Determination of Some Physicochemical Properties of Guinea Corn (Sorghum vulgare)

Abstract

In this study, some physical and chemical properties of two cultivated varieties
of guinea corn (brown and white) were studied. The physical properties are pericarp,
colour, kernel size, 1000-kernel weight and moisture content. Standard laboratory
procedures by Association of Official Analytical Chemists (AOAC) were followed to
obtain chemical compositions such as oil, crude fibre, ash and protein from the two
varieties of guinea corn. The results show that brown variety contains 5.03 % oil, 2.33 %
crude fibre, 1.87 % ash and 10.80 % protein; while the white variety contains 3.03 % oil,
1.97 % crude fibre, 1.99 % ash and 10.00 % protein. Nitrogen free extracts were found to
be 1.66 % and 73.97 % for brown and white samples, respectively. The amylose contents
were 35.00% for brown and 21.67 % for white. Mineral contents such as calcium,
potassium and phosphorus determined showed that the brown variety contains 0.14 %
calcium, 0.19 % potassium and 0.16 % phosphorus while the white variety contains 0.27 %
calcium, 0.21 % potassium and 0.12% phosphorus. The carbohydrate and energy values
were obtained to be 72.12 % and 374.07 kcal/100g for brown and 73.98 % and 363.10
kcal/100g for white. From the results, even though the carbohydrate and energy values of
guinea corn compare favourably well with those of other cereals, the mineral contents were
lower than the previously reported values for cereals generally. Thus, in formulating animal
feed or for human consumption it is recommended to mix the two varieties of guinea corn
with protein rich foodstuff such as wheat or soyabean, so as to obtain the optimum dietary
requirement needed by the body