Optimization of germination conditions of blue corn (Zea mays L.) by Taguchi orthogonal array methodology

A Taguchi L₉ orthogonal array methodology was used to optimize the conditions for maximal germination percentage in blue corn grains. The factors studied included steeping time, ratio of steeping water to corn grain, germination temperature and time. The optimal conditions included a steeping time of 24 h, an amount of 100 g of grain steeped in 200 mL of water and a germination time of 96 h at 25°C for a predicted germination of 90.6%. Under these conditions, 94% of the grains germinated reaching a moisture content of 43%. An increase in the range of 154 to 160% for total phenolics and 43% for anthocyanrns was obtained after 96 h of germination. The 1,1-diphenyl-2- picrylhydrazyl radical (DPPH) antioxidant activity increased slightly during the germination process. In conclusion, the process of germination was beneficial due to the increase in antioxidant compounds in the blue corn grain.