Cassava foliage: Chemical composition, cyanide content and effect of drying on cyanide elimination

Abstract

The chemical composition and cyanide concentration in the foliage of four cassava cultivars (M Col 113, M Col 22, M Col 1684, CM 342-170) were evaluated at four plant ages (6, 8, 10 and 12 months). The effect on cyanide elimination of sun-drying on a concrete floor and of oven-drying at 60°C was also studied, including some observations on the tannin content of dried foliage. The proximal composition, calcium and phosphorus contents, as well as the amino acid composition of dried cassava foliage compared favourably to that of sun-cured lucerne meal. In most cases, foliage from 6-to 12-month-old plants contained 25 to 30% dry matter, and as dried foliage had 13 to 20% crude protein and 16 to 20% crude fibre. Crude protein and crude fibre were the two chemical constituents which varied the most with plant age. The average gross energy of dried cassava foliage was 4.12 kcal kg-' with a range of 3.90 to 4.35 kcal kg-'. Sun-drying eliminated more cyanide than oven-drying (82 to 94% vs 68 to 7696, respectively) and in addition, most of the cyanide in sun-dried foliage was free cyanide (62 to 77%) whereas only 24 to 36% was found as such in oven-dried foliage. Sun-dried foliage samples had consistently lower tannin content than the corresponding oven-dried samples.

Antinutrients in the cassava (Manihot esculenta Crantz) leaf powder at three ages of the plant

“…Table 2 shows the polyphenol contents, trypsin inhibitor, saponin and the hemagglutinative activity of CLM from these five cultivars at TAP. In general, it is observed that the polyphenol contents increased with the maturity of the plant, and this tendency was already described 21 .…”

“…This wide variation is probably due to the genetic differences among the cultivars, the plant ages, the leaf drying temperatures, the leaf maturity, the soil fertility and the pluviometric precipitation index. The influence of the lack of rainfall events on the reduction of cyanide contents is reported 11,21 . For this reason, the data of the pluviometric precipitation were collected from the planting period (October/2000) until the last collection of the leaves (March/2002), and are shown in Figure 1.…”

“…The cyanide is the main toxic factor restricting the use of CLM, which presents a wide variation range from 5.3 to 80 mg.100 g -1 dry matter (DM) 3,6,21,37,39 . Few data related to the influence of the plant age on the contents of the CLM antinutrients are registered in the available literature.…”

Nutrients in the cassava (Manihot esculenta Crantz) leaf meal at three ages of the plant

“…When comparing the contents of magnesium and calcium in CLM (g/100 g DM) with data reported in the available literature, that is, 0.26 to 0.97 for magnesium [9,16,20,23] and 0.04 to 1.63 for calcium [1,6,15,16,23,9], lower magnesium and similar calcium contents were observed, except for the Ouro do Vale cv. ones with higher levels for calcium at all TAP.…”

Effect of Pellet Containing Cassava Leaves Meal at Various Particle Size on Broiler

“…Cassava leaves were used in the study came from various varieties aged 8-10 months was taken from the experiment station of State Polytechnic of Lampung. Cassava leaves treated with a combination of chopping 2-3 cm, wilting 24 hours at room temperature, and drying it under the sun for 2 days (Gomez and Valdivieso, 1985). Milling cassava leaves and other feed ingredients in the form of grain using semi-fixed a hammer mill machine with a screen 2, 3, and 5 mm, while the feed material in the form of mash not grinded.…”