Cassava products can be used in livestock feeding. Large quantities
of cassava roots and cassava waste are utilized in the cassava-producing
countries for this purpose.
Let us take a look at some cassava products that are used in feeding
livestock.
1. Chips
This is the most common form in which dried cassava roots are
marketed and most exporting countries produce them. The chips are dried
irregular slices of roots which vary in size but should not exceed 5cm in
length so that they can be stored in silos. They are produced extensively in
Thailand, Malaysia, Indonesia and some parts of Africa.
Processing the cassava chips
The present method of processing chips in Thailand, Malaysia and
some other countries is very simple, consisting of mechanically slicing the
cassava roots and then sun drying the slices. The recovery rate of chips from
roots is about 20 to 40%. However, the products are considered inferior in
quality by some quality-conscious feedstuff manufacturers, although many others
consider them satisfactory.
Preparation of the roots
When the roots are not sorted, peeled and washed, the chips are
usually brown in colour and have a high content of fibre sand and foreign
objects as well as hydrocyanic acid. Trimming, peeling and washing the roots in
a similar manner as for the processing of cassava flour are recommended in
order to produce white chips of superior quality.
Slicing or shredding
The roots are shredded in a special machine, which is usually made
locally. The machine consists of a rotating notched cutting disk or knife
blades mounted on a wooden frame equipped with a hopper. The cassava roots are
cut into thin slices and pieces as they pass through the machine.
Drying
Sun drying is used mostly where the sliced roots are spread out on
drying areas, or concrete floors of various dimensions. Experiments in
Madagascar showed that the concentration of chips during drying should not
exceed 10 to 15kg/m2, the required drying area space being about
250m2 for each ton per day of dried roots produced.
To produce good quality chips the roots must be sliced and dried as
quickly as possible after harvest. The chips should be turned periodically in
the drying period, usually two or three sunny days, until the moisture content
reaches 13 to 15%. The chips are considered dry when they are easily broken but
too hard to be crumbled by hand. The thickness of the slices also has an effect
on the quality of the chips. Thick slices may appear dry on the surface when
their internal moisture content is still high.
When rain threatens during the drying process, the chips are
collected by hand or by a tractor into piles under a small roof. Interrupted
sun-drying affects the quality of the finished chips and pellets. When the
semi-dried chips are wet again by rain, they become soggy and upon completion
of drying lose their firm texture. In rainy regions, where continuous sun
drying is difficult, some form of artificial heat drying is required.
2. Broken roots
Similar to chips in appearance, but generally thicker and longer,
they are often 12 to 15cm long and can jam the mechanism of handling equipment.
They are produced mainly in Africa where local processors prefer to produce
longer roots because of the domestic demand mainly for products suitable for
human consumption, as cassava is part of the staple diet. Once processed into
chips the product becomes inedible, and the producer wants to conserve the
local market.
3. Pellets
The pellets are obtained from dried and broken roots by grinding and
hardening into a cylindrical shape. The cylinders are about 2 to 3cm long and
about 0.4 to 0.8cm in diameter and are uniform in appearance and texture.
The production of pelleted chips has recently been increasing as
they meet a ready demand in the European markets. They have the following
advantages over chips:
- Quality is more uniform;
- They occupy 25 to 30% less
space than chips, thus reducing the cost of transport and storage;
- Handling charges for
loading and unloading are also cheaper;
- They usually reach their
destination sound and undamaged, while a great part of a cargo of sliced
chips is damaged in long-distance shipment because of sweating and
heating.
Pellets are produced by feeding dried chips into the pelleting
machine, after which they are screened and bagged for export. The powdered
chips which fall down during pelleting are re-pressed into pellets and the
process is repeated. There is usually about 2 to 3% loss of weight during the
process.
4. Meal
This product is the powdered residue of the chips and roots after
processing to extract edible starch. It is generally inferior in quality to
chips, pellets and broken roots, has a lower starch content and usually
contains more sand. The use of cassava meal in the European Economic Community
has declined with a shift to the other cassava products during the last few
years. However, there will remain some demand for this product, especially by
small-scale farmers who produce their own feedstuffs. Since it does not require
grinding and thus can be readily mixed with other ingredients.
5. Residual pulp
During the processing of cassava flour, the residual pulp which is
separated from the starch in the screening process is used as an animal feed.
It is usually utilized wet (75 to 80% moisture content) in the neighbourhood of
the processing factory but is sometimes sun dried before it is sold. This
product is considered a by-product of the cassava starch industry and
represents about 10% by weight of the cassava roots.
The approximate analysis of this product (dry matter) is as
follows:
|
Dry matter |
Percentage (%) |
|
Protein |
5.3 |
|
Starch |
56.0 |
|
Fat |
0.1 |
|
Ash |
2.7 |
|
Fibre |
35.9 |
|
Total |
100.0 |
For further info, you can Download the following PDF guide Growing
Cassava now. Feel free to copy and share this with your friends
and family.
- FAO
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