South Africa has a
diversity of cultures with their traditional foods. These cultures have for
several years prepared and enjoyed traditional dishes which have kept them well
nourished (Khumalo, 2004). Those were times when rural communities were still
owning vast areas of land and large herds of cattle. Immigration and the
introduction of western and eastern dishes have caused the traditional foods to
Research Council and genebank of the National Department of Agriculture has recorded
a very limited collections of wild vegetables such as Corchorus Olitorius from
the whole country and there is no single genetic material on wild vegetables
from northern Kwazulu-Natal held in the national genebank. There is equally no
information on processing and chemical evaluation of species. (F.B Lewu et
Beside the fact that
edible indigenous plant have been used as food for years (Vorster et al. 2008;
Adebooye and Opabode 2004), some recent publication indicated that the use of wild
vegetables in South Africa is in decline (Steyn et al. 2001; Modi et al.,
(Flyman and Afolayan,
2006b) have suggested that the lack of knowledge about nutritional composition,
cooking methods and ways of preservation are considered as reasons for low use
of wild vegetables in the Southern Africa.
(A.T Modi et al., 2013)
described amadumbe Colocasia esculenta
(L.)Schott as a neglected and underutilised crop in sub-Saharan Africa due
to insufficient agronomic informations on it.
Current literature does
not provide enough informations on amadumbe (Colocasia Esculenta) in many aspects such as physiology, production
in South Africa and processing by drying.
However, this study
will focus on exploring some information available on Amadumbe as well as its
drying behaviour under several drying temperatures in an industrial tray dryer.
Thus, the major points
which will be discussed in this this review are: Amadumbe
overview,drying,drying mechanism of tuber, drying curves, drying systems,evaluation:product
and dryer,determination of energy required to dry amadumbe, Mathematical
modelling of the drying characteristics of amadumbe .
esculenta), also called taro, is bred for its edible corms in subtropical
and tropical regions of the world. Rich in carbohydrates and energy, it is one
of the staple foods in the developing countries of Africa, the West Indies and
Asia (Liu, Donner, Yin, Huang, & Fan, 2006).In South Africa, amadumbe is considered
as traditional crop cultivated by rural
farmers in KwaZulu-Natal for subsistence. Beside the cultivated one, amadumbe
also grows in the wild. Cultivated amadumbe (Colocasia esculenta varesculenta) is grown on dry land and consists
of poorly developed stolons. However, wild amad-umbe (Colocasia esculenta var. stolonifera) is adapted to wet land and
possesses well-developed stolons.
Fig.1Amadumbe corms from cultivated and wild sources.
A: cultivated: Colocasia esculenta var esculenta, B:
wild: Colocasia esculenta var stolonifera.
According to (Chay-Prove and Goebel, 2004), the
amadumbe leaves are generally not eaten, but some traditional communities do
use them like any green vegetable. The starchy corm is the one most eaten by
people and also marketed by countries like Australia, New Guinea, Sunda Island
and South Africa. Amadumbe do not have stems but have long petioles, which are
also rich in nutrients. Nutritional information of amadumbe appears in table
1.1, and shows comparison of major nutrients.
Table 1.1 Amadumbe Nutritive values
(Langenhoven et al., 1991)
Per 100g edible
Edible portion (%)
ascorbic acid (vit
Table 1.1 displays major nutrients contained in
different parts of the plant. It appears that the corm has the highest
percentage of energy which is 257 kilojoules, with 19g carbohydrates and 0.18mg
major nutrients are higher in the leaves than any other part of the crop, while
petioles are only high in moisture, fibre and edible portion. Taro can be used
as a substitute to cereals and consumed by children sensitive to milk (Lee,