Colour Profile, Pasting and Sensory Properties of Processed Sweet Potato Flour
O. I. Ajayi *
Department of Biotechnology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
S. B. Kosoko
Department of Food Technology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
B. J. Awogbemi
Department of Production Analytical Services and Laboratory Management, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
T. A. Okedina
Department of Biotechnology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
C. P. Onyemali
Department of Biotechnology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
J. Ehiwuogu-Onyibe
Department of Biotechnology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
A. K. Lawal
Department of Biotechnology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
G. N. Elemo
Department of Food Technology, Federal Institute of Industrial Research, Oshodi, P.M.B. 21023, Ikeja, Lagos State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
In this study, sweet potato was purchased and processed using different methods to obtain 4 different sweet potato flour samples. Sample A was unfermented sweet potato flour, sample B was fermented spontaneously, while sample C and D were produced by fermentation using indigenous starter cultures of lactic acid bacteria and yeast for 48 h and 72 h respectively. Colour profile, Pasting and Sensory evaluation was conducted. The whiteness (L* value) obtained in this study is within the range of value (87.29-89.52), Also, the redness value (a*) and yellowness value (b*) of the sweet potato flour samples also showed a significant difference (p<0.05). Sample a had a higher value when compared with samples B,C and D. Pasting properties such as peak viscosity, trough viscosity, breakdown viscosity, setback, pasting temperature were determined. It was noticed that fermentation process and increase in fermentation time significantly (p<0.05) decrease the peak viscosity in this research work and all samples had a higher cooled paste viscosity than their corresponding hot paste viscosity. Nevertheless, sensory evaluation was carried out using thet 9-point hedonic scale, samples A,B,C,D are significantly different (P < 0.05).
Keywords: Starter culture, sweet potato flour, pasting properties, colour profile, sensory evaluation