% crude protein) and Isocaloric (2500kcal/kg M. E). The treatments were T1, T2, T3, T4 and T5. The rations had 10% inclusion of pawpaw leaf (T2) Unripe Pawpaw fruit (T3), Cassava peel (T4) cassava leaf (T5). The treatment without the inclusion of pawpaw and cassava meal served as the control treatment (T1). Snails in (T2), had the best performance in terms of daily weight gain (3.65g), efficiency of feed utilization (0.49) and feed to gain ratio (2.02), closely followed by T4 (ration with 10% cassava peel meal); T5, T3 and T1 (control treatment). Feed intake in all the treatments was not depressed. Feed intake was generously enhanced in T4 and T5, revealing that the inclusion of cassava peel and leaf enhanced feed intake. The high feed intake in T4 and T5 affected the feed to gain ratio and efficiency of feed utilization. Feed to gain ratio values of 4.18, 2.02, 1.85, 6.13 and 6.29 for (T1, T2, T3, T4 and T5) showed that T2 and T3 were the best, this also reflected in the efficiency of feed utilization, which showed that T2 and T T3 were the most efficient. It could be concluded that the inclusion of parts of cassava and pawpaw in the rations of growing snails, had positive impact on the growth and performance indices. In terms of rating, pawpaw leaf and cassava peel inclusion were ahead of pawpaw fruit and cassava leaf. All the plant parts were valuable, because all the treatments were better than the control. Snail farmers are encouraged to adopt the utilization of pawpaw and cassava parts in snail feeding, because of their availability and affordability. Key words: Cassava, pawpaw, growing snails Journal of Agriculture, Forestry and the Social Sciences Vol.2(2) 2004: 84-88

The effect of supplementation with ficus leaves on the utilization of cassava peels by sheep

The objectives of this experiment were to determine the effects of dried Ficus exasperata leaves supplementation on voluntary feed intake, digestibility of nutrients and liveweight gain of sheep given ad libitum access to dried cassava peels. A total of 48 Djallonké wethers and ewe lambs (avg. wt 13.5 kg ± 1.2 kg), housed individually and given ad libitum access to dried cassava peels were randomly allocated to one of six dietary treatments comprising 0, 50, 100, 150, 200 and 250 g d −1 of dried F. exasperata leaves. Supplementation increased ( P < 0.05) daily dry matter (DM) intake from 44.0 g kg −1 LW 0.75 for animals that received no supplement to 81.2 g kg −1 LW 0.75 for animals that received 250 g d −1 of supplement. Digestibility coefficients of DM, organic matter and acid detergent fibre in the diets were depressed ( P < 0.05) as a result of supplementation. However, intake of the basal diet increased ( P < 0.05) from 44.0 g kg −1 LW 0.75 d −1 for control animals, to 55.1 g kg −1 LW 0.75 d −1 for animals that received 200 g d −1 of supplement. Animals which received 250 g d −1 of leaves had the fastest growth rates (53.6 g d −1) followed by those that received 200 and 150 g d −1 ( P < 0.05). Although the supplement was less digestible than the basal feed, it promoted a higher DM intake and growth rate, presumably due to the supply of nitrogen and other nutrients.

Utilization of cassava peels as substrate for crude protein formation

Mash prepared from cassava peels was inoculated with either Sacchromyces cerevisiae or Candida tropicalis and then left to ferment for 7 days. Chemical analysis of the fermented mash showed substantial increase in crude protein content and decrease in carbohydrate content of the mash. The results also revealed slight increases in the ash, fibre and lipid content of the fermented mash. It was further observed that, when the mash was supplemented with inorganic nitrogen sources (urea, ammonium sulfate or sodium nitrate) before commencement of fermentation, the amount of crude protein formed was almost doubled. This enhanced crude protein production was highest in the mash supplemented with urea. Temperature of 30 degrees C, pH of 5.5 and moisture concentration of 130% were found to be optimum for crude protein formation by the organisms growing on the mash.