Variability of properties of starch isolated from yam-soybean composite flour formulation intended for ‘amala’ (yam-based doughmeal) preparation

نویسندگان

1 Department of Food Science & Technology, Federal University of Technology, Akure, Nigeria

2 Department of Food Science & Technology, Federal University of Technology, Akure, Nigeria

doi
10.22059/jfabe.2023.363895.1149
چکیده

This study investigated variability in starch properties within a yam-soybean flour blend intended for making Amala. Soybean flour was added at 10-50% levels. Starch was isolated using standard procedures and evaluated for yield, pH, bulk density, swelling power, water and oil absorption, pasting properties, and Fourier Transform Infrared spectroscopy. The result showed that substituting yam flour with soy flour caused significant yield changes in isolated starch from the blends. Higher soybean flour concentration in the composite formulation resulted in decreased starch yield. The pH values also moved towards more acidity with an increase in soybean flour level. The bulk density (0.61 – 0.79 g/cm3), WAC (246.98 – 265.76%), OAC (120.4 – 181.17%) of the isolated starch samples were all found to decrease as a result of soybean flour inclusion. However, the swelling capacity of the isolated starch samples (2.90 – 3.69 g/g) was found to increase with soybean flour inclusion. The pasting properties of the isolated starch samples including peak viscosity (2745 – 5743 cP), breakdown viscosity (318 – 1006 cP), final viscosity (3845 – 8120 cP), and setback viscosity (1178 – 3434 cP) were all found to decrease with the inclusion of soybean flour; while peak time (5.27 – 5.32 min) and peak temperature (82.4 – 85.1 ) increased in values as a result of soybean flour inclusion. The FTIR spectroscopy of the starch samples exhibited differences in the spectra pattern in terms of shifting in the position of the wavenumber and the appearance of new functional groups.