Abstract

Solid state fermentation was employed to isolate the starch from finger millet to improve its functional properties. This process was optimized by Box-Behnken response surface methodology by varying pH (4-7), innoculum concentration (10 -30), temperature (25-35oC) and time (2-6 d). Aspergillus oryzae (MTCC 3107) was obtained from National hemical Laboratory, Pune and used for this study. Growth medium of 0.2% of KH2PO4, MgSO47H2O and soluble starch each along with traces of FeSO4.7H2O in 100 ml distilled water was used. Higher starch (0.64 mg/g) was isolated at pH 5.65, innoculum concentration of 28.57 per cent and temperature 35oC, time 3.8 days. A quadratic equation was fitted to develop a relationship between independent and dependant variables. The fitted model has high regression coefficient (R2 - 0.99), adjusted regression coefficient (Adj.R2 -0.99) with less standard deviation (SD- 0.005). This study concluded that SSF could be an effective method for isolation of starch from finger millet.

Keywords: Starch isolation, Finger millet, Solid state fermentation, RSM, Modeling