Physicochemical compositions, nutritional and functional properties, and color qualities of sorghum-orange-fleshed sweet potato composite flour

Mary Damilola Jenfa; Oluwasola Abayomi Adelusi; Aderonke Aderinoye; Oluwafemi Jeremiah Coker; Itohan Ebunoluwa Martins; Olusegun Adewale Obadina

doi:10.1002/fsn3.3922

Physicochemical compositions, nutritional and functional properties, and color qualities of sorghum-orange-fleshed sweet potato composite flour

Food Sci Nutr. 2024 Jan 28;12(4):2364-2378. doi: 10.1002/fsn3.3922. eCollection 2024 Apr.

Authors

Mary Damilola Jenfa¹, Oluwasola Abayomi Adelusi², Aderonke Aderinoye³, Oluwafemi Jeremiah Coker⁴, Itohan Ebunoluwa Martins¹, Olusegun Adewale Obadina^{1

2}

Affiliations

¹ Department of Food Science and Technology Federal University of Agriculture Abeokuta Nigeria.
² Department of Biotechnology and Food Technology, Faculty of Science University of Johannesburg Doornfontein South Africa.
³ AgriHub Lagos Nigeria.
⁴ Department of Food and Bioproduct Sciences University of Saskatchewan Saskatoon Saskatchewan Canada.

Abstract

Sorghum and orange-fleshed sweet potato (OFSP) flours were blended to produce composite flours at eight different ratios of 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, and 20:80, respectively, whereas 100% sorghumflour was used as control. The physicochemical compositions, nutritional and functional properties, as well as color attributes of the composite flour blends were evaluated. The acquired data were analyzed using ANOVA, and the means were separated using the Duncan multiple range test. Significant differences (p < .05) were observed in the physicochemical and nutritional properties of the flour blends. The protein levels in the composite flour decreased as the proportion of OFSP flour increased. However, the levels of vitamins, particularly vitamins A and C contents of the composite flours increased with higher proportions of OFSP, ranging from 0.27 and 1.74 mg/100 g in sample S₁₀₀ to 2.13 and 2.12 mg/100 g in sample S₂₀O₈₀, respectively. In contrast, an increase in the percentage of OFSP flour resulted in a decrease in the contents of vitamin B-complex, particularly vitamins B₂ and B₆. These values decreased slightly from 0.19 and 1.98 mg/100 g in sample S₁₀₀ to 0.16 and 0.03 mg/100 g in sample S₂₀O₈₀, respectively. Furthermore, as the proportion of OFSP flour increased, there was a reduction in the calcium levels from 17.39 mg/100 g in the 100% sorghum sample to 13.52 mg/100 g in the S₂₀O₈₀ sample. However, no particular trend was observed in, magnesium, iron, and phosphorus levels. Sample S₅₀O₅₀ had the highest percentage of essential and conditional amino acids, except for cysteine, valine, and phenylalanine. The findings also revealed significant variations (p < .05) in the composite flour samples' functional properties and color measurements. Substituting sorghum with OFSP in sorghum-based food products would significantly increase their vitamin A content.

Keywords: composite flour; nutritional properties; physicochemical compositions; sorghum; sweet potato.