3.4. Optimisation and model validation
The analysis of the model showed that the optimal parameters
required to obtain the highest alcoholic degree (17.94%, v/v) were:
BT = 100.14 C, MC = 43%, and AC = 1.45‰. The maximum alcoholic
degree obtained experimentally was 18.3% (Fig. 3), which was very
close to the predicted value. Previous researchers have also used
the response surface methodology (RSM) to optimise different processes
(Fan et al., 2012; Zhang et al., 2012). For example, Yu,
Ramaswamy, and Boye (2012) used RSM to investigate the effects
of the feed moisture, screw speed, and BT on the physical properties
of extruded corn flour and soy protein isolate. Their results
showed that the well the experimental data. Furthermore, the optimised
alcoholic degree obtained in this study was similar to a previous
investigation, where Gohel and Duan (2012a) used Indian
broken rice to produce ethanol and the maximum alcoholic degree
was 16% (v/v at 20 C)