RA 00048.pdf - OAR@ICRISAT

• It converts sorghum as a convenient grain.
• It improves the quality of sorghum products.
• It checks the tendency of shifting from sorghum
to other grains.
• It is an essential step to develop composite
flours and to commercialize sorghum products.
Progress in the areas of sorghum food quality,
although not spectacular, is very impressive. Our
knowledge and understanding of quality criteria of
sorghum food and related grain characteristics are
much better than a decade ago. Rooney and
Murty not only suggested broad guidelines on the
grain quality requirements for different sorghum
foods but also projected the future scope of
coming up with very specific food quality tests
which will be done using a small sample and in
large numbers useful for screening purposes.
They made a very specific comment on why it is
difficult to develop food quality parameters for
sorghum. Sorghum products are exclusively used
for home consumption, unlike rice and wheat, the
products of which are industrialized.
Sorghum food preparation is more skill
oriented. While developing quality parameters it is
very essential to make an extensive study of the
skill oriented traditional methods of sorghum food
preparation and incorporate their significant features
in the standard laboratory recipes.
One of the outstanding contributions of Rooney
and his team is the description of the kernel
structure of sorghum and the possibility of using
endosperm quality as an index of the suitability of
the grain for a particular product. Sorghum breeders
will be delighted to note that all types of
endosperm are suitable for one or the other
product: soft kernel for leavened bread; hard
kernel for rice and porridges; intermediate texture
for rati and tortillas. Sorghums of white or light
yellow color are widely preferred and dark brown
colors are unacceptable. One of the conclusions
made was that except in the case of tortillas, the
color of the product is not very critical, but our
experience in India is different in this respect. One
of the most evident grain characters, as well as
product characters, is color.
The most complicating factor brought out in
their paper is the instability of the food quality
characteristics when tested across localities due
to genotype x processing method interactions.
There is also an indication of probable seasonal
differences. Their data suggest that locational
testing and seasonal testing should be part of the
regional testing program.
However, one of the optimistic notes is in the
variation in the quality of td with pH. It indicates
that slight adjustments in pH may possibly produce
acceptable td within a moderate grain quality
range.
They emphasized the need for assessing the
grain qualities of most acceptable and least
acceptable varieties to determine the acceptable
range in the desirable grain characters. This will be
especially important in screening out the extremely
poor and the least acceptable lines.
They also emphasized the need for developing
status foods for commercial production and evolving
grain varieties suitable for this purpose.
The scope and limitations of improving the
nutritional quality of sorghum are described by
Axtell, Ejeta and Munck in a very pragmatic way.
The paper brought out a number of gaps existing
in our knowledge about the nutritional quality of
sorghum. Several questions were raised about
the ability of sorghum to support the growth of
children and also its desirability as human food.
One of the major issues discussed by them was
tannin in sorghums, and the interaction between
tannin content and protein quality.
In the International Symposium on Sorghum
Grain Quality, Butler gave an account of tannins
and made one interesting comment that because
of their high affinity for prolamine, the biologically
available protein in the high-tannin varieties is of
better quality and probably this is nature's way to
protect sorghum eaters.
Axtell. however, suggested that two alternatives
for detoxicating tannins are alkali treatment
and denuding. A better understanding of the
biochemistry of sorghum tannins and their interaction
with seed protein needs major emphasis in
the eighties.
Axtell also described the present status of the
high-lysine breeding program and the future prospects.
The situation seems to be quite encouraging.
He mentioned that in Ethiopia, the homeland
of the high-protein and high-lysine varieties, the
heads are roasted in the late dough stage and the
grain is eaten in a mixture with normal varieties
because the high lysine grains have a superior
flavor.
He also discussed the problems confronting the
development of suitable high-lysine varieties. The
dented grain (lines with a high-lysine content) and
low yield of the Ethiopian lines are the critical
characters for the low acceptability by the farmer.
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