Optimization of malting conditions of Pearl millet [Pennisetum glaucum (L.)R.Br.] using Box-Behnken design

361-365In the present study, malting conditions of Pearl millet [Pennisetum glaucum (L.)R.Br.] were optimized using Box-Behnken design. The three variables chosen were gibberlic acid (X₁), temperature (X₂) of malting and days of germination (X₃) for optimal yield of ⍺-amylases and proteases in the malt. A total of 15 runs by combination of each factor were carried out and contribution of each factor was established. The t-values and p-values obtained revealed that all the three variables significantly contribute to the formation of both enzymes during malting. Optimal conditions required for the formation of maximal expression of ⍺-amylases (323.03 units/g of malt) as provided by the model are as follows: gibberlic acid 1.053 ppm, temperature to be maintained at 32.98oC and the malt must be obtained at the end of 3.68 d. The set of conditions maintained to get an optimal protease yield (32.968 units/g of malt) are: gibberlic acid, 1.0743 ppm; temperature, 33ºC; and the malt must be obtained at the end of 3.4 d (78 h). Following these conditions, malt with α-amylase and protease activities of 320 units and 31.24 units per g, respectively were obtained