Chemical, structural, and techno-functional characterization of yam (Dioscorea) flour from South West Ethiopia
Sosina Gebremichael Argaw,
Tewodros Mulualem Beyene,
Henock Woldemichael Woldemariam,
Tarekegn Berhanu Esho,
Shiferaw Ayalneh Worku,
Hiwet Meresa Gebremeskel,
Kebede Nigussie Mekonnen
Affiliations
Sosina Gebremichael Argaw
Department of Industrial Chemistry, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Centre of Excellence for Biotechnology and Bioprocess, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia
Tewodros Mulualem Beyene
Jimma Agricultural Research Centre, Jimma, P.O. Box 192, Ethiopia
Henock Woldemichael Woldemariam
Department of Chemical Engineering, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Centre of Excellence for Biotechnology and Bioprocess, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia
Tarekegn Berhanu Esho
Department of Industrial Chemistry, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Centre of Excellence for Biotechnology and Bioprocess, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia
Shiferaw Ayalneh Worku
Department of Chemical Engineering, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Centre of Excellence for Biotechnology and Bioprocess, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia
Hiwet Meresa Gebremeskel
Department of Chemical Engineering, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Centre of Excellence for Biotechnology and Bioprocess, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia
Kebede Nigussie Mekonnen
Department of Industrial Chemistry, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Nanotechnology Centre of Excellence, Addis Ababa Science and Technology University, Addis Ababa, P.O. Box 16417, Ethiopia; Corresponding author.
Yam (Dioscorea spp.) is a versatile tuber crop that holds nutritional, cultural, and economic values. Yam is a major source of carbohydrates for tropical Countries and provides various nutrients and health benefits. This study aims to characterize the chemical, structural, and thermal properties of yam flour using various analytical techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermal analysis. Additionally, the pasting and rheological properties of yam flour were evaluated, as they are crucial for product development and enhancing the value of this unconventional vegetable. D. cayenensis complex had the highest total starch (64.63 ± 1.61 %) and soluble sugar (4.95 ± 0.46 %) content, which was significantly higher than other yam species. The amylose content of yam flours showed significant (p < 0.05) differences among the yam species. D. cayenensis flour exhibited significantly the highest peak (2923.66 cP) and steak back viscosity (2097.66 cP) among the yam species associated with their greater amylose content. There were notable variations in pasting and gelatinization parameters among the species. The peak temperatures of D. bulbifera and D. cayenensis complex were significantly (p < 0.05) higher than D. cayenensis and D. rotundata flours. The rheological measurements of yam flours demonstrated solid-like behavior with varying intensities. Furthermore, the morphology of tuber yam flour particles was oval to ellipsoidal shaped, with some appearing ovoid, and the smaller granules appearing spherical. The X-ray diffraction showed that all yam flours exhibit a B-type pattern. This study provide a better understanding of this unconventional vegetable's potential applications in the food industry and contribute to its value addition.
