Impact of Tuber Section, Steeping Solution, and Concentration on Physicochemical Properties of Yam (Dioscorea rotundata) Flour

This study examined various factors such as tuber cutting (TC), tuber processing method and tuber processing duration (TPM and TPD), soaking solution type and soaking solution concentration (SST and SSC), as well as parameter analytical temperature (PAT) on flour samples prepared from different parts of yam tubers. Proximate composition analysis showed significant differences (p < 0.05) in carbohydrate, protein, fat, ash, fiber, and moisture content. In particular, the middle part had the highest protein content (5.49 ± 0.71%), while the main part had the highest carbohydrate content (72.62 ± 2.83%). Physicochemical properties varied significantly (p < 0.05) between treatment methods, including pH, gel and boiling points, total soluble solids, swelling index, and water absorption. TPM significantly affected pH, and boiled yam flour had the highest pH (8.01 ± 0.76). TPD also affected properties such as gel point temperature, with longer holding times decreasing the temperature. SST and SSC had significant effects on pH, gel point temperature, and total soluble solids. Yam flour soaked with sodium carbonate had the highest pH (12.02 ± 0.87), while increasing the concentration of the soaking solution resulted in higher pH values. PAT significantly affected pH and water absorption capacity, with higher temperatures leading to higher values.

Keywords: Yam, Physicochemical, Flour, Tuber Sections, Steeping Solution.