Physicochemical Properties of Sorghum Biscuits Enriched with Defatted Soy Flour

Aims: To evaluate the physicochemical properties of sorghum biscuits enriched with defatted soy flour, at specified ratios.
Study Design: Two - way ANOVA
Place and Duration of Study: Department of Food Science and Technology, Federal University of Technology, Akure, Nigeria, from January to September, 2012.
Methodology: The sorghum whole grain used was milled into flour (S) to pass a 500 µm sieve. The defatted soy flour (D) was supplied by Jof – Ideal Industry, Owo, Nigeria. Sorghum flour was blended with defatted soy flour (SD) at the following ratio – SD1 (70.00:30.00), SD2 (77.50:22.50), SD3 (85.00:15.00), SD4 (87.50:12.50), SD5 (90.00:10.00), SD6 (95.00:5.00), and SD7 (92.50:7.50) and blends were used for biscuits production. The following analysis were carried out on the biscuit samples namely - proximate composition, mineral composition, physical characteristics and colour.
Results: Significant differences (P≤0.05) were observed in the proximate, energy and mineral compositions of the biscuits. The protein content ranged from 7.3 ± 0.2 to 11.2± 0.2%; crude fat ranged from 12.0± 0.2 to 18.1± 0.1%; crude fiber content ranged from 2.0 ± 0.0 to 3.8 ± 0.0% while the carbohydrate content ranged from 58.2± 0.2 to 70.6 ± 0.1%. Results obtained compare favourably with the recommended dietary intake for each nutrient. The calculated energy value ranged from 1825.8 to 2026.1 Kj/100g. The Na:K ranged from 1.0 to 1.5 while the Zn:Cu ranged from 1.2 to 3.0. The diameter of the biscuits ranged from 4.50 ± 0.14 to 5.80 ± 0.14cm; Weight ranged from 8.27 ± 0.03 to 8.90 ± 0.14g; thickness ranged from 0.62 ± 0.01 to 0.84 ± 0.06cm. Breaking strength ranged from 1.4 to 2.7N. No significant differences were observed in the L*, a* and b* values of the biscuits.
Conclusion: Sorghum biscuits enriched with defatted soy flour met recommended dietary intake for each nutrient. Hence, formulated biscuit could therefore be a useful tool in reducing protein-energy malnutrition.