RA 00048.pdf - OAR@ICRISAT

Industrial Milling of Sorghum for the 1980s
L. M u n c k * , K. E. Bach Knudsen*, and J. D. A x t e l l * *
If sorghum growing semi-arid countries are to be
self-sufficient in cereals for food during the 1980s,
industrial milling and marketing of sorghum food
products have to be introduced as quickly as
possible. However, endeavors to supply rapidly
growing cities with locally grown sorghum come
up against several severe obstacles.
First, in these countries sorghum is a crop for
the subsistence farmer. There is very little sorghum
on the market, in part because of distorted
governmental food price policies. In many countries,
imported cereals are subsidized and sold at a
lower price than sorghum. In Tanzania, for example,
a white maize product is currently sold at one
third of that of grey whole milled sorghum flour,
even though maize gives a good yield in only 2 out
of 5 years.
Second, the milling process devised for sorghum
has been based on traditional wheat and
maize technologies. Therefore, highly acceptable
white maize and wheat products rapidly gained a
foothold on the urban markets, leaving sorghum
as a low prestige food crop associated with the
backwardness of rural areas. Thus even in countries
where sorghum as a food has age-old
traditions, it is nowadays regarded as a feed crop.
However, in the rural areas, locally developed
techniques such as hand pounding for decortication
are still in use and produce highly acceptable
products. In these areas soghum is preferred to
maize. Unfortunately these local techniques are
now rapidly disappearing, and it is therefore
important to have them documented before it is
too late.
* Carlsberg Research Laboratory, Department of
Biotechnology, Gamle Carlsbergvej 10, DK-2500
Copenhagen-Valby, Denmark.
** Department of Agronomy, Purdue University, West
Lafayette, Indiana, USA.
Determination of Needs Through
Studies of Local Practices
Studying local practices is a prerequisite for a
precise evaluation of the acceptability and nutrition
of sorghum, and its role in a mixed food diet.
Such knowledge will contribute to an adequate
background for the future development of industrial
processes. Plate 1 : c displays selected flour
samples which are representative of the current
situation in Tanzania (Eggum et al. 1982) regarding
sorghum milling. It is seen that the hand-pounded,
high-yielding variety 2Kx17/B/1 (comparable with
Lulu D) is by far the most acceptable sample in
terms of whiteness. The machine milled Lulu D
sample, processed in a local village mill devised
for rice, comes next in quality, while the commercial
Lulu D flour is almost as dark as whole milled
sorghum. In Tanzania the latter product is three
times as expensive as maize flour. It goes without
saying that the quantities of sorghum flour sold
under these circumstances are extremely small.
However, the yield-improved, short sorghum
varieties of the Lulu D type (Lulu, 2Kx17/B/1.
2Kx89 in Figure 1) are not ideal for hand pounding
(Eggum et al. 1982). It is seen from the cross
sections of seeds in Figure 1 that they are much
softer than the local Tanzanian hard varieties
(T300, T236, T261, T295, and T275), which are
preferred for hand pounding in the rural areas. If a
fine flour of comparable whiteness is desired,
the modern white varieties yield only about 50%,
while yields from local types range from 73 to
83%. Furthermore it is seen in Table 1 that, using
hand decortication, yields of nutrients (starch 61 %
and protein 44%) are very low in the modern
varieties exemplified by Lulu D. Comparable
figures for the local varieties are 9 2 % starch and
75% protein. It is therefore clear that presently
introduced sorghums are unsuited for hand
pounding. When decorticated to a yield of 80%,
International Crops Research Institute for the Semi-Arid Tropics. 1982. Sorghum in the Eighties: Proceedings of
Symposium on Sorghum, 2-7 Nov 81, Patancheru, A.P.. India. Patancheru, A.P. India: ICRISAT.
the International
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